Get Your Science On!

Fermentation: Break it DOWN

2009-08-20T07:21:00.000-07:00

Beer!
I love beer! I love beer so much I am on a committee for beer. But how many of you out there know about the chemistry behind making beer? I mean the itty-bitty, teeny-weenie changes that take place on a molecular level. To know about fermentation, you need to know something about oxidation and reduction. To know about oxidation and reduction, you have to know how electrons move between reducers and oxidizers. It’s like a Russian Doll, you see. One thing fits inside a smaller one, then a smaller one, then smaller, until you get down to the teeeeeeny tiny world of the electron. Really, fermentation (thus beer brewing) is about how electrons move around.

Think of oxidation/reduction this way: You’re at a cocktail party. You’re having a good time, drinkin’ drinks, chatty chatty when THAT couple walks in. You all know the couple I’m talking about. The couple who live to shuffle their emotional baggage between one other. Collective sigh. Don’t make eye contact. Uh oh. Here they come to talk to you. For the purposes of this analogy, one partner will play Iron (Fe), the other will be Copper (Cu), and their emotional baggage is Sulfate (SO4). Sulfate has a molecular charge of negative 2, meaning it has two extra electrons.

Copper: Blah, blah, blah, oh yeah? Well at least your oxidizer helps you in the kitchen. Mine thinks I’m a maid.

Iron: Ha! HA! Let me ask you, Copper, who has been paying your car insurance for the last 6 months?

Copper: I’ve been looking on Craigslist to find a job for a YEAR! Cut me some slack.

Iron: *scoff* And you’ve been on 2 interviews in the last 3 months. What do you do all day when I’m at work?

Copper: I do lots of things!

Iron: Like what? You wake up at 11.

Copper: Seriously, fuck you. I didn’t even want to come to this party. These are all your friends.

Iron: You know what? We’re not doing this here. Not now…

(Both exit in sulky huff)

Aaaand scene. What a bummer, these two are. What you’ve just been privy to is the oxidation/reduction reaction which is written symbolically as:

Fe + CuSO4 --> FeSO4 + Cu

Copper starts off connected to Sulfate, the negative baggage. Iron actually WANTS that baggage because Iron (and Iron will never admit this if you ask it) actually derives satisfaction from taking Copper’s sulfate. The exchange reduces Copper and oxidizes Iron.

Copper is now in a reduced state because it has a less positive charge. This is only one example of oxidation and reduction. These types of reactions happen ALL the time in nature. This is what takes place in the process of fermentation to make beer. Not with Iron and Copper because then you would be poisoned and die, but you get the gist. Little yeast oxidize organic material and in turn give off carbon dioxide and alcohol to get you buzzed. Now if you’ll excuse me, I must get back to being chemically awesome! Toodle-ooo.

Guess who has two thumbs and a new job?

2008-11-03T21:00:00.000-08:00

THIS GUY!

Thank goodness. I've been searching high and low for the past 3 months. Job hunting is a drag. I'm happy it's over.

To read a fun piece I wrote for a friend of mine, go to:

http://fierceandnerdy.com/?p=2501

Somebody DID give me a job! Yay new job!!

Gypsummmm, ummmm, ummmmm, uhhhh.....

2008-09-02T17:51:00.000-07:00

My apartment is now messy. Parts of it are messy anyways. I’ve moved out of my office at USC and now have several stacks of books and folders and binders and boxes filling my rumpus room. Yes, I have a rumpus room. It is for rumpusing purposes – instrument playing, record listening, personal dance parties, canoodling, and my very loud paper shredder used to annoy my neighbors. Don’t you wish you had a rumpus room too?

On top of one of the piles in my rumpus room is a small book labeled “Brines and Evaporites” by Peter Sonnenfeld and P.P. Perthuisot. I thought that today we might talk about one popular Evaporite: Gypsum. Would you guess that Gypsum is?

a.) A mineral
b.) A rock
c.) A Gypsy plagued by vocalized pauses
d.) A valuable construction material
e.) a, b, and d.
If you answered e., pat yourself on the back! Let’s learn more about this versatile substance!

Gypsum’s chemical makeup is calcium + sulfate. If you want to get technical about it (and I know you do), it’s really calcium sulfate dihydrate meaning that a few water molecules are thrown into the mix (CaSO4 2H20*). Gypsum is very, very soft with a hardness of 2 on the Moh’s scale, which the scale for geologists who poke and scratch minerals as part of their jobs. You can scratch Gypsum and leave a mark with your fingernail. Gypsum can grow in pretty patches of crystals. See:

What's confusing is that sometimes gypsum is a mineral and sometimes gypsum it is a rock. From my knowledge gypsum the mineral has grown crystals as seen above, and gypsum the rock is a sedimentary rock that precipitated out of a solution during evaportation. Don't forget, there’s also alabaster to continue confusing the picture. Alabaster is another name for gypsum which is often used to create vases, bowls, and priceless naked sculptures!

Calcium (Ca) and sulfate (SO4*) are elements present in seawater and tend to get together when mineral laden bodies of water evaporate. These two really like each other since calcium has a +2 charge, and sulfate has a -2 charge. Evaporation of seawater or some mineral-laden body of water can leave behind Evaporites (evaporate, Evaporite, easy to remember, yes?). Halite, also known as rock salt, is an evaporite too. If and when a large body of water evaporates, vast deposits of gypsum can be left behind. Just look at the White Sands National Monument in New Mexico, USA.

Wow wee. Look at all that gypsum. All that scorching-hot, throat-parching, stinging-the-eyes-when-the-wind-picks-up gypsum. Glorious.

Gypsum is really quite fantastic. I didn’t even get to Plaster of Paris or drywall, but that means we’ll have something to talk about next time. See you then!!

Pics:
1.) http://hyperphysics.phy-astr.gsu.edu/Hbase/geophys/gypsum.html
2.) http://flickr.com/photos/gembone/360013210/
3.) http://www.corazonliving.com/slides/White%20Sands.jpeg

* I can’t figure out how to have blogger give me subscript numbers, so just pretend the 4 in sulfate and the 2 in water are little.

Thesis is to job as Map is to _________.

2008-08-28T14:58:00.000-07:00

De-do-do-do
De-da-da-da
Is all I want to say to you

De-do-do-do
De-da-da-da
They're meaningless and all that's true

Oh hello! Holy Sweet Potatoes, guess what? I finished my Masters Thesis! YAY! I've been waiting for it to show up on USC's digital archive site because I'm so super proud of it I want to share it with you. It's not there yet. Ho, boy. It's a doozy.I done wrote a purdy thesis. Iron-Clad, serious science stuff from a professional. Here's my favorite figure from it - it's a map I made of my research area:

Doesn't it look great? Can I tell you about how much of an enormous pain it was to make? First, I scanned an old Ocean Drilling Project map into Photoshop (which I barely knew at the time. Now me and Photoshop are like that [fingers crossed]). Then I digitally erased a whole bunch of stuff on that scanned map and overlayed a *hand-drawn* map I made myself with the dark contour lines you see. That's right, hand-drawn oldschool style contour map. Finally, I copied and pasted the stations icons out of powerpoint (bless that powerpoint) and labeled everything and voila! My beautiful map is just how I wanted it.

I'm sure there are zillions of easier ways to do this *cough*hire-someone-else*cough*, but I made it from start to finish and that's pretty darn satisfying to me. Job. Well. Done!

And on the subject of hiring someone else, now I need a job. What happened to the Phd, you ask? I'm not sure if I want a PhD right now. The research at that level just gets so specific and I'm concerned about painting myself in a corner as far as a career goes. And academia...well, I'm just not sold on the idea that it will make me happy down the road. Call it wishy-washy or quitter or whatever. I call it my decision and I'm sticking to it. Here's to new beginnings!

Aquifurry

2008-04-24T13:51:00.000-07:00

Hi friends!! Want to know more about aquifers!? Good, I thought so.

An aquifer is typically some layer of permeable rock or unconsolidated material like gravel or sand wherein water that trickles down from the earth’s surface tends to hang out for a while. We like aquifers because by tapping into an aquifer via a well we get fresh water to drink, irrigate crops, cook, clean, fill water balloons, etc.

Aquifers can come in a couple of different flavors, two of which are confined and unconfined. A confined aquifer typically has a layer of finer grained sediments on top if it called an aquitard. This aquitard layer serves as almost a cap on the aquifer below it. Water can still permeate an aquitard, but it does so very…very…slowly. If water isn’t let through at all, the layer is called an aquiclude. Aquitards can be layers of clay or silt or whatever fine grained sediment you fancy.

Unconfined aquifers are just like what they sound: an aquifer that isn’t confined by an aquitard. These aquifers seem so footloose and fancy free. No, but they do contain water that is still a viable source for wells and such. Unconfined aquifers can sometimes be found living above confined aquifers, but below the water table. Think of unconfined aquifers as the confined aquifer’s noisy upstairs neighbor who’s always tromping around in high heels at all hours of the night. I have one of those neighbors. Man, I hate those jerks.

There's your quick and dirty look at aquifers. Ta-Da!

image ref: http://tinyurl.com/4cvhfy

Heeeyyyy, I know you

2008-04-16T15:55:00.000-07:00

It's so good to see you! You look great, have you lost weight? Hmm? What's that? What have I been up to, you ask? Well, I've been really busy. I finished my thesis, helped write a funding proposal, went to a conference, got my PhD comittee squared away, went on some dates with some gentlemen, played some roller derby, ate some cheeseburgers, redecorated the apartment, bought a moped...oh, but enough about me. What have you been up to? Uh huh. Uh huh. Oh, my. In your head? The size of a walnut? That's terrible. Oh, ok. You've got to run. I understand. I'll see you again soon and I'll have more stuff to tell you. Right now I have to get to work on my thesis edits. Awww, I missed you too. I'll see you soon. Love, Paris.

Rock Haikus

2008-01-28T10:43:00.000-08:00

They come from inside
They were molten, now they aren’t
They are igneous

Phaneritic rocks
Large crystals live in this kind
Visible crystals

Aphanitic rocks
Small crystals you cannot see
Small, like the aphid

Silica, felsic
Light color, low density
Continental Crust

Iron rich, mafic
Darker, higher density
Oceanic Crust

Igneous rocks have
many different names we learn
Vocab is a pain

And now for Box Models!

2008-01-11T11:44:00.000-08:00

I’ve been set to the task of constructing a box model for my silica work in the North Pacific. A box model starts by thinking of your system as a 3 dimensional box, hence box model. Then you start adding up all the ways silica can enter your box and subtract from that all the ways silica can exit your box. Assuming that your box is in steady state (i.e.: there’s no tremendous buildup of silica in the box) then everything coming in has to equal everything going out. Simple, right?

Here’s my box model:Things going in = things going out. Now we get to apply numbers to this model and this is where I’m boned. The difference between choosing a number like 190 or 195 is a big deal in these calculations and to choose the right number means choosing the number my advisor can live with. I would storm on ahead and finish this already if only I knew that I wouldn’t have to do all this work over again once we decide that 192 is a more appropriate number than 193. And so, dear reader, such is the life of a graduate student. I guess we’ll have to find something else to do in the interim. Like read some science papers, but I’d rather watch baby monkey videos.

Sediments are so sedentary

2008-01-08T18:24:00.000-08:00

Have YOU ever wondered how much sediment is dropped onto the seafloor in our world’s oceans? Have you ever wondered how it varies as you move away from the coasts? What’s that? You HAVEN’T!?? To be fair, I guess it’s not a topic one broaches on a daily basis, but today I’ve had to think a little about this question so I’ll tell you.

Sediments (i.e.: dirt, broken shells, fish poop, dead phytoplankton, and whatever else constitutes all the crap floating in the ocean) collect on the seafloor on the order of centimeters per thousands of years. That means that hardly anything makes it to the seafloor. Near the continent (land) we get a larger sedimentation rate, like a few millimeters per year in areas where junk is roaring out of rivers and where productivity in the surface waters is high. But out in the big, deep Pacific you’ll find maybe 2 or 3 centimeters of sediment accumulation for ONE THOUSAND YEARS. That means when you scoop up a sediment core, you’re looking tens of thousands of years into the past.

I had this idea while sifting through mud cores on our last expedition to bag up all the mud that we didn’t need and package it so as to sell it to fancy ladies for spa treatments. Could you imagine? People would eat that shit up. All I’d have to do is use lots of words like “vital” and “nutrients” and “exclusive” and “silky”. So long NSF, hello Lancôme. Not surprisingly, it was very nice mud. My hands were very soft after working in the lab for several grueling hours. I kick myself for not actually following through with this genius scheme.

Say it like you mean it. Or say it like you want to confuse everybody.

2007-12-05T14:38:00.000-08:00

In the interest of trying new things here at Get Your Science On!, I’d like to shorten things up a bit. I’m trying to be more concise in my life these days. So instead of having few long winded discussions, we will have several short discussions encompassing one point. I came across this sentence in a paper: “If biological fractionation effects driven by secular changes in siliceous production and preformed silica concentrations in paleosurface waters were the cause of local changes in downcore Ge/Si_opal, then there must also be spatial gradients in Ge/Si_opal across paleoproductivity gradients in today’s Southern Ocean and across those inferred for the glacial ocean.”

I WANT TO KNOW WHAT THIS SENTENCE SAYS!

“If biological fractionation effects driven by secular changes in siliceous production and preformed silica concentrations in paleosurface waters”

Translation: If little phytoplanktons that lived in the oceans way way back when liked to take up more or less germanium (see: "Bizzy Bee" in the May section) because of the abundance or lack of silica in those ancient oceans…

“were the cause of local changes in downcore Ge/Si_opal”

Translation: and those phytoplanktons mucked up what we’re seeing in THIS mud core.

“then there must also be spatial gradients in Ge/Si_opal across paleoproductivity gradients”

Translation: then we must be able to find this mucking up in other places

“in today’s Southern Ocean and across those inferred for the glacial ocean”

Translation: like in the Southern Ocean today or someplace a lot like it.

You see what I have to contend with? That was just one sentence out of a 10 page paper filled with sentences just like it. It's enough to throw your hands up in the air in exhaustion.

Dear Get Your Science On,

2007-11-15T09:39:00.000-08:00

I’m writing this to tell you something I should have told you about a long time ago. I’ve been cheating on you. I’ve been cheating on you with a Sketch Class offered by the Upright Citizens Brigade Theater. Wait! Before you turn your back on me, let me explain.

It started a few months ago. You are I were doing good together, but face it, we had become routine. I write you Tuesdays and Fridays, and you…well, you’re a blog so you don’t do much of anything. I’ll admit that my typing fingers longed for another challenge even as we discussed isotopes and iron fertilization and earthquakes and I just wanted something more. Then along came Sketch Writing Class. Sexy, time-consuming, Sketch Class. I thought to myself, “I’ve never been with a Sketch Class before. I wonder if it’s like how everyone says it’s like”. I couldn’t resist the allure of something so different, so non-scientific. I enrolled. I enrolled, but I immediately regretted my decision! My humor doesn’t translate well to a 3 page sketch. I don’t care about “the game” or “buttons”. I don’t want to sit around a table and spend 3 hours listening to other people’s sketches, especially when there’s nobody cute to look at. But the saddest part is that all my sketches were about science and nerds and field trips. I couldn’t escape you. The whole time I was with Sketch Class, I was thinking about you.

I’m so sorry, Get Your Science On!!! How could I ever betray you? I don’t want to be with Sketch Class anymore, I want to be with you. Let’s go back to the way things were, huh? Just forget about all this nonsense and go somewhere nice. Take a vacation together. Please, just take me back and I promise things will be how they were before I met Sketch Class.

I miss you.
Love always,
Tabitha

Places of Interest

2007-10-30T11:34:00.000-07:00

The class I TA for is learning all about the geologic history of Western North America this week. Much like Janice Dickenson, western North America has seen a lot of action in the past and now bears the scars of its wild ways. Here are a couple of places that I find especially interesting:

The Salton Sea:

The Sea itself is nothing more than a topographic low caused by the divergent plate motion which is ripping Baja away from the continent of North America. This man-made cesspool came to be in the early 1900s when water was diverted from the Colorado River whilst engineers were building an aqueduct intended to serve agriculture in the Imperial Valley. Its creation was an accident, but the sea became a popular tourist destination in the 1920s and 30s because it is hotter than shit out there in the desert. Water fowl also love the Salton Sea and the lake was stocked with fish like Tilapia. The problem with the Salton Sea is that there is no more freshwater input so as evaporation whisks away water, all the dissolved salts and chemicals stay behind and become more concentrated. The salinity of the Sea is upwards to 40 parts per thousand (ocean water has about 35 parts per thousand). Throw in some harmful algal species and a lot of dead fish and you have a tragically disgusting situation.

Yellowstone National Park:

ref

Yellowstone is a SUPERVOLCANO! Or Supaire Volcano. Yellowstone Park in northwestern Wyoming sits atop a large caldera that heaves and hoes up and down about 1.5 centimeters per year. This “breathing” in and out of the caldera makes me nervous, for one, but is indicative of what’s going on in the magma chamber below. As pressure increases and decreases, the land rises and falls. This will happen until the caldera explodes and obliterates everything from here to kingdom come. The good news is that eruptions are estimated to be several hundreds of thousands of years apart. We humans can blow ourselves up by then, thank you very much Yellowstone.

Willamette Valley, Oregon:

What’s so interesting about this little valley? Well, besides being a rich and bountiful place to grow agriculture, this valley was formed by the backlogging of water after the Great Missoula Floods. The Missoula Floods are floods of unimaginable proportion that roared across western North America at the end of the last glacial – about 18,000 years ago. Seriously, you can’t even imagine how crazy huge these floods were. So huge that the entire Willamette Valley served as a holding tank for water that was dumping into the Pacific Ocean via the Columbia River. Looking at the satellite image gives you some perspective of how much water that must have been. It was a lot. Like, a lot a lot.

See, places can be fun sometimes!

I've got a fire in my heart for you, California

2007-10-24T11:37:00.000-07:00

Holy Jesus, friends. Your favorite Geochemist has had a fire in her heart and a fire in her backyard for the past few days, both of which appear to be all but extinguished. We will brush aside the topic of the former, but on the topic of the latter we will discuss today why the empty regions of Southern California are ablaze yet again.

If you’ve been living underground for the past week, you’ve missed the pseudo Apocalypse that has born down upon Southern California. FIRE SEASON. I grew up in Southern California and can remember years and years of yellow skies and soot dust and chapped lips and sneezing. Fire Season coincides with the appearance of the Santa Ana Winds, also known as The Winds That Drive Everybody Apeshit.

The picture above is a super-great illustration of how the Santa Anas form. We get a region of high air pressure building up in the Great Basin between the Sierra Nevadas and the Rocky Mountains. This air escapes the Great Basin via the Mohave Desert and continues on toward the ocean, following topographic lows like canyons and valleys (I’m looking at you, Los Angeles). The air is heated by adiabatic compression.

Adiabatic compression means that when you squeeze something, it heats up. You should be somewhat familiar with this if you’ve ever pumped up a bike or car tire. Even though you’re not heating the tire directly, pressurizing the gas inside increases the tire’s temperature. The diagram above illustrates this point with a Pressure vs. Volume plot which includes two isotherms (or lines of constant temperature). Any point that lives on an isotherm has the same temperature even if it has a different pressure and volume than a neighboring point. Adiabatic change means that you’re going to jump from one isotherm to another by changing your volume or pressure. Increase in volume and you decrease the pressure, so you’ll jump to a lower isotherm (cooling). Decrease the volume and you’ll increase the pressure, in which case you’ll move up to a higher isotherm (heating).

That’s why the Santa Ana Winds are so gosh darn hot and dry. Until next time, keep safe out there, gang.

Again with the Iron

2007-10-12T12:40:00.000-07:00

Let's continue with our look at dissolved iron in the oceans, shall we?

You might be asking, “Wait a minute, lady. If phytoplankton are so great and iron in the ocean is so scarce, why don’t those phytoplankton evolve already and use something else that is more abundant? Like, Magnesium, or whatever.” Good point. Iron availability in the oceans is down around the part per billion concentrations, so why do organisms still use it? The answer is that iron is such a great electron acceptor, phytoplankton make due with the little that is around. The whole subject of electron donors and acceptors and how biology makes use them gets a little complicated. It deals with things like enzymes and biochemical pathways and other biological topics I don’t really understand. Biologists understand these things, so touché Biologists. You’ve bested me at understanding chemosynthesis, but I’ll smoke you when it comes to Eulerian and Lagrangian water transport.

Iron comes in two flavors: Ferrous and Ferric. Ferrous iron (Fe+2) is soluble, meaning that it will hang out in the ocean until some little critter or phytoplankton snatches it up. Ferric iron (Fe+3) is insoluble, meaning that it will form a molecule with something else (usually oxygen) and “precipitate” out of solution. Ferric iron is pretty much useless to phytoplankton. They are beggars AND choosers in this game.

Up until about 2 billion years ago, the Earth’s oceans were anoxic (lacking oxygen). Ferrous iron was super abundant in the Earth’s early ocean because there was no oxygen around that would oxidize it. All of the little algae and cyanobacteria and whatever else that was evolving prior to 2 billion years ago loved having all this Ferrous iron around, they were in hog heaven! That is, until photosynthesis showed up. Photosynthesis ruined the Ferrous iron party by pumping the atmosphere full of free oxygen. Atmospheric oxygen ended up in the oceans by way of air-sea gas exchange and all that lovely, useful Ferrous iron was oxidized to Ferric iron. It precipitated out of the Earth’s oceans and created something that geologists know as “Banded Iron Formations”These formations can be found in places like Australia. The bands are layers of iron oxides (rust!) that sank all the way down to the seafloor as photosynthesizers oxidized the Earth’s atmosphere all those billions of years ago. So on the one hand we can thank those prehistoric photosynthesizers for filling our atmosphere with oxygen, but on the other hand they kinda shot themselves in the proverbial foot by creating a world where Ferrous iron is in short supply.

But, like I said, iron is so great at what is does that biology makes due with what little is around. Biologists even have a term for the overindulgence of iron by phytoplankton – it’s called “luxury” uptake. Luxury, not in the sense of a Diatom relaxing on the tiniest chez lounge you can imagine, but in the respect that it will take up more iron than it needs and store it for later use. Whenever I hear the term "luxury uptake" I can only think about obese single celled organisms wearing monocles and driving Rolls Royces. Luxury, ha ha.

Iron, man

2007-10-09T11:30:00.000-07:00

I have to read a lot of science papers. Science papers are not fun to read because they are confusing. They don’t have to be confusing, but unfortunately most of them turn out that way. This is something I have a beef with. I want to know what these science papers are saying, I want to know what your models do or what your data shows, but I can’t do that when you don’t paint a clear picture for me. I could go on and on about my hang-ups with this topic, but instead I would like to describe to you a science paper in my own words. Today, we take a look at a paper by Boyd, et al. that was published in 2007 in Science, titled: “Mesoscale Iron Enrichment Experiments 1993 – 2005: Synthesis and Future Directions”. I think by doing this, I will digest this paper a little bit better and you’ll get to find out some interesting things pertaining to the field of oceanic iron research.

So what’s the deal with iron anyways? Well, phytoplanktons in the ocean need iron just like you and I. They become wimpy and anemic without iron just like we would. This is a big, BIG topic right now seeing as we (humans) would very much like to increase the amount of primary production in the oceans. Primary production, that is to say photosynthesis, is one way that we might save our asses from the looming Greenhouse Apocalypse because plants remove CO2 from the atmosphere and turn it into oxygen. Yay plants!

The ocean is FILLED with plants in the form of phytoplankton. The problem is that phytoplankton don’t grow everywhere, they can only grow in places that have the nutrients they need. Nutrients like nitrate, phosphate, silica. There are a couple places on Earth where it seems like conditions are perfect for phytoplankton growth, but nothing is going on. These places are called High Nutrient Low Productivity zones or HNLP zones. The Southern Ocean is a HNLP zone.
Conditions should be perfect for primary production in the Southern Ocean. Lots of cold water, lots of nutrients, plenty of mixing, and sunlight for part of the year. Problem is those phytoplanktons don’t grow there. Why?

A guy by the name of John Martin proposed that phytoplankton don’t grow in these regions because they are limited by iron. I should take this opportunity to say that iron is a really, really, REALLY hard thing to measure in the oceans because you so many possibilities for contamination. It took years for researchers to figure out why their iron numbers looked so wonky. The problem is that iron is everywhere – your boat, your collection devices, your bottles, your cables, your hands…you yourselves are a tremendous source of iron. When you’re measuring iron in parts per billion concentrations, every little bit counts. This problem was somewhat remedied by instituting clean rooms and anal-retentive practices that would limit the amount of iron contamination. But nothing is perfect.

Anywho, John Martin and those folks lucky enough to work with him set sail for the Southern Ocean armed with tons and tons of iron sulfate that they intended to dump in the water and see what might happen. What happened was exactly what he predicted – phytoplankton went apeshit. They grew like crazy and their bloom lasted for weeks. The picture below is a satellite image of chlorophyll (an indicator of phytoplankton) in the region where the ship dumped its load. You can see that the bloom pretty much follows the ship tracks.

(image from http://www.csa.com/discoveryguides/oceangard/images/soiree.jpg)

Is the story over? Fuck no, but I have to get back to work. Tune in on Friday for more on John Martin and oceanic iron fertilization…

PS: This article has a pretty cool description of John Martin and his research. Check him out. He was a cool dude who unfortunately passed away in 1993 right as his work was coming to fruition.

This abstract really needs to lighten up

2007-10-05T12:02:00.000-07:00

I wish all scientific writing was as easy as these little discussions that we have here at Get Your Science On. It would be wonderful if I was allowed send off papers to Science and Nature in the format of a casual conversation amongst friends. I do not, however, believe that Science or Nature would appreciate jokes about poop and masturbation peppered in to serious data analysis. They really don’t know what they’re missing.

My advisor surprised me this week by telling me I “should really” submit an abstract for this conference dealio in early March 2008. Something I’ve learned over the past 2 years is that when an advisor says “ You should really ______”, it means “You have to _______” in advisor-speak. Advisor-speak is a dialect that spans all human languages and is only understood by graduate students. It takes time and patience to understand this dialect and by the time you fully comprehend its subtleties, you’re done with grad school. Anyways, the conference is for the American Society of Limnology and Oceanography – ASLO for short. ASLO is a nice conference for oceanographers because you get to see colleagues from around the nation and check in on what fun and interesting things your buddies are up to. The only catch is that it’s being held in Orlando. ORLANDO, FLORIDA. Blech. My family and I went to Orlando once when I was young and did all the requisite Disneyworld business. I can’t say I remember much about it, but my grown-up opinion of Orlando is not a good one.

My abstract was submitted in time (a whole 4 hours before the cutoff time!), I paid my registration fee, so I guess I’m in it to win it. I thought I’d give you all a sneak peek at what it’s like to write a real scientific abstract. Here you go!

............................................................................

TITLE: Where does high Si originate in Cascadia Basin?

Deep waters in Cascadia Basin have silicic acid concentrations that may exceed 200 uM and show progressive enrichment northward, from the 180 uM in water entering at the southern end. The two possible sources of silicic acid in the deep ocean are (1) dissolution of biogenic opal in seafloor sediments and (2) hydrothermal seeps. These sources have different germanium to silica ratios and δ30Si values. Ge/Si ~ 0.7 umol/mole and δ30Si > +0.9‰ for biogenic sources. Hydrothermal sources have Ge/Si of 11-35 umol/mole and δ30Si ~ - 0.3‰. Core incubations determined the average silicic acid flux from seafloor sediments is 0.81 ± 0.05 umol m-2 day-1 and benthic flux is characterized by a mean Ge/Si of 0.6 – 0.7 umol/mole. The observed values in deep waters (>2500m) indicated inputs with Ge:Si ratios of 0.7 umol/mole and δ30Si of +1.4‰ (similar to that measured for sedimentary diatoms and more enriched than other deep Pacific and hydrothermal waters). These results indicate that opal dissolution must be the dominant source of silicic acid added to Cascadia Basin.

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Droll, huh? Nary a fart joke to be had.

Time is what you make of it

2007-09-28T11:40:00.000-07:00

I have a confession. My confession is slightly embarrassing considering that I work in the Earth Sciences: I don’t know my geologic timescales. When someone tells me a fossil is from the Ordovician or the Precambrian, I have no idea what they are talking about. Was that 10 million years ago? 167 million years ago? 1.92 billion years ago? 569 million years ago? I DON’T KNOW! There’s a reason why I went into Oceanography and not Paleontology – I can’t keep these ages straight. The worst part is that my students have to learn the geologic timescale in their general education class. So while they have everything memorized for midterms, I’m stuck with my finger up my nose trying to remember if the Pleistocene came before or after the Pliocene. That being said, why don’t we take today and learn the geologic timescale together? It’ll be fun!! You get to learn something new and I get to relearn the timescale for the 10th time and pray that my drinking binge this weekend won’t erase my memory. Again.

It would be fair to mention that I DO know some of these Eras and Periods. I know that the Cambrian was the time where all sorts of life appeared on our planet. The Cambrian Explosion was the explosion (!) of life in a very anticlimactic way. It was during this time that we find lots of fossil evidence of worms and sea-bugs and sponges and even more worms, but this time with teeth. Earth sounds like a pretty gross place back in the Cambrian, right?

So the Cambrian explosion occurred around 544 million years ago and I’m going to ignore (for now) the times before the Cambrian which are the Proterozoic, Archean, and Hadean. These 3 are Eras when the Earth was juuust forming. Most Paleontologists ignore these times in Earth history because it’s really really hard to find shit that’s 2-3 billion years old. The life that did exist were things like algae, bacteria, single celled organisms, viruses, and so on. Borrrring.

Moving on, the Cambrian/Precambrian boundary was around 544 million years ago, and then the next exciting thing was the Permian/Triassic boundary which was about 248 million years ago. An aside here: Paleontologists have a pretty clever way of defining the boundary between eras and periods. What they do is look at some sedimentary rock formation that’s got fossils in it, start at the bottom of the formation (where the oldest fossils live), work their way up to the top of the formation (where the youngest fossils live), and wherever older fossilized critters disappear they go “Aha! There must have been some cataclysmic event around this time that wiped out most life on Earth and allowed all these new critters to take over!” I don’t exactly know where they get the numbers from – must be by age dating rocks within the formation using some radioactive isotope. Reason # 122 why I'm not a Paleontologist.

We’ve covered the Boring Era (Precambrian), and then the Gross Period (Cambrian), and then we get into more exciting Eras and Periods like everyone’s favorite the Triassic and Jurassic (248 mya and 206 mya, respectively). Maybe at this point we should create a mnemonic device to help us remember most of these. If we can’t get the dates right, we can at least get the order right. Starting from the oldest first...

A…………………..Archean
Pizza……………….Proterozoic
Comes……………..Cambrian
On………………….Ordovician
Sunday,…………….Silurian
Delicious!..................Devonian

My…………………Mississippian
Pizza……………….Pennsylvanian
Precludes………….Permian
The…………………Triassic
Jaggoff………………Jurassic
Competition.…….Cretaceous

Put…………………Paleocene
Everything…………Eocene
On………………….Oligocene
My…………………Miocene
Pizza……………….Pliocene
Please, …………….Pleistocene
Harold…………….Holocene

Uh, well. That's a start. You know what? I'm just going to keep this chart handy in case I'm in a life threatening situation where I need to know when the Pennsylvanian was EXACTLY. Yes, that sounds like a good plan.

Happy Friday!

Nu(trients) to you

2007-09-25T14:30:00.000-07:00

You may have noticed there’s a lot of ocean out there. A lot of ocean that I get to explore while being carted around in big, smelly boats, gathering up hundreds of tiny bottles filled with seawater. My lot in life is as a Chemical Oceanographer. I love what I do, but man there’s a lot of ocean out there. A lot of ocean with a lot of chemicals in it; chemicals which I (and folks like myself) try to make sense of. Specifically, I look at the nutrients in the ocean. Nutrients like silica, phosphorous, and nitrogen. Let’s discuss today about what we might find in the depths of the ocean with respect to these important nutrients.

Let me begin by saying that the best and easiest way to make your point to a room of scientists is to make a graph. Scientists LOVE graphs. They love graphs more than they love New Balance and The North Face, which is a very telling statement if you’ve ever seen a scientist. Scatter plots, bar graphs, pie charts, whathaveyou. If you can put it in a graph, they’ll love you forever. When we plot nutrient concentration vs. depth in the ocean, we end up with a plot like this:It doesn’t matter if this is a graph of phosphate, nitrogen, or silica, most nutrient curves typically have this shape. Why, you ask? Well, let’s start from the top and move our way down.

Oceanic phytoplankton can only live in “The Mixed Layer’. Remember that phytoplankton are plants so they need sunlight to grow and nutrients to be happy. Depending on how murky your water is, sunlight can only penetrate about 60-100 meters down, at the most. The Mixed Layer is phytoplankton Party Time. Such Party Time, in fact, that they tend to use up every last molecule of available nutrients in the surface ocean – that’s why we have a concentration of practically zero in the top 10s of meters on our fancy graph above.

Particles like poo-poo are loaded with avalible nutrients. When that stuff falls through the mixed layer, the nutrients get recycled back into the water column. Below the mixed layer, the nutrients redissolve and are up for grabs again! It’s at this depth that we see a maxima in nutrient concentration.

The rest of our nutrient profile is pretty bland. As you can see, we have a pretty constant concentration except for a wee increase in the deep sea. This increase is no figment of your imagination or analytical error. It was a real head scratcher for ocean chemists for a long, long time because it shows up everywhere in the world and gets bigger as you move from the Atlantic to the Pacific. This, my friends, is evidence of the Thermohaline Circulation. If you were unfortunate enough to have seen “The Day After Tomorrow”, you would have gotten at least the jist of the Thermohaline Circulation – the deepwater “conveyor belt” that moves water from the surface ocean in the North Atlantic all the way around the world until it pops back up in the North Pacific. This current is super slow, but transfers heat all over the world, and apparently deadly storms, and Dennis Quaid, and then we all move to Mexico. The point is that the deep water is really, really old. Because it’s really old, it’s collected tons of particles that have rained down into it as it makes its way around the world. This gives us that slight bump at the very bottom of our graph.

See, now you know how to explain a nutrient profile to your friends! Use this knowledge wisely, as the power of oceanography is unwieldy at best.

Nocturnal Emissions

2007-09-21T12:45:00.000-07:00

We talked a little bit earlier in the week about photons and their behavior as waves. Like we said, photons are little packets of energy that behave sometimes like waves and sometimes like particles. They propagate like waves, with different wavelengths having different associated energies. Color, radio waves, gamma rays, x-rays – all of these types of waves (and so many more) make up what’s known as the Electromagnetic Spectrum. But what about the particle behavior of photons? Well, my friends, today we’ll take another look at photons, but this time we examine how they act like particles.

Atoms are very excitable. Atoms and photons interact much like overweight children in a Bouncy Castle. Say your neighbor is having a very rowdy, very annoying party for their 5 year old. For this little thought experiment, imagine that the Bouncy Castle is an atom and all the kids inside are electrons. Everybody is having a good time in the Bouncy Castles, until the chubby kid arrives. The chubbiest kid at the party (who at this moment is outside the Bouncy Castle) represents one photon. He tanks down some cake and ice cream and barrels into the bounce house with a shitload of energy. He’s so energetic, in fact, that one of the other kids (an electron) gets shot out of the Bouncy Castle upon his entrance.

The parents that are loosely chaperoning (drinking at) this party see the commotion and promptly eject the cubby kid, thereby allowing another not-so-chubby kid back into the Bouncy Castle.

This is pretty much what happens to an atom when it gets hit with a photon. The atom starts at Ground State (step 1) – everything relaxed and normal, all of the electrons hanging out in their proper Electron Shells. When a photon hits the atom, the atom absorbs it and in order to conserve its (the atom’s) energy, it has to eject an electron. The atom is now in excited state (step 2). As soon as that electron is fired out of its shell, another electron moves in on the territory and the atom goes back to ground state (step 3). Again, the atom has to conserve energy, so when that electron moves in during step 3, a photon has to be emitted.

How can an atom get excited, you ask? One way is to burn it. Some chemicals burn different colors at juuuust the moment you ignite them. You can see purples and blues and greens, and remember that the difference colors you see represent photons with different energies. Harkening back to the Electromagnetic Spectrum, different colors equal different wavelengths which in turn means different energies. Get it?

This whole burning-with-different-colors thing is how Astrophysicists determine the chemical composition of celestial bodies that are far far away. The fancy name for it is Spectroscopy. As an aside here: my declared major when I transferred to UCLA was Astrophysics. But I hated the undergraduate advisor so much that I switched to Math. Astrophysics is certainly a wonderful field populated with very smart and interesting people, but I’d take a month out at sea over a month trapped in an observatory any day.

Do the Wave

2007-09-19T10:13:00.000-07:00

We humans can’t see very well when we look far far into outer space. Sure, telescopes give us a glimpse at deep space, but we can only learn so much when we just use our eyes. Luckily there are plenty of other options when it comes to detecting electromagnetic radiation from outer space. Visible light is only one kind of electromagnetic (EM) radiation. We can broaden our view of the universe by using new-fangled instruments that will detect photons with various wavelengths. A photon is basically a little packet of energy. We call photons “packets” because you can’t really call them a particle and you can’t really call them a wave since they behave like both. They can be shot off from an atom the way an electron might be, but we can see them as light, with wavelengths that correspond to different colors. You could say that photons go both ways. They’re swingers, man.

Much like delicious ice cream treats, electromagnetic radiation comes in all kinds of different flavors. We’ve got photons with long wavelengths which make-up things like radio waves, micro waves, and colors like reds and oranges. On the other end of the spectrum we’ve got waves with really short wavelengths like gamma rays, X-rays, and colors like violets and blues. When we talk about wavelengths, we’re talking about the distance from peak to peak OR trough to trough on a wave.

Any wave (EM, ocean, crowd at football stadium) will propagate with a speed that is the product of its wavelength multiplied by its frequency:

velocity = wavelength * frequency

All types of waves in the electromagnetic spectrum travel at the speed of light which is 3 x 10^8 meters per second. That’s 670 MILLION miles per hour (if I did my math right). Crazy fast. So fast, in fact, that nothing travels faster than the speed of light. Yet.

A consequence of this whole traveling-at-the-speed-of-light thing is that the speed of light never changes. For our purposes, it’s a constant. This means that if you increase wavelength you have to decrease frequency and vise versa. So waves like gamma rays that have super small wavelengths have really high frequencies and are super duper energetic. Radio waves and Infrared waves with long wavelengths have lower frequencies. When we talk about frequency, we’re talking about how many waves hit you in a given amount of time. Where gamma rays are like “bam, bam, bam, bam”, Infrared waves are like “bam…………bam…………bam………….bam”.

As an aside here: you ever wondered why your car’s antenna is as long as it is? That’s because the wavelength of radio waves is about 100 centimeters – just about how long your car’s antenna is!

Please excuse me now. I have an appointment to receive a wedgie and be stuffed in a locker.

Snell ya later

2007-09-11T10:52:00.000-07:00

Snell's law was one of the first physical laws that I learned as a young, fresh faced undergraduate. OH, how time has made me jaded. It’s actually a very simple law that has to do with the behavior of light refraction through various mediums. Let’s explore this law, shall we.

You know how when you stick something like a straw into a glass of water, the straw looks kinda bent? You’re seeing Snell’s law in action. But before we talk about the law itself, we have to make sure everybody is on board with the definition of a “normal”. The normal is just an imaginary line perpendicular to any surface. Perfectly perpendicular at a 90 degree angle to the surface. Easy enough. The only tricky part comes in when you’re dealing with a curved surface like a lens.You can see from the diagram that the normal depends on where you are on the surface of the lens. We’ll come back to this in just a second because this is why lenses are so good at doing what they do.

Back to Snell’s law. Snell’s law says that if a beam of light moves from a medium of high velocity (like air) into lower velocity (like water or glass) the beam is going to be refracted TOWARDS the normal. We can see this in the picture below:
You can see that instead of traveling along its original path, the beam bent up towards the normal. The opposite happens when you move from a medium where the beam has a low velocity to one where the beam has a higher velocity, like moving from glass to air. In this scenario the beam moves AWAY from the normal. Now let’s check out what happens in a lens:
Do this to a lot of beams of light and you’ll be able to focus those beams onto a single point!
Ta-Da! Now that you understand the principles of Snell's law, you can feel good about being a juvenile misfit while you're burning a line of ants with a magnifying glass.

You are incorrect, madam

2007-09-07T11:31:00.000-07:00

Well my dears, it seems that I have steered you wrong (as per our discussion earlier in the week). To recap things, I was given some questions in one of my classes and chose to discuss the changing pH in the world’s ocean and how it relates to the uptake of CO2. I was of the opinion that this was a sneaky question seeing as the pH of the ocean is changing as we speak due to how seawater reacts with atmospheric CO2. While this isn’t totally incorrect (you like that double negative?), it’s not the answer that the proff was looking for. Turns out that the correct answer is that the world’s oceans have had a relatively constant pH since the last ocean anoxia event 10s of millions of years ago.

Ocean Anoxia Events (OAEs) are times in the earth’s history where the deep oceans lost most, if not all, of its dissolved oxygen. Lots of very smart people are spending very large amounts of money to figure out why these events occur because nobody has a straight answer just yet.

This is what an OAE is like: You ever been swimming in a lake? Chances are good that if you went in the summer, the upper couple of meters was nice and comfy; but if you swam (swum? swimmed?...oh, forget it) deeper you’d hit a boundary, below which the water gets really really cold. That boundary is called the thermocline and exists not just in lakes, but in oceans too.

thee thermocline

The effects of sunlight can only be felt, at most, 60 to 100 meters deep. We call this layer the surface ocean. Everything below it is considered the deep ocean. The surface ocean and deep ocean don’t transfer water that easily. Upwelling and downwelling are pretty much the only ways the water "communicates". All that warm stuff on top wants nothing to do with the cold and salty stuff on the bottom. The only way to mix them is via ocean currents that move various bodies of water all around the earth through the deep sea.

During Ocean Anoxia Events, the world’s oceans become a lot like that lake. Communication between the surface and the deep is cut off, which limits the input of dissolved oxygen to the deep ocean. Without that input, all the fishes, and jellyfishes, and sharks, and shrimps, and crabs, and microorganisms that live in the deep sea eventually “breathe” up all the available oxygen until there is no more. No more oxygen = no more life = mass extinctions.

The chemistry of deep waters gets really screwy when all the oxygen is gone. Chemicals like hydrogen sulfide appear in the deep sea and we get a condition that is known as “euxinic”. These conditions are bad, bad, bad for the life that we know and love but great for organisms that thrive in low oxygen conditions. So, to bring all this back home to the question of pH, yes, the pH of the world’s oceans has remained relatively constant for a long long time. That being said, I'm going to stand my ground and say that I wasn’t totally wrong. Meh, whatevs. "A" for effort, right?

Homewerk

2007-09-05T11:00:00.000-07:00

I have lots of things to do lately. New classes to take and teach, bright young minds to nurture with science, and thinking up new and creative ways to put off what I should really be doing. I’m taking a class called “Advanced Biological Oceanography”. Let’s break that down: Advanced – ruh roe. Biological – haven’t taken biology in years (poop sandwich). Oceanography – THIS I got nailed. We’re lookin’ at 1 outta 3. Part of this class is answering a few questions given to us in lecture. We got 3 questions last week:

1.) Why are the chemical properties of water (H2O) different than hydrogen sulfide (H2S)?
2.) How long has the chemical composition of the oceans remained constant? What is the evidence?
3.) How long has the pH of the ocean remained constant? What is the evidence?

Now, I’ll admit that I barely know earth history. I have only absorbed enough to nod at all the right times because I’ve been in close quarters with geologists for the last 2 years, and believe me when I say that close quarters with geologists can get a little rank. The poor microbiologists in this class couldn’t possibly know where to begin, bless their hearts. Can’t say I’m in much better shape, but I guess all I can do is my best. Let’s tackle one of these questions right now, shall we?

#3. Trick question. The pH of the oceans is currently changing due to uptake of CO2. The ocean is an enormous sink for CO2 on the surface of the Earth, taking up approximately 1/3 of anthropogenic (man-made) CO2 (1). As the ocean takes up this CO2, a series of reactions takes place starting with the production of carbonic acid (H2CO3), then bicarbonate (HCO3), then carbonate (CO3). Each reaction frees up a hydrogen ion:

CO2 (g) + H20 (l) <--> H2CO3
H2CO3 <--> H + HCO3
HCO3 <--> H + CO3

The more free hydrogen ions we have floating around, the lower the pH of our oceans. Remember that lower pH means more acidic. The evidence that the pH of the oceans is changing can be gathered from field measurements or by monitoring oceanic calcifiers. As the ocean becomes less alkaline, there is less of the carbonate ion around for these plants and critters to use to make shells and/or skeletons. Bad news for corals.

Well, that’s one down, two to go. Maybe Advanced Biological Oceanography won’t be that bad*.

1: Orr, J. C. et al. (2005). Anthropogenic ocean acidification over the twenty-first century and its impact on calcifying organisms. Nature 437, 681-686.

*Or it will be soul-crushingly hard.

Moron Potassium!

2007-08-31T10:53:00.000-07:00

Why not keep the ball rollin’ and delve deeper into the element with atomic number 19? Let’s go!

Potassium is represented by the letter K which stands for kalium. How we got about calling this stuff potassium is a sordid history which you can glance at here. Potassium has 3 naturally occurring isotopes (the percent abundance is in parenthesis): 39K (93.3%), 40K (0.0117%) and 41K (6.7%). So you can see that the majority of potassium is stable, with 19 protons and 20 neutrons. Just a wee bit of all the potassium that exists on this planet is radioactive Potassium, which has 20 protons and 20 neutrons.

Potassium-40 is a radioactive isotope that decays sometimes to Calcium-40 and other times to Argon-40. How can an isotope have two different daughters? Before we take this question to Maurie Povitch, let’s take a look at a few ways a radio-isotope can decay.

(REFRESHER! Protons have a positive charge and live in the nucleus of an atom; neutrons have no charge and also live in the nucleus of an atom; and electrons have a negative charge and whizz around outside the nucleus of an atom )

Alpha decay: This is when the isotope shoots off an alpha particle. An alpha particle is basically a Helium atom without any electrons (i.e.: 2 protons and 2 neutrons). As long as we’re on the subject of alpha decay, I should note that alpha particles have a short mean free path, meaning that they loose a lot of their energy a short distance after they are ejected from their mother-atom. So if an alpha particle hits your skin, it’s not going to do much damage. But if you eat or inhale alpha particles, you’re in trouble. They’ll get inside your stomach and lungs and cause all sorts of problems. That’s why you don’t want to eat or drink anything while you’re workin’ with alpha emitters, so take those tacos outside the lab!

Alpha Decay, with pizazz.

Beta minus decay: Also called “electron capture” because this is what happens when a proton turns into a neutron in the nucleus of your atom. The nucleus acts like a tractor beam and sucks in an electron which negates the charge on one proton.

Beta plus decay: With this decay method, the nucleus kick out what basically amounts to an electron, thereby turning a neutron into a proton.

There are a couple more decay pathways that I won’t get into. Anywho, back to potassium. Potassium-40 decays about 11% of the time by electron capture to Argon-40, and it decays about 89% of the time by beta plus to Calcium-40. We like it when potassium decays to argon because we can use these two isototpes to age date igneous rocks! When igneous rocks solidify, they’ll trap any potassium and any subsequent argon that is created by radioactive decay. Argon is a gas, but it’ll hang out inside the crystal lattice of a mineral just so long as that mineral isn’t heated. It gets to be tricky business if your rock/mineral *has* been heated, but don't worry your pretty little heads about it. Geochronomitry is in good hands.

Wow! Radioactivity, explosions, impotence…potassium really is pretty awesome!

Potassium is pretty awsome

2007-08-28T11:49:00.000-07:00

I had a bag of bananas baking in my car this morning. Delicious, soft bananas. All those bananas got me thinking about potassium and what an interesting element it is. So today, thanks to those bananas, we will look at a common element with some fascinating uses and behaviors.Potassium lives all the way on the left side of our periodic table in a category known as the Alkali Metals. The definition of alkali is “a hydroxide which dissolves in water to form a solution with a pH greater than 7; capable of neutralizing an acid.” A solution that is highly basic can be just as dangerous as a solution that is highly acidic. If you reach way way back into the memory of your 7th grade chemistry class (and ignore the boredom and embarrassment you probably experienced in said class) you’ll remember that acids and bases neutralize one another. I'm sorry you had to delve back to such an unpleasent time. Go to your happy place, go to your happy place.

Alkali Metals have an atomic configuration that makes them want to give up an electron. This quality them very very reactive. So reactive in fact that they must be stored in mineral oil for fear that they will react with any moisture lingering in the air. All Alkali Metals are reactive with water, and they become more so as you move down the column of the periodic table. Sodium is more reactive than Lithium, Potassium is more reactive than Sodium and Rubidium and Cesium, forget about it. Potassium, especially, is HILARIOUSLY explosive when it comes in contact with water. Just look at what this idiot ended up doing:

I can't tell how much potassium went in there, but it was probably an amount no bigger than a dime. Now, I’m all for reckless science (obviously), but this instructor could’ve gotten seriously hurt, or injured her students or blown up her classroom completely. Alkali Metals, in their purest form, are nothing to fuck around with. Luckily, you’ll almost never find pure sodium or potassium or (God help you) Rubidium unless you’re a chemist and you really need them.

Potassium is found in lots of things, including minerals! Minerals like potassium feldspars, also known as Orthoclase, are frequently found in Granites. Minerals with potassium in them are pretty pretty pink, like this:

One last note about Potassium is that the compound potassium nitrate (KNO3), also known as saltpeter, has a notorious reputation for what it does and does not do to the human body. Saltpeter is one constituent of black power gunpowder, but if urban legends are correct, was also used as an anaphrodisiac everywhere from mental institutions to sailboats. I'm not aware of any studies that prove or disprove these statements, but if WW2 has any say in it, I'm a believer.

Viva Potassium!!

I <3 the Mundane!

2007-08-24T11:18:00.000-07:00

I'm going to tell you about something incredibly mundane today: fitting your data to a line! Now before you go running off to Pink Is the New Blog, let me plead my case as to why you should care about the mundane. We often think of the mundane as being awful when really the mundane is awesome. Think of all the mundane things you spend time doing: eating, drinking, running errands, brushing your teeth, sitting around at work. I’d venture a guess that 80-95% of your day is filled with the mundane. But without the boring shit that we have to do each and every day, all the exciting shit that happens to us wouldn’t be as exciting, right? So let’s revel in the mundane as we continue today’s discussion.

As you now know from our last entry, I’ve got lots of data. I’d like to graphically represent my data so that I can show lots of people my findings and have them go “Ooooo, Aaaaa. Tell me, young scientist, what does it all mean?” I can then look like a smarty pants by explaining to them that by plotting some quantity on the X-axis (the horizontal line) vs. something else on the Y-axis (the vertical line) we can make BROADER GLOBAL IMPLICATIONS with this data. Scientists love to graph things. Anything and everything looks better on a graph. It also helps the scientist presenting the graph to summarize their findings in order to avoid needless rambling. Scientists love rambling almost as much as they love graphs.

Let's build a graph together to better illustrate my point. We talked earlier in the week about auto-analyzers and all that jazzy business of precision and why auto-analyzers are rad if you have a buttload of samples, but not that rad if you want high precision. The data points we're gonna use are gotten by pumping samples with known concentrations through your auto-analyzer. The auto-analyzer spits out what we’ll call an Arbitrary Number. Your results might look like this:

Concentration-------------------Arbitrary Number
0 -------------------------------0.000
38.41 uM -----------------------0.205
76.81 uM -----------------------0.410
101.51 uM ----------------------0.560

What we have in the left column is the concentration of our chemical in micro-Molar units. That’s 10^-3 moles per liter of solution and remember that a mole is 6.022 x 10^23 units (molecules or atoms), so we’re really talking about how many molecules are in our sample.

On the right is the Arbitrary Number that your auto-analyzer might display once it “digests” your sample. I say digest as an purely imaginative description because these machines do not actually feed on your sample. Or do they? Oh my.

Anyways, the next step is to arrange our graph. We’re going to put the Arbitrary Number on the X-axis and the Concentration on the Y-axis. If you reach WAY back into your mathematical memory, you’ll find an itsy-bitsy morsel of knowledge which tells you that when making a plot, the independent value goes on the X-axis and the dependant value goes on the Y-axis. Don’t remember? Well, I won’t hold it against you. Here is your data plotted by itself.

What happens next is that you, being the intrepid and fashionable young scientist you are, use the linear fitting function in Excel or some similar program to get a line running through (or close to) all your data points.
This line has an equation to it. Without getting into the nitty gritty of it, you’ll be able to use this equation to translate all the rest of your data into concentrations. All that’s left to do is eat Cheetos and let the auto-analyzer do its thing.

I think congratulations are in order because you just made your first calibration curve!! YAY!

Daaaaattttaaaaa....

2007-08-21T13:55:00.000-07:00

In a perfect world, we would all have perfect data. In a perfect world, all instruments would run smoothly and do what they’re supposed to do WHEN they’re supposed to do it. In a perfect world, all spreadsheets would be organized and all precision would be less than 1% and measurements would even be repeatable. Unfortunately, we do not live in a perfect world. Instruments of analyzation break and clog and sputter, spread sheets disappear, and scientists get the shakes in the lab after a long weekend of binge drinking, resulting in imprecise pippetting. If only the public new about all the shoulder shrugging and “Meh, good enough” data out there, you’d question the BROADER GLOBAL IMPLICATIONS you heard about in the news.

Let me tell you about my data:

My data comes from the North Pacific and was collected on a cruise that I was on last August. We collected water samples at all ranges of depths – from very very deep (~ 3km) to very very shallow (~10m). We collected hundreds of little bottles of water which we keep here, in a cold room, so that we can reanalyze that water for nutrients like silica, nitrate, and phosphate. All those bottles have lived in that cold room for about a year and will probably live there for another 40 years or so. Not that that’ll do anybody and good, it’s just kinda the way things go around here. I’ve tripped over mud cores collected in the late seventies in that cold room. Seriously, scientists don’t know when to let go.

I say reanalyze because all these samples were run on the ship last summer. They were run by a dude from a lab hired out by the University of Washington. This guy had an instrument called an auto analyzer, which does exactly what it sounds like it does. It analyzes things automatically, hooray! We like auto analyzers because they’re fast. No messy pippetting, no headaches of tinkering with your spectrophotometer, just load your samples in and the numbers come roaring right out. The problem is that with speed, you loose precision.

Auto Analyzers suck/rule depending on your situation.

Precision is the ability to repeat the same measurement and get the same result. So say you run one sample three times and you get 180, 182, and 179, you’re in good shape. We like precision more than speed because precision means we can make statements about what we see and have the wherewithal to back it up. You don’t want to go out on a limb and make some big dramatic statement when you don’t know how good your data is.

I’m currently having data problems because of this business with the auto analyzer and it’s crappiness in the world of precision. You see, I’m looking for differences in the realm of 4% so we’re talkin’ small changes in nutrient content seen over hundereds of water samples taken from hundreds of depths at dozens of stations. If this auto analyzer can make only make measurements precise to 2-4%, we’re in trubs. The error inherent in the measurement overshadows any real signal I could hope to find. Now I’ve got to go back through all this data with a fine tooth comb and make sure the differences that are going to lead to BROADER GLOBAL IMPLICATIONS are really real and not just a figment of analyzation. Doesn’t that sound like fun, kids*???!!!

*Answer = No.

The perils of Peru

2007-08-17T11:19:00.000-07:00

Hey gang - bummer news out of Peru this week. If you haven’t checked the news reports there was a major earthquake in the Ica province, which is about 125 miles south of Peru. It was a magnitude 8 that occurred at 6:40pm on Wednesday. You can read about what happened here. Not really a subject to make light of. Peru is a beautiful place filled with wonderful folks just tryin’ to get by and they’ve been delt a rough hand. I would be remiss to ignore this whole situation and get back to talking about helium 3, which I was going to do today. Instead I think it would be appropriate if we learned a little bit about what’s going on in Peru’s part of the world and why they got slammed with such a huge earthquake.

Peru sits snuggled up against one of the world’s gnarliest convergent plate boundaries. Remember that in the rhelm of plate tectonics, we’ve got 3 things plates can do: move apart from one another (divergent), crash into one another (convergent), or slide on by one another (conservative). Along the coast of South America we’ve got what’s called a subduction zone. Subduction zones are features of convergent plate boundaries where we’ve got one plate diving down underneath another

Some other major subduction zones around the world are over on the west side of the Pacific Ocean, nearby Japan (the Mariana Trench). We've also got the Aleutian Islands up in Alaska as well as along the coast of Washington and Oregon in North America which is named the Cascadia subduction zone. The Cascadia subduction zone is the reason why we have the Cascade mountain range right there (Mt. St. Helens anyone?).

The subduction zone along the West coast of South America involves the Nazca Plate and the South American plate. The Nazca plate is an oceanic plate which means it’s made up of dense stuff like basalt whereas the South American plate is made up of relatively light stuff like granite. Remember, these plates are in motion all the time because they’re riding along on the molten Asthenosphere underneath them, but they don’t move very much. When they do move, we get an earthquake.

Subduction zone earthquakes are so much bigger than transform fault earthquakes (ie: quakes on the San Andreas) because you’ve got a much much deeper fault which dips down into the earth at an angle. Let’s look at the figure below.
Ok, this might get confusing because we’re dealing with looking at the faults from the perspective of cross section. Imagine that you’ve taken a slice out of the earth way deep into the crust and are looking at the fault zones straight on. On the left we’ve got our transform fault (ie: the San Andreas). On the right we’ve got the setup as it is in a subduction zone (ie: Peru). Now, imagine that both these faults rupture the same amount, maybe 4 meters. Outlined in pink is the plane on which the rupture is going to happen. Because of the geometric setup (the hypotenuse of a triangle is always longer than the other two sides), the plane that ruptures in a subduction zone earthquake is larger than that for the transform fault. Larger plane of rupture equals more area of the fault broken and a larger area equals a larger earthquake. That’s why when faults at convergent zones rupture, they are such humongous earthquakes.

I’ll wrap it up by saying that if you’d like to help with relief efforts, check out this link to make a donation for the folks who need some assistance. Like I said, there’s lots of good people out there who could use a little help to get themselves out of such a crummy situation. All I’d hope for is that someone would do the same for me if I were in their shoes.

Hydrothermalitious

2007-08-14T12:37:00.000-07:00

The area I work in the North Pacific is nearby a feature called the Juan de Fuca ridge. We’ve talked a bit about plate tectonics in the past (see "The Tale of Alfred Wegener”) and up in the North Pacific is a little tectonic plate called the Juan de Fuca plate. Juan de Fuca was a 16th century Greek captain employed by Spain to chart a northern course from the Pacific Ocean to the Atlantic (thanks, Wikipedia!). He didn’t find such a passage, but what he did find was later named the Strait of Juan de Fuca which is that body of water that separates the Olympic Peninsula from Vancouver Island. Straits, plates, ridges, Lordy! What didn’t this guy get his named slapped on? When you have ridges, you have hot vents. Remember that ridges are the places where new crust is being formed as magma oozes up to the surface. Hot vents are those fun sea floor features we see on nature programs with all sorts of weird lobsters and tube worms growing around them. A sidennote here: lots of those critters (crabs, shrimps, lobsters) have no pigment because, well, what would be the advantage of having color in pitch blackness? When the submersibles get down there to take all those pretty pictures we see in magazines and on the Discovery channel, they blast the area with flood lights. All that light shocks the shit out of those critters and usually a ton of them die as a result. But before you get all worked up about this just remember that shrimps and lobsters and crabs are the bugs of the sea, so you shouldn’t feel any worse than you do squashing a cockroach. There, feel better hippy?

Moving on, all that hydrothermal activity leaves its mark on the surrounding water. One way to tell if you’ve got hydrothermal influence is by measuring 3He in the seawater. 3He is a non-radioactive isotope of Helium with 2 protons and 1 neutron. There is a shitload of it in the Earth’s mantle and it’s thought to have been trapped there as the Earth formed from hunks of spacerock mashing together. 3He is released in places where magma extrudes, like sea-floor ridges and hotspots (ie: Hawaii). Up in the North Pacific we indeed have a “plume” of 3He that extends from the Juan de Fuca ridge all the way into the mid-Pacific.
So what’s the big deal? Well, by sussing out the location of the plume we have an idea of how the water is moving around at this depth in this part of the world. The plume reaches out to the southwest and exists at a depth of 2000m. There must be some sort of current at 2000m that carries this 3He southwards and away from North America. That’s a start.

For me, I’m interested in understanding this plume of 3He because it coincides with the plume of silica my advisor and I are so interested in. Remember that silica is an ocean nutrient and can be pumped into bottom waters via hydrothermal sources. In the North Pacific we find 3He coinciding with lots of silica, but only in the northern part of the plumes. Once everything reaches the mid-Pacific the two plumes diverge: the helium plume stays a little north of the silica plume. So the question is: if these guys (both the 3He and the silica) are being pumped out of the Juan de Fuca ridged at the same time, at the same temperature, with the same water properties, why aren’t they sticking together as they get carried out into the Pacific? The short answer is that the silica isn't hydrothermal. The long answer will be avalible in dissertation form, and only God knows when.

Moron Earthquakes

2007-08-09T14:47:00.000-07:00

My new thing for Get Your Science On! is to keep a theme going throughout the week. This is easier for me ‘cause I don’t have to wrack my brain for a whole new topic, and I’ll just assume it’s easier for you because…well…it just will be. We talked a little bit about earthquakes on Tuesday and LOW AND BEHOLD what happened between now and then? AN EARTHQUAKE!

The New York Times reports: “The earthquake struck at 12:58 a.m (Thursday morning). Pacific time and caused no major damage. The United States Geological Survey estimated its magnitude at 4.6….The quake’s epicenter was located 3 miles northwest of Chatsworth and 7 miles northwest of Northridge, where a much stronger earthquake of 6.7 magnitude did major damage and killed more than 60 people in 1994. Today’s earthquake was followed by three minor aftershocks, according to the Geological Survey.”

How apropos. Let’s continue our discussion about earthquakes by turning our attention to the buildings they damage. You see, buildings are the problem here in earthquake country. If we could all live and work in yurts, things would be great. If a bunch of grass and felt falls on your head while you’re sleeping, it’s no big deal. But unfortunately yurts are not very practical workplaces, so we must turn to stone and steel.

A yurt.

Prior to 1933, buildings in Los Angeles were mostly made of unreinforced masonry. These buildings are usually made out of brick, adobe, or stone and held together by gravity. Unreinforced masonry doesn’t offer any resistance to shearing forces, so just like a stack of blocks these structures will topple over given sufficient shaking. Lucky for Angelinos is that there aren’t any of these buildings left in our city, or at least none that people live or work in. We don’t have these buildings around anymore because (as we talked about) the Long Beach Earthquake alerted everyone to the dangers of using unreinforced masonry for places like schoolhouses. Between 1933 and 1971 non-ductile reinforced concrete was the popular choice.

Ductility measures a material’s ability to deform without breaking. Something very ductile can be stretched and pulled and won’t snap apart. Think of pulling apart silly putty very slowly, that’s ductile. Most building built between 1933 and 1971 were of the non-ductile reinforced concrete variety, but after the 1971 San Fernando quake, we saw the rise of ductile reinforced buildings. The key difference between the two is the amount of confinement you get in your columns. We’ve all heard the term “rebar”, right? Rebar is stuff that makes up the steel skeleton of a building or structure. Ductile reinforced buildings have rebar vertically through a column but also rebar horizontally around a column to make kind of a cage. By having rebar wrap around a column, you can hopefully avoid column bowing that happens if/when the concrete making up the column crumbles during an earthquake.

This is a good example of what goes on inside you’re new freeway columns. Lotsa rebar wrapped around more rebar. We like rebar. Rebar makes the world go round.

Oi, the topic of building response to earthquakes is a broad one. I guess we’ll have to save the discussion of soft 1st floor for another entry because now it’s snack time! I’ve got cookies to eat, folks. I'll see you later.

In all seriousness...

2007-08-07T12:23:00.000-07:00

Hello Friends,

I’d like to take this time to make sure all the folks I care about are prepared for the coming apocalypse. If you’re reading this, I probably know you, and even if I don't I wouldn’t want you to die in a horrible manner. Usually here at Get Your Science On we're all about having fun, but today we’re gonna get you informed about what you can do in the event of an earthquake and/or natural disaster of a similar fashion. But first we'll inform ourselves with some history of earthquakes in the LA area.

Southern California hasn’t had a humongous earthquake in a while. The last major earthquake on the southern section of the San Andreas Fault was in 1857 and was a whopper with Mw of 7.9 (that’s Moment Magnitude [see “MAGNITUDES!” for a hilarious refresher]). Since Southern California wasn’t too populated at the time, damage was minimal and only a couple folks got killed in this earthquake. Next up was the 1906 San Francisco quake where the San Andreas Fault ruptured in Northern California and we all know the consequences of that quake. Major damage to the city of San Fran, loss of life, fires, carnage, the works. But the population of San Francisco was only 410,000 at the time. The population in Los Angeles County was almost 10 million in 2006 according to the census bureau. Yipes.

A recurrence interval is defined as the time that it should take between earthquakes on a fault. If the Earth's crust was clockwork, we could expect an earthquake flawlessly on time. But the Earth is fussy and mostly unpredictable. However, the recurrence interval at least gives us a heads up as to when we can start biting our nails over the possibility of The Big One. The southern part of the San Andreas Fault has a recurrence interval of about 150 years which means we should have a big quake right…about…NOW! Aww, don’t be scared. There are lots of things you can do to prepare yourself for an earthquake!

First of all, congratulate yourself on living in a city with some of the most stringent and thoroughly enforced building codes in the world. YAY! The Long Beach earthquake of 1933 scared the pants off the citizens of Los Angeles when several school houses crumbled because they were built out of unreinforced masonry. The earthquake struck around 6 pm so children weren’t in school, but if they had been it would have been a major, MAJOR loss of life. Ever since then, laws have required retrofitting of older buildings (brick, masonry) and ensured that newer buildings be designed with earthquake safety in mind. That’s not to say that buildings can’t or won’t crumble given sufficient shaking. Remember: Earthquakes don’t kill people, buildings kill people.

After Hurricane Katrina, I wanted to make sure I had enough supplies to last for a couple days in the event of a catastrophe in the Los Angeles area. I started with two big rubber tubs that you can buy at Target for under 10 bucks. Buy the lids too. I put water (5 gallons), canned food, A CAN OPENER (!), other long-lasting food items like ramen and soy milk (which you do want to replace after a year or so), eating utensils, a few sweatshirts (in lieu of blankets), extra shoes and socks, a flashlight, one of those dynamo-powered radios, batteries, first aid shit like gauze, band aids, disinfectant, ace bandages, and I think some cash. Unless I “borrowed” that cash for booze. Anyways, you get the point. Above all else GET WATER! Don't plan on relying on a Brita filter either, spend the $4 and buy yourself a couple jugs of drinking water. The rule of thumb is you’ll want about a gallon for everyday use until utilities can be restored.

There are lots of good resources on the web about how to make yourself a survival kit, just Google it! But don’t feel like you have to run out and buy some fancy premade kit. Use your common sense and you’ll do alright.

Cox!

2007-08-01T12:32:00.000-07:00

Coccolithophores (pronounced cock-o-lith-o-fors [keep giggling, perv]) are little guys that live in the sea. I say guys in a very casual sense since they are actually phytoplankton, which are plants, so they don’t really have any gender. What they DO have are these little plates or shields called coccoliths encircling them in what’s called a coccosphere. Just like Diatoms, these little phytoplankton are trying to not get eaten, so they build a protective coating to make themselves less tantalizing to grazing zooplankton. The coccoliths are made up of calcium carbonate, a VERY important substance for lots of folks in the marine sciences.
One incarnation of calcium carbonate is chalk. You ever heard of the white cliffs of Dover? The cliffs in southern England that face Continental Europe? They’re famous for being the first thing that lots of folks see when they cross the English Channel. I guess that’s a big deal when it comes to wars and stuff, but what do I know, I’m no historian!
The white that you see in this formation is mostly coccolith fossils. Tons and tons and TONS of coccolith fossils make up this geologic structure. There are some remains of sponges and corals thrown in for good measure.

Anyways, we talked a long time ago about these other phytoplankton called Diatoms (see “Die, Die Diatoms my darling”). Diatoms protect themselves with silica whereas Coccolithophores protect themselves with calcium carbonate. The thing to know about phytoplankton is that they are all competing for nutrients in the surface ocean. Plants need nutrients like nitrate and phosphate to be happy campers, just look at the main ingredients in fertilizer the next time you’re at Home Depot.

The good news is that diatoms and coccolithophores thrive under very different oceanic conditions. Say there’s a huge rainstorm in Southern California. All the river runoff, sewage spills, and general poopieness supply nutrients (and diapers!) to the coastal surface water. Like we talked about before, diatoms are really good at swooping in and taking advantage of all nutrients. Given proper nutrients, a diatom population can grow crazy fast, resulting in what we call a “diatom bloom”. Coccolithophores, however, grow well in lower nutrient areas. They can be found way out in the middle of nowhere, thriving in waters with super-low nutrient levels. Good for them because this means they can out-compete a whimpier phytoplankton and take control of vast areas of ocean.

So now you’ve gotten a peak at the ancient competition for ocean nutrients between Diatoms and Coccolithophores. Two phytoplankton enter, one phytoplankton leaves!

Keep on keepin' on

2007-07-27T12:58:00.000-07:00

Since we were talking about the San Andreas Fault earlier this week, I decided to make it easy on myself and stick with the same topic for today’s lesson. There’s so much wonderfulness to discuss when it comes to this, our most favoritest fault.

The San Andreas Fault is the reason behind all sorts of landforms we see across California. Let’s start by looking at a map of this guy:

Ahh, the lovely California. What should stand out to you when you look at this map are the mountains that follow along the red line (the trace of the San Andreas Fault). The presence of these mountains makes sense seeing as all this movement along the fault mooshes the Earth's crust together in and around the fault zone. The whole Basin and Range province in the western part of North America is an after-effect of the Pacific/North American plate boundary, but we’ll leave that discussion for another day. Totally different topic.

Anywho, start with your eyes on the northern most part of the red line and then trace the red line southwards, towards Los Angeles. You’ll get to a point just south of the Great Valley (the Armpit of California) where you’ll see that the fault curves a bit inland. This curve is called “The Big Bend” and causes all sorts of interesting things to happen, geologically speaking.

For one, the Big Bend is responsible for the uplift of the Transverse Ranges.

This range of mountains is an oddball because it runs East-West, while everything else around us (the Coast Ranges, the Sierra Nevadas, the Rockies, the Cascades) runs North-South. Why you ask? Well, think of the Pacific plate moving northward and rubbin’ up against the North American plate. It’s cruisin’ along, carrying with it all those rocks and houses and dogs and buildings and burrito shops that exist west of the San Andreas. At the Big Bend, however, all that stuff is crashing into one another instead of smoothly moving along past one another. That seemingly innocuous curve in the fault has created a big, fat convergent zone in the area around the Big Bend. This convergent zone includes the Los Angeles region. Lucky us!
Along with the Transverse Ranges, we get the Garlock Fault out of all this Big Bend business. The Garlock is one of the larger lateral faults in California. If you’re ever flying north from Southern California, you can actually tell where this fault runs visually if you look out your airplane window. Pretty neat, huh? Make sure to point it out to the person sleeping next to you by saying “Hey, look look! That’s the Garlock fault! It’s a left-lateral strike slip fault that defines the boundary between the Mojave block and the Sierra Nevada/Basin and Range province!” I advise to also make sure to spit a lot when you talk and maybe sneeze on them once or twice because you are a nerd and should behave thusly.

NEEEERRRRDDDD!

Food and Faults

2007-07-24T11:46:00.000-07:00

Alright everybody. Let’s shake off the cobwebs and get back learnin’, shall we? Today we’ll talk about a place that we all know and most of us love: California. Specifically, we’re gonna look at how the San Andreas Fault was born. It’s kind of a weird story, but an important one to know for the sake of understanding why California looks the way it does. And there will also be a food analogy, so read on!

Remember back when we talked about plate boundaries? The places where those big tectonic plates crash into and move along with one another? No. Well, let’s remind ourselves before we move on.

There are three types of plate boundaries: divergent (pulling apart), convergent (crashing together) and conservative (rubbin’ against one another). An example of a divergent plate boundary is the East African Rift, of a convergent boundary we’ve got the Himalayas, and for our conservative boundary we’ve got the good ole’ San Andreas Fault.

For most of the last 600 million years, the western part of North America was a convergent plate boundary. An old old plate that doesn’t exist anymore called the Farallon plate was happily subducting underneath North America (see Figure). What happened was that there was a pointy bit of the Pacific/Farallon plate boundary that rammed into the North American subduction zone about 30 million years ago and everything went apeshit. When that pointy bit hit North America, the subduction zone along the western margin started swallowing up a divergent zone (where new crust is being made). Instead of one outdoing the other, the whole thing just fell into a new regime altogether and we got a conservative plate boundary. Why, you ask? I don't think we have a good explination as to why we got the San Andreas out of this mess. Or at least I don’t know anybody that knows why. It’s like taking a hot dog and smashing it together with a hamburger and ending up with sushi. Crazy!
The sushi that we ended up with is the San Andreas, the big mother of all faults in California. Unless you’ve been living in a cave or on the East Coast or are totally oblivious to all that surrounds you, you probably know that this is the fault that gives everybody the jitters. And rightly so, it’s a big fuckin’ fault that has caused a lot of problems in the past. The San Andreas Fault serves as the boundary for the North American plate to the East (what the rest of America is attached to) and the Pacific plate to the West. Yes, that means in a few million years Los Angeles will be sittin’ pretty right next to San Francisco. Don’t frown, San Francisco. Surely by then we will have engaged Iran in nuclear conflict so you won’t have to put up with anything more than the mutated remains of model/actress zombies looking for temp jobs.

Zing! It’s good to be back!

I know, I KNOW!

2007-07-20T08:49:00.000-07:00

Sorry I have been lame and not posted about science in a while. Shit has been busy for your favorite Geochemist latley. Vacation, divorce, vacation, walking dogs, vacation, spreadsheets, vacation, cartoons, and cheese! You know how it goes. Looky here: I'm heading back to the office on Monday and will start up writing you more science things, ok? My little heart swells with happiness that my friends love learning about the boring shit I work on. Thank you for your patience, I assure you that it WILL be rewarded.

In the meantime, head on over to www.chiefmag.com for a fancy article about zombies and physics written by yours truely.

Love,
Tabitha and Paris Killton

Silly-ka

2007-06-27T12:50:00.001-07:00

Silica is a nutrient in the ocean. Silica is used by little phytoplanktons called Diatoms. We like phytoplanktons because they take away all the bad, yucky CO2 we’re pumping into the atmosphere. We want to know about silica so we can know about phytoplanktons so we can know about CO2 uptake (see flow chart below).

SILICA --> DIATOMS --> CO2 UPTAKE --> BROAD GLOBAL IMPLICATIONS!

I am running samples for Silica today. And I ran samples for Silica yesterday. And I will probably be running Silica samples tomorrow. How do you run Silica samples, you ask? Well, I’ll tell you!

We use a technique called colorimetry. In a nutshell, we add a little bit of our water sample, add a cocktail of hazardous chemicals, pump the mixture into a machine called a Spectrophotometer and presto-chango we get an absorbance reading! Absorbance is a number that makes no sense until it’s put in the context of a standard. Here, let me explain.

Imagine that you are a fancy-pants scientist with a very expensive and very sensitive Spectrophotometer. Your Spectrophotometer has a beam of light built somewhere in its complicated interior. When you stick something in front of that light, the little reader inside the Spectrophotometer says “Hey, that asshole put something in front of me. This is how much my beam of light has changed.” You record this number. Please dismiss any disparaging comments made by your scientific instruments because this senario imaginary and scientific instruments don’t talk. But if they did, they would be grumpy.

Now about this standard business – a standard is just a sample with a concentration that you know precisely. You want to use a couple of standards with different concentrations so you can get a good range of values. In your imaginary lab, you’ll run your standards and say to yourself “A standard with concentration X gave me an absorbance reading of Y”. When you do this for all of your standards you’ll end up with a nice linear relationship between absorbance and concentration. You’ll get yourself a simple equation that you can pop all of your meaningless absorbance readings into and get out very useful concentrations and then make lots of charts and tables and powerpoint presentations with your data.

What we’re dealing with here is described by Beer’s Law. This is a serious scientific law with important implications and has nothing to do you with you doing a keg stand at your frat brother’s 23rd birthday party last year so quit snickering. Beer’s Law relates Absorbance (what your little spectrophotometer reads out) and Concentration (what you are trying to get). Beer’s law says:

I1 / Io = 10^-A. where A = l*c*k (the little ^ tells you that -A is an exponent)

Break it down!

Io is the intensity of the light you start with, I1 is the intensity of the light after it has passed thru your sample (see figure), A is the absorbance (what your instrument reads out), l is the path length of the beam, k is your “absorbance coefficient” (whatever that means), and c is the concentration in your sample (what you want).

In a perfect world you would know all these things. You would know your beam path length and your initial intensity and all that shit. But the big secret is that science is imperfect. Your spectrophotometer is gonna get bumped around and glassware is going to get dropped on it or samples spilled on it or cheeto crumbs mashed into it somewhere. This is why you use the ole’ standards trick 'cause now you can avoid having to use Beer’s Law. See, scientists aren’t perfect either. We just plan ahead because we know how sloppy and clumsy we really are.

Shipboard etiquette

2007-06-06T11:41:00.000-07:00

Let us turn to the all important science of human relations. Specifically, the science of human relationships while in a confined and isolated environment. Like a boat. There is a lot more to being an oceanographer than throwing big and expensive instruments overboard, you have to know how to cope with crew and fellow scientists while at sea. Both parties are entirely different and usually keep to their own. Here are some helpful hints should you find yourself on a long research cruise or, similarly, being smuggled to China for sweatshop labor. Let these tips guide you so that you won’t be fed spermburgers in the galley, or shanked in the back during your watch shift, or included in the mutter rants of the surly chief engineer. And trust me, they are ALL surly.

* Never throw up in the bathroom. Only throw up overboard. I don’t know why, but if you toss your cookies in the bathroom everyone gets mad at you.

* Front of the boat is the bow, back of the boat is the stern.

* If you’re facing the bow, starboard is on your right, port is on your left. You can remember this because “port” and “left” both have four letters in them.
* Let the captain talk to you. Some are friendly, most are not. Feel out the situation for yourself before you start gabbing about how early it is or how cold you are or how choppy the water is. He’s gonna think you’re a pussy if you start in with the complaints. And he’d be right.

* Anything that looks like a hose is typically important.

* No sandals on deck, hippie.

* No farting on deck. Wait till you’re someplace enclosed and in close proximity to the most annoying member of the science party. Preferable the cold storage room.

* Scientists, as a rule, are more annoying than crew members. Shocking, I know.

* Someone will always know what you’ve been looking at on the community computers. Always

* Don’t press any buttons, especially not if they’re flashing. Tell someone else about it.

* Do answer a phone if it is ringing nearby.

* Don’t talk too much.

* Do get your work done and show up for your watch shift on time.

* Do bring your own alcohol supply IF you are working on a US research vessel.

* Do take advantage of the open bar when working on Canadian, German, or Russian boats (for reals!)

* Don’t eat anything out of ANY refrigerator EVER!

* Don’t accept any compliments/favors/candy from members of the crew unless you intend on sleeping with them.

* Two movies to never put on in the community movie room: Apocalypse Now and Maid in Manhattan. Both will make you extremely unpopular.

* Don’t roll up to the chief engineer with a bunch of bolts in your hand and ask him if they are important. Even as a prank.

* Do get some exercise while you’re at sea. Just look at the crew.

* Don’t eat Doritos while working on the computer.

* Don’t eat Doritos while working with any scientific equipment.

* You know what? Give the Doritos a rest, why don’t you.

* The ocean is a beautiful place and deserves your respect. No peeing off the stern.

There, that should get you through a few days. Let your common sense guide you the rest of the way.

Bizzy Bee

2007-05-25T14:02:00.000-07:00

I like to keep things professional here at Get Your Science On, but today I’m tickled because my thesis is getting easier to write by the minute. I’ve got my eyes on the prize, the prize being a trip to NYC in July that is bought and paid for. I’ve just gotta turn this bitch out and then the liven’ is easy*.

So I’m gonna personalize the lesson for today and delve into what I’ve been working on so diligently. Let’s start with my research area: the lovely Cascadia Basin.Cascadia Basin is an underwater feature nestled in the North Pacific off the coast of Washington, Oregon and Canada. It’s pretty deep (~ 3000m) for not being so far offshore and it gets deeper as you move from the north to the south. As you can see from the map above, it’s cut by Cascadia Seachannel which runs north/south. You can think of seachannels as basically underwater canyons. HUMONGOUS canyons that make the Grand Canyon look like a baby.

If you’ve been with me from the beginning, which I think is only one person, you’ve read “Science Lesson #1: Oceanograph-me”. I told you a little bit about what I’m doing in this part of the ocean, but let me back up and explain things more thoroughly.

There is a shitload of the nutrient silica in this part of the world. Silica is what little phytoplankton called Diatoms use to make protective coatings called frustules. We like diatoms because they’re plants that can photosynthesize and wisk away some of the CO2 we are pumping into the atmosphere as we burn fossil fuel. Good guys. People like my advisor (and therefore me) want to know why there is all this silica in the North Pacific. Does it have to do with having a ton of diatoms, or is it because of something else?

There are two ways to get this much silica into the waters of the North Pacific. One way is to pump it through the oceanic crust via hydrothermal vents. You’ve all seen these things. They look like this:
Another way to get all this silica is by the dissolution of those diatom frustules as they fall through the water column. This is a two part process because not only does the silica dissolve as it makes it’s way to the seafloor, but whatever solid chunks make it to the seafloor continue to dissolve as they’re sitting around. Lots of biology = lots of silica.

How do we tell where our silica has come from? We look at another element called germanium. Hydrothermal vents pump out all sorts of chemicals, one of which is germanic acid (GeOH4). If you’ve got water that has been thru a hydrothermal vent, you’ve got yourself a ton of germanium. On the other hand, when diatoms make their little frustules, a little bit of germanium sneaks in there with the silica. Not much, but just a little.

What I do is jump on a big boat and collect water from all different depths within the basin. I take this water and analyze it for silica and germanium concentrations and then plot it up on a graph like this.
Looking at the picture, if we’ve got water with silica that is hydrothermally derived, the majority of our data points will cluster on a really steep line. If we’ve got water with silica that is from dissolution of diatoms, our points live on a much shallower line.

Sounds easy right? Oh, but that’s where you’re wrong! There’s so much nit-picking and number crunching and migraine inducing data reduction that goes on when you want to make a graph like this. Always remember that the first 4 letters of analytical chemist are ANAL. And I am tits deep in it, folks. Back to work!

*TM: Le Bomb

Motion through the Ocean

2007-05-23T14:05:00.000-07:00

Things move through the ocean in funny ways. Chemicals, nutrients, fish poop, whathaveyou. This stuff doesn’t just sink, but it moves along laterally with the currents too. Advection and Diffusion are two ways that things move through water and will be our topic for discussion today.

Advection is considered “Directed Velocity”. Just movin’ along in a straight line. How we describe advection is by flux. Advective flux is velocity (in meters/time) multiplied by Concentration (in moles/volume). The units of flux are moles/area-time.

Let me refresh your memory on what a “mole” is. A mole, in the chemistry realm, is a shitload of atoms (6.022 x 10^23 atoms to be exact). We can convert from moles to mass if we know an element’s atomic weight.
Look at our periodic table of the elements. See that number with a bunch of decimal places behind it? That’s the atomic mass. One mole of that element weights that many grams. For example, the atomic weight of Germanium is 72.59 so a mole of Germanium weights 72.59 grams. That’s 20.74 eightballs of Germanium to a mole. Don’t do drugs, kids.

Advection is a great way to describe stuff that is sinking. Diffusion on the other hand tells you about how things are spreading out. Diffusion is “Random Motion”. Remember that whenever you have a big glob of something that is really concentrated, like pee-pee in a swimming pool, it wants to move from an area of high concentration to low. We describe diffusion using Fick’s First Law.D stands for “diffusivity” and is in units of area per time. This law is also really great if you want to describe eddy transport. Eddies are big, swirly, chaotic regions of fluid movement. You can see them when you put cream in your coffee. The fluid mechanics within those eddies are hard to describe because the movement is so random, but the transport of particles via those eddies can be figured out using Fick’s first law.

Want to know more about this mysterious Fick? Adolf Eugen Fick was a 19th century
German physiologist who defined laws that we use for diffusion. He also invented the contact lens.

Kind of an intense lookin’ dude. It’s interesting that the man who invented the contact lens came up with laws that we use for Geochemistry. Laws that I will be grilled on during my Qualifying Exams. Thanks buddy.

Liquefacination

2007-05-21T12:56:00.000-07:00

Liquefaction is a big word for something that is pretty simple.

Liquefaction happens when you take a bunch of unconsolidated (loose) sediments, like sand, get’em wet, and then shake the shit out of ‘em. Wet sand might be fine on its own, but once it’s shaken (like during an earthquake) the sand looses its resistance to shear stress and behaves like a fluid. As you can imagine, this causes a lot of problems in the realm of engineering and structural design. You might think “Well, no big deal. I’m sure structures are built to withstand this by sinking the foundation deep into the ground”. Unfortunately this is not the case around the world. The US enjoys pretty strict building codes and organizations that are paid to enforce them. Such is not the case in places that can’t afford to be as stringent about building safety or just don’t have the time to think about the buildings they live in.

This is what liquefaction does.

The picture above was taken after the Niigata Earthquake in 1964 (click here for a map). There was a magnitude 7.5 earthquake offshore that triggered a tsunami, but luckily the loss of human life was minimal. The apartment buildings in the picture are still totally intact, not much structural damage. Just tipped over. Kind of amazing, isn’t it?

Not all towns affected by liquefaction are that lucky. Just check out this newspaper illustration made after an earthquake struck Port Royal, Jamaica.
Port Royal was a popular pirate pit stop in the 17th century where debauchery reigned! I remember being told once that it was the inspiration for the port *his lordship* Johnny Depp puts together his crew of ruffians in the first Pirates of the Caribbean movie. It might as well have been, but don’t quote me on that. Anyways, the town was built on a sand spit and when an earthquake hit in 1692, a big chunk of the city literally sank into the ocean. During the shaking, the ground turned into sandy slurry and swallowed people up whole.

Warning! Stop reading if you are a squeemy baby! Probably the most horrifying part of all this is the people who were trapped in the sand once the shaking stopped. You see, without the shaking the sediments go back to normal, so anyone who had any part of their body trapped in the sand when it was liquid was crushed as it solidified. You probably can’t see it in the picture, but there are little people stuck in the ground and dogs eating the heads of the deceased. Gruesome!

So that’s liquefaction. What else is there to say about a process that swallows people whole and causes buildings to tip over? Liquefaction: the sporadic killer.

Don't soil yourself

2007-05-18T12:54:00.001-07:00

Soils are fun. I guess. Maybe not so much fun as important. Think of all the things that a good soil provides us with: soft squishy grass, agriculture, potted houseplants, mud pies, earthworms, and shallow graves. You’d think that there’s not much to soils, dirt is dirt right? But you’d be wrong sir!

Soil is divided into five horizons:

O-horizon: O for organics. Lots of loose debris like dead leaves and dead asshole bees that will sting you even though they're dead.

A-horizon: The darker layer just below the O-horizon. Mixture of organics and sediment. Lots of live bugs.

B-horizon: More sediment than A-horizon. Lighter color, less organic material

C-horizon: Less of what we think of as “soil”, more weathered bedrock – bedrock being the super hard stuff that is way under the soil. Something like granite or slate or gneiss (see “Rocks for Jocks”)

R-horizon: Unweathered bedrock.

Soils are classified kinda like sedimentary rocks: according to their grain size. You’ve got fine stuff like clay and silt, then sand of various sizes, then gravel, cobble and finally boulders. What you do when you’re an engineer is construct a graph like this called a grading curve:

On your y-axis you have the % that passes thru a sieve of a particular size, also considered “percentage finer”. On your x-axis you’ve got grain size on a logarithmic scale (see "Science Lesson #4: MAGNITUDES! for a refresher on logarithims). Over on the left side of your x-axis you have itty-bitty grains like what would be in clays and silts. But as you move over to the right side of the x-axis you’ve got sediments the size of rocks and pebbles and the like.

Let's do a thought experiment: Say you’re in charge of classifying a soil that something big and important will be built on. Like a new burrito shop. How do you do it? Start by collecting a soil sample and running through a sieve that’s pretty porous (i.e. large holes). Drop the soil in the sieve and see how much comes out the bottom. If it’s a lot, meaning that your soil is relatively free of big rocks and pebbles, you say to yourself “this soil is 100% finer than the size of this sieve”. You move on to a smaller size sieve. About 80% of your sample comes out the bottom therefore 80% of your soils is finer than that sieve size. You keep doing this until you get to a sieve that is so fine none of your soil can get through. At that point you’ve got 0% finer and CONGRADULATIONS! You’ve constructed a grading curve.

Knowing what kind of soil you’re building on is important for a multitude of reasons. Moisture causes a lot of problems because certain types of clays start to behave like putty when they’re wet. Or you can get a soil that doesn’t compact very well or looses cohesion. Lots of engineering problems arise when you’re dealing with soil. Drainage, plumbing, septic tanks, gas and electrical lines are all things that you don’t want bad soil to muss up. So I guess soil is pretty important after all. Don’t ignore soil or soil will ignore you!*

* It pretty much does this already.

Opinion Time!

2007-05-16T10:55:00.000-07:00

The science that I do is within spitting distance of climatology. Literally. The Climatology lab is on the 2nd floor and I’m on the 3rd floor so I’m constantly dropping loogies on those snooty tree-huggers. No not really, but oceanography and climatology are closely related. So closely related that I end up getting a lot of questions about climate change and global warming. I think it’s a good thing that people want to inform themselves on this subject from a real science perspective and not just the alarmist banter of popular magazines. So here’s what I think…

People like Al Gore have their hearts in the right place. He is being tutored in a very difficult subject by the very best minds in the field. He is a public figure and revered enough to garner the attention of the masses. And, come on, he was on Futurama so he’s awesome. Unfortunatley, some of the ideas he harps on have not been fully validated yet. I'm not saying that they won't be, it's just that some of his claims are a wee bit premature. For example: we get a lot of information from ice cores. Scientists take a slice of the core, look at the gas trapped in there, look at the isotopes in the water, and important implications follow thusly. Problem is that the gas and the ice are not the same age. It's really hard to get the precise age of that gas. There's all this hullabaloo right now about the claim that the rise in CO2 caused warming at the end of the last glacial or if warming started before the rise in CO2. It's a case of the chicken or the egg: warming then CO2, or CO2 then warming? Not clear just yet.

The Earth is warming, that’s a fact. The heart of the matter is whether or not we’re experiencing warming solely due to our own actions or if there are other natural processes involved. Like Milankovitch cycles. The Earth is very special planet and has gone through some dramatic periods of warming and cooling. What we forget is that humans have been around for climate change already, like during the Medieval Warm Period where the ice sheet on Greenland melted just enough so the Vikings could settle there and have agriculture. That didn’t last too long, and eventually the ice came back which made Greenland not that enticing, even to Vikings.

To bring this all home: there’s probably little, if anything, we can do now to halt the effects of all the greenhouse gasses we’ve been pumping into the atmosphere. The Earth will change, but like always humans will adapt. Unfortunately the folks at the bottom are going to get the shit end of the stick, like always. Developing nations will have more and more problems with water supply and it will be very sad because more well off countries probably won’t do much in the way of helping out. The world itself will be fine. Humans will just end up being a messy blip in geologic time. And then in a few billion years when the sun expands and obliterates the planet, it won’t really matter will it?

Happy Wednesday!

Nothing personal, Milankovitch

2007-05-14T15:09:00.000-07:00

One thing that my paleoceanography teacher harped on A LOT this last semester was Milankovitch theory. Milankovitch, Milankovitch, Milankovitch. We talked about it so much I kinda hate Milankovitch, which is dumb because he died almost 50 years ago. I’m sure he was a good enough guy, it’s just that that class made me cranky.

Milankovitch was a Serbian engineer and mathematician who put together a theory about why the Earth goes thru cycles of glacials and interglacials. You see, nobody knows why the Earth has these long, cold periods called glacials. Finding out why the Earth goes thru these hot and cold periods is a big deal to researchers right now since we’re faced with the looming possibility of total climate annihilation!

To better predict the future, climatologists are looking at the past. The last glacial ended less than 20,000 years ago, which isn’t very long in geologic time. During glacial times is when we had awesome beasts like mastodons and saber tooth tigers, but unfortunately it provided the premise for the movie “Ice Age” and therefore contributed to the salary of John Leguizamo.

Milankovitch proposed that we get cycles of glacials and interglacials because of the Earth’s orbit with respect to the sun. We have 3 flavors of variation:

1.) Eccentricity – has to do with how elliptical the earths orbit is. Sometimes the Earth’s orbit around the sun is more circular than at other times. Further from the sun = less solar energy = colder. Eccentricity varies on a 100,000 year time scale.

2.) Obliquity – the Earth is tilted a little bit on its axis. Sometimes the Earth sits more up and down, but sometimes it’s more slanted. Obliquity varies on a 40,000 year time scale.

3.) Precession – imagine a top spinning around. Or a dradle (ooooo! I went there) You get a little bit of wobble as it spins around. The Earth does that too and the wobbling is called precession. This process affects the Earth’s orbit on a time scale of about 20,000 years.

Problem is that none of these mechanisms fit perfectly with the records of past glacial and interglacial cycles. It’s not like every 40,000 years and BOOM! The Earth gets super cold. Glacials happen because of a combination of factors, a combination that will make someone rich when they figure it out. But Milankovitch theory has not been totally poo-pooed yet, it’s still got its valid points. So props to Milankovitch, even though I’m totally sick to death of hearing about him.

Best Science Paper Ever.

2007-05-08T14:02:00.000-07:00

I... I'm at a loss for words. Read it for yourself.

19 centimeters!?

Final Project = Antarctica + ?

2007-05-04T13:37:00.000-07:00

I have a final project to finish before Tuesday for my Paleooceanography class. Paleoceanography is the study of the ocean’s past. This subject encompasses everything from ocean temperature to circulation to primary production to chemistry. It’s a pretty cool subject, if you like the oceans.

The instructor gave us an assignment that is broad and meandering, which totally blows, but I think I've got an idea that will win him over. Let's discuss it, shall we?

More and more studies are coming out saying that warming around Antarctica happened BEFORE the rise in carbon dioxide after the last glacial (in your face, Al Gore!). If this were the case, we should be able to use tracers of sea-ice coverage around Antarctica to get a time frame of when all this warming happened and compare it to the rise in atmospheric CO2. Antarctica was covered with even more ice than it is now during the last glacial. This ice extended way up north of the actual continent and into the South Seas.

If you cap off the ocean around Antarctica with sea-ice, like during a glacial, you screw with the ocean’s ability to exchange gases with the atmosphere. Gases like carbon dioxide. As we come out of the glacial, the world starts to warm and this sea ice will start to melt. We would like to know the timing of the melting of this ice and compare it to the timing of the increase in atmospheric CO2. One way to tell the timing of this melting is that as the sea-ice melted, it dumped a lot of crap onto the seafloor. Crap that includes the tests of specific diatoms. These diatoms are WAY different than the regular diatoms that live in the salt water. If you can get a sediment core, look at how much of these sea-ice diatoms are present at any given time AND when they disappear, you should be able to make some fantastic claim about the presence of ice around Antarctica. Ta-Da!

Sidenote! Doesn't Antarctica look like a smiling rhinocerous? Now you'll never forget how to draw this, our most neglected continent.

Cornfused? Me too. But somehow or another I’ve gotta sort this out before Tuesday. I'm so fucked.

In the midnight hour, she cries MOR, MOR, MOR

2007-05-02T11:13:00.000-07:00

MOR stands for Mid Ocean Ridge. These are exactly what they sound like: ridges in the middle of oceans. Sometimes they’re not exactly in the middle, so the name is kinda false advertising, but that’s what they’re called none the less. The important thing is that they are regions where new oceanic crust is oozing up from the Mantle. The discovery of these ridges validated Alfred Wegener’s theory of plate tectonics and evolved our understanding of the world around us. Good stuff all around.

If we look at the picture below, we’ll see that ocean ridges wrap around the globe like the seams on a baseball. They are areas of divergence meaning that they’re spots where our plates are moving apart from one another. If we look close up at an ocean ridge we can see the effects of all this pulling apart (see below). We’ve got Normal Faults because we’ve got extension in the crust. In the very very middle of the ridge (the ridge “axis”) we’ve got kind of a saggy region which is called the Rift Valley. If you were to find yourself in either Iceland or East Africa, you could see an actual Rift Valley. Touch it. Walk through it even.

Plates don’t move very fast so it’s not like these ridges are ripping open violently. We do have new magma being extruded at the surface, but in a very quiet way. When new magma pops up, the old crusty stuff has to get outta the way to make room so the rocks on either side of the ridge gradually move away from the ridge axis. This is the mechanism that we call sea-floor spreading. Sea-floor spreading tells us a few very important things. For starters, itt tells us about how fast the plate is moving AND about the orientation of the Earth’s magnetic field.

Magnetic Field? What the shit?

The Earth’s magnetic field undergoes reversals every now-and-again. The reversals are far from periodic and lots of people worry about why and how they reverse in the first place. Sea floor rocks like basalt are created at the ridge axis. Basalt has a lot of iron in it (see "Rocks for Jocks"). When the hot magma hits the cold water, little bits of iron minerals align themselves in the orientation of the Earth’s magnetic field (like a teeny-weeny compasses). By investigating the orientation of those compasses we can learn when the reversals happened and how long they lasted.

I wish I could say that a magnetic reversal means something exciting will happen like fish turn into cheeseburgers or the sky turns pink, but aside from messing with a few birds nothing really crazy happens. Sorry, gang.

The Coriolis effect does not affect your toilet.

2007-04-30T10:24:00.000-07:00

Take a good look at your planet.

Purdy, ain’t she? So blue. And green. And yellow. And green and yellow in such organized bands across the globe. Start from the equator and look northward. Green, then yellow, then green again. Start from the equator and look southward. Green, then yellow, then green again. Why so organized? I'll tell you, homes, it's all about atmospheric circulation!

We live on a spherical planet and as such the most bulgy part of the world gets the most heat. Air at the equator is warmed up by solar energy and starts to rise. Convection takes over at this point and that warm air travels poleward while cooler air at the poles descends towards the equator. Simple enough, but not only is our planet spherical it rotates as well. The rotation of our planet sets in motion a very sneaky character that we now have to consider – the Coriolis effect.

Sorry to be a party pooper but no, your toilet is not affected by Coriolis. The system of fluid mechanics that is in your toilet is much too small to be influenced by the spinning of a gargantuan planet. What it does do is influence movement of stuff on the LARGE scale. I’m talkin’ ocean circulation, atmospheric circulation, intercontinental ballistic missiles, and the like.

As our warm air at the equator rises it looses the capability to hold moisture (see “Mommy, why does it rain?”). That’s why the tropics are so rainy. That air rises, dumps out all its moisture, then heads north or south. On its way it gets deflected by the Coriolis effect. The Coriolis effect deflects things to the right in the Northern Hemisphere and to the left in the Southern Hemisphere. You have to be careful with this deflection business because you’ve gotta think about it in the perspective of the air itself. Think of yourself moving along with the air. You’ll always veer right in the Northern Hemisphere and veer left in the Southern Hemisphere. A little hippy-dippy but the visualization helps in the long run.

At 30º N and 30º S the air hits a region of high pressure due to the “piling up” of more air that hasn’t moved its big butts outta the way on the journey towards the pole. The air starts to fall. It doesn’t have any moisture in it anymore so 30º N and 30º S get blasted with hot, dry air. This is why the world’s great deserts live at these latitudes. When the descending air gets lower in the atmosphere, some of it moves pole ward but some of it heads back towards the equator, creating the Trade Winds. The Trade Winds blow from East to West and in olden days came in handy for things like, yep you guessed it, trading! Hey, they were sailors, not wordsmiths.
The air that keeps heading for the poles gets deflected from the West to the East, so we get the Westerlies between 30ºN and 60º N (and 30º S and 60º S). Around 60º N and 60º S our pole ward traveling air has been sufficiently warmed enough and rises again, giving us a bit of rain at these latitudes. We see on the figure above that the Horse Latitudes and Doldrums are spots you don’t want to get stuck in with a sailboat because there's no wind. They’re called the Horse Latitudes because if you got stuck with your ship in these spots and you’ve gotta lighten your load to get moving, overboard go the horsies! I’m not kidding.
In this way, we develop the 3 atmospheric circulation cells.
* Equator to 30º = Hadley cell.
* 30º to 60º = Ferrell cell.
* 60º to Pole = polar cell.

I’ve drawn the above diagram more times than I care to remember. I drew it for the first time in my Intro to Oceanography class and I know I drew it at least once this semester. It is one of the few diagrams that has a special place in my heart, which is kinda pathetic but true none-the-less.

Figure citations.
http://nssdc.gsfc.nasa.gov/planetary/image/earth_day.jpg
http://www.sbg.ac.at/ipk/avstudio/pierofun/atmo/el-scans/hadley.jpg
http://weather.cod.edu/notes/circulation.gif

Rocks for Jocks

2007-04-23T13:22:00.000-07:00

Let's back it on up today and cover some basic info that you might be missing from your Science diet: Rocks. Don’t roll your eyes and say “boooorrring”, rocks are great. They tell very interesting…oh, who am I kidding. They ARE fucking boring, but I have to know about them none-the-less. My heart belongs to the sea so I’ve never found rocks to be particularly compelling. Some people do though. Those people are called petrologists and can be identified by their penchant for carrying around magnifying glasses and hammers. They are freaks for rocks but can be very informative and quite charming, especially on long car rides. They’ll tell you all about that road cut, or those hills in the background, or a particular metamorphic outcrop. My advice to you is to not let them drive unless you want to know more than you intended to know about the sedimentary layering of a ditch on the side of the road.

The thing about rocks is that there is a lot of nomenclature, lots of vocabulary to learn. Rocks "are aggregates of minerals" as the official definition goes. There are three categories for rocks: Igneous, Sedimentary, and Metamorphic.

Igneous: These rocks are the freshest of the bunch. They’re either made volcanically at the surface (EXTRUSIVE) or by the cooling of magma beneath the earths surface (INTRUSIVE). Rocks look A LOT different if they cool at the surface or cool inside the earth. Cooling inside the earth gives the rock time to develop big, purdy crystals. If you’re an igneous rock being fired out of a volcano, you don’t have much time to cool off before solidifying so your crystals are going to be itty-bitty.

Within the realm of igneous rocks, we’ve got the stuff that makes up our continental crust and the stuff that makes up our oceanic crust. The two look very very different. Oceanic crust is MAFIC which means it’s really rich in iron and so it’s black. Our favorite mafic rocks are Basalt and Gabbro. Continental crust is FELSIC and made up of lighter stuff like potassium, sodium, and silicon. Rocks with potassium are very cute and pink, so you’ll get a lot of white and pink in rocks like Granite and Rhyolite.

Sedimentary: sed. rox are made from the eroded bits and pieces of other rocks. They are made when sediments cement themselves together and are squeezed enough to form a new rock. They are identified by the size of the sediments that make them up. We’ve got fine grained stuff like Shale and Siltstone, moving into medium/sand sized stuff like Sandstone, and then to rocks that have big ole’ chunks in them like Breccia and Conglomerate. In the category of Sedimentary rocks are also evaporites like Halite (rock salt) and Gypsum (shit you use to make wall board).

Metamorphic: These rocks were igneous or sedimentary rocks at one time, but have been mooshed or buried long enough to metamorphose into a new kind of rock. We’ve got stuff like Gneiss, with it’s nice layering (that’s a geology joke for those who didn’t get it [fucking kill me now]). Gneiss can begin its life as Granite or a layered sedimentary rock. We’ve also got Slate, the stuff that chalkboards were once made out of. Slate is very black and very well layered. You squeeze the shit out of Slate and you’ll eventually get Schist – the rock responsible for the destruction of the St. Francis Dam (see “Damn Dam”). Let’s see, what else. Marble is a metamorphic rock, so that’s nice. No not Gneiss, nice. Awww, Gawd. I’m boring myself so I must be boring you. But now you know about rocks so, I guess that’s good?

Damn Dam

2007-04-16T10:02:00.000-07:00

Dam failures are bad. Really bad. Really really bad. As a society, we depend on our engineers to do the dirty work for us so we don’t have to think about all the hazards around us. And believe you me, there are plenty of hazards to worry about.

The class I teach has been talking a lot about the St. Francis dam lately. It was a dam built in the 20s by our friend William Mulholland. Two years after its completion, the dam failed and sent a wall of water roaring thru Santa Clarita and on out to the Pacific Ocean. It is the 2nd greatest loss of life in California, the 1st being the 1906 San Francisco earthquake. The tragedy killed at least 600 people (which is not insignificant considering the population of the area at the time) and ruined the career of our buddy Billy M.

After completing his first engineering masterpiece, the LA Aqueduct, Mulholland set his sights on water storage rather than water transport. He wanted to construct a reservoir of fresh water that LA could tap into incase something happened with the Aqueduct system. After the 1906 earthquake, geologists traced the San Andreas down to the vicinity of LA and Mulholland knew that his aqueduct snaked over the fault a couple times. It didn’t help that farmers were sabotaging the LA Aqueduct because of the royal screwing over they had received when water was diverted from the Owens Valley. He took all these factors into consideration and decided that it would be best to have a reservoir that could meet LA’s water needs for as long as necessary to get the water flowing again. A reservoir would need a dam.Above is a colorized picture of the St. Francis dam as it was. It's ok for that water to be comming out the middle. That part of the dam is called a spillway and allows water to be released from the reservoir when necessary. The 200ft gravity dam was completed in 1926 and promptly filled with water from the Aqueduct system. Everybody was happy, especially ole’ Mulholland.

The dam was leaky to begin with. Throughout 1926 and 1927, the damkeepers were forever noticing little spots of water seeping through the concrete. Mulholland justified these leaks by saying “Poppycock! (or whatever other 1920’s guffaw you can think of) That’s only natural. The concrete is settling as the reservoir is filling behind it, no big deal”.

Early in 1928, lots of people began tapping Mulholland on the shoulder saying “Ummm, there’s a lot of water leaking through your dam. Are you sure we shouldn’ be worried?” Under the advisement of the damkeeper, Tony Harnischfeger, Mulholland marched up to the dam for a personal inspection during the daylight hours of March 12, 1928. He walked on it, tapped it, probably kicked it a couple times, perhaps jumped up and down on it, and declared it safe. End of story. Stop calling me Harnischfeger he probably thought. What a pussy-ass damkeeper I’ve hired.
Even though it’s a confusing name, we should remember Tony Harnischfeger for being of sound mind. He was right to be worried because at 11:57pm that very same night, the dam busted wide open. A volume of water equal to three times the flow of the Mississippi roared down the canyon. It obliterated everything in its path. The map above shows the path the flood took. It followed along the Santa Clara River (see below) all the way to the ocean. Bodies were found as far south as San Diego and even Tijuana.

The cause of the break was not shotty engineering, but unsound geology. One side of the dam was built on an old landslide. The rocks on that side are schistose – schist being a metamorphic rock that has well defined layers. Under a sufficent load and with proper lubrication, this stuff sloughs off along the planes of the layering. The other side of the dam was built on a rock that disintegrates when wet. It seems solid enough when it’s dry, but saturate it with water and what was sturdy rock crumbles to pieces.

This catastrophe left Mulholland a broken man. To his credit, he did take full responsibility for the dam failure. Subsequent trials and investigations acquitted him of any egregious wrong-doing. What WAS his fault was the poo-pooing of any advice given to him by geologists before building his dam. He died in 1935 at the age of 79.

So there you have it. The story of St. Francis dam. Heavy shit, huh? I'll spare you the "those who do not learn from the past are doomed to repeat it" banter. It's an incredibly interesting story and one that all Angelinos especially should know.

Citations:
* St. Francis Dam - J. David Rodgers and Kevin James. Department of Geological Engineering. University of Missouri - Rolla
* Santa Clara River - Matthew Trump

Know your Germaniums!

2007-04-13T11:27:00.000-07:00

I'm having a hard time thinking today so let's stick with a subject that I know backwards and forwards: Germanium Isotopes.

Joke’s on you! There’s hardly anything to know about germanium isotopes.

YET.

In addition to working on my Master’s Project with the silica and germanium in the North Pacific, I’m also partly working on a project to measure germanium isotopes. If you mention germanium isotopes to an Isotope Geochemist, take special note of the worried look in their eyes and congratulate yourself on stumping a very smart person. My advisor and I are pretty much developing the technique for measuring these little guys in seawater. Why, you ask? Why give a shit about an element with such a ridiculous name? Well, I’ll tell you.

Germanium is #32 on the periodic table of elements. It’s a metalloid meaning that its behavior exists somewhere between a metal and non-metal. The most abundant isotope of germanium is Ge74 with 32 protons, 32 neutrons. Other isotopes of interest are Ge70, Ge72, Ge73, and Ge74. There are also some weird radioactive species of germanium floating around, but I don’t worry much about those guys. These are the four isotopes that I measure when I use a mass spectrometer (which I don’t like using very much [see “Mass Spectrometry Blows”]).

We’ve talked a little bit before about fractionation. Isotopic fractionation means that something (evaporation, precipitation, biology, whatever) has fucked with the natural abundance of isotopes in your sample. In the case of oxygen, fractionation happens during evaporation and precipitation. The fatty Fatterton isotopes get left behind in the seawater during evaporation and they are the first to drop out of the clouds when it rains.

Biology does an amazing amount of fractionation. It’s a lot easier to move around light isotopes than it is to move around heavy isotopes. This might not seem like a big deal to you and me, I mean come on! What’s a few atomic mass units? But when you are a single celled critter, that shit adds up. Carbon, oxygen, sulfur, and iron are all things that biology needs, and since life is inherently lazy it will to the least amount of work to get what it wants.

Problems that arise when one attempts to measure germanium isotopes:

1.) The mass difference between the lightest (70) and heaviest (74) species of germanium is not much compared to the overall weight of germanium: 4 mass units out of 74, which is only about 5%.

2.) There isn’t much germanium in seawater. My advisor and I have developed a way to concentrate ~ 99% of the germanium in a 20L seawater sample into about 40 mL. If I told you how we do it, I’d have to kill you.

3.) You have to have a top of the line Mass Spectrometer. Expensive and fussy.

4.) You have to be able to convert your germanium concentrate to a gas and input the gas into the Bitchy Mass Spectrometer at a perfectly constant rate. Sounds easy, but this shit is sensitive. We’re talkin’ isotopes, people.

So that’s where we’re at. We’ve got our germanium concentrate. We’ve got friends with mass specs, we just need to fine tune the procedure a little bit and voila! Germanium Isotopes! The Big Butt here is “But will this information be useful?” I don’t know, probably not. Useful or not though, it's still uncharted isotope territory that should be explored by someone and that someone is me!

Dishonorable Discharge

2007-04-11T10:05:00.000-07:00

The class I teach is learning all about rivers, floods, and groundwater this week. This subject is important to learn about, especially for folks living in Los Angeles. I don’t know if you’ve ever noticed, but it doesn’t exactly rain all that much in LA, which is good because people turn into Road Retards as soon as the pavement is wet. But it’s also bad in that we have a population of 14 million that is sustained on imported water.

As anybody who has seen Chinatown should know, Angelinos are big, fat, greedy water thieves. Back in early part of the century the LADWP and specifically chief engineer William Mulholland planned a fantastically devious way to reroute water from up north in order to provide water to the booming population in LA. People affiliated with the DWP started buying up land in the area of Owens Valley (see map) and before you know it, the LADWP owned a shit-load of land with precious precious water on it.

^ Area of Water Stealing ^

There are now two aqueducts that pilfer water from up North. The original built in 1913 runs about 220 miles and the other, completed in 1970 runs 137 miles.

^ Crazy-ass Aqueducts ^

You gotta hand it to Mulholland for being ballsy enough to make this insane plan a reality. Had I grown up in or around OwensValley AND been subjected to the vast wind storms created by the drying of the lake bed AND thereby developed severe respiratory problems because of all the particulates in the air AND had my family’s farm get fucked out of their water rights, then I would absolutely despise the man and probably all Angelinos. OwensValley is now as dry as a bone. Recently Mayor Villaraigosa made a big to-doo about rerouting water back into the OwensValley. You can read all about it here:

http://www.npr.org/templates/story/story.php?storyId=6590362.

As most things Mayors do, this flashy production is merely a matter of publicity and won’t really do much to restore OwensValley to what it was at the turn of the century.

But our story gets better! Not only do we jack water from Northern California, we also reroute water from the Colorado River (see below). LA gets about half its water from the LA Aqueduct system and about 40% from the Colorado River and State Water Project, um, projects. Only about 10% of the water we use comes from groundwater and surface runoff.

By rerouting water for our own consumption, we’ve now fucked over Baja Mexico for their part of the Colorado River. Where there used to be lush estuaries and wetlands are now desiccant.

Fascinating stuff, huh? Who knew that water could be so scandalous.

So the next time you are taking a shower or drinking a cool glass from the tap (god forbid!) or participating in a wet tee-shirt contest, be mindful of where your water has come from. It has been on a long an arduous journey and deserves your respect.

Figure references:
CO Aqueduct: (Colorado River Aqueduct © 2004 Matthew Trump
LA Aqueduct: http://www.ladwp.com/ladwp/cms/ladwp004409.jsp
OwensValley: Owens Valley © 2004 Matthew Trump

Mass Spectrometry blows

2007-04-09T10:26:00.000-07:00

Mass Spectrometers are big, expensive machines that rarely work properly. I have yet to encounter an Isotope Geochemist who likes working with them. If you own a mass spectrometer, chances are good that you spend the bulk of your budget getting the damn thing fixed only to have it poop out on you at a critical time. They’re fussy bitches. For instance, one that we have here at USC requires that you NOT walk around it as it is measuring for fear of screwing up the sample intake. It’s like a $750,000 baby.

So how do these stupid pieces of crap work? Well, I’ll do the best I can to explain the principles of Mass Spectrometry. Some of it will be hand-wavy because I’m not so keen on it myself, but you’ll get the gist. As always, we’ll begin at the beginning and explain the principles that make this instrument necessary.

Think back to the 4th grade when you learned about the atom. The basic components of an atom are protons, neutrons, and electrons. We define an element by its number of protons, but elements can and do have isotopes. An isotope is an atom with the same number of protons, but a different number of neutrons. For example: we’ve got Hydrogen (number 1 on the periodic table of the elements) which has two isotopes – Deuterium and Tritium. The most abundant of the three is plain, ole’ Hydrogen with one proton and one electron. Just an itty-bitty bit of all the Hydrogen we know and love is Deuterium (about 0.002%). Deuterium has one proton, one neutron, and one electron. Tritium has one proton and two neutrons and is radioactive with a half live of about 12 years.

Atoms can have LOTS of isotopes. Most of them are extremely unstable and only exist in the lab. Below is the famous “Chart of the Nuclides”. You’ve got the number of neutrons on the x-axis and the number of protons on the y-axis. The blue line is showing you a one-to-one relationship (protons = neutrons). You can see that the cluster of stable isotopes falls below this line. That’s because it’s really really hard for heavy atoms to be stable. Once you start pilling on the neutrons, you’re atom wants to break apart.

Since isotopes of the same element have a different number of neutrons, they have different masses. A Mass Spectrometer will let you separate out your isotopes according to those mass differences. Why all the bother, you ask? See “Science Lesson #2: Wally Broeker” for more info on why you would want to know the isotopic composition of something in the first place. Little critters tend to take up the lighter isotope of an element first, be it Sulfur, Carbon, Iron, Oxygen, Silica, etc. This is called fractionation. It’s only by looking at the isotopes of something (like sediments, or pyrite, or shells, or seawater) that you’ll see how much fractionation has been going on. From there you can infer what the biology has been up to.

To illustrate what a Mass Spectrometer actually does, imagine yourself running on a track. Or walking (lazy-pants!). You and a friend are walking along with you on the inside of the track and your friend on the outside. The track is an oval, so once you two reach the turn your friend has to walk faster to keep up with you. If she doesn’t walk faster she'll fall behind because you are a mean friend and won’t wait for her. In principle, this is what happens in a Mass Spectrometer.

Looking at the picture above, our atoms start out all together in the front part of the Mass Spectrometer (1). Let’s skip describing this part because the front end of our Mass Spec can get complicated depending on what kind of instrument you’re using. Our isotopes are spit out and head down what’s called a “Flight Tube” (2). At this point, a big magnet built into the Mass Spec pushes our isotopes around depending on their weight. This has nothing to do with the charge on the atom because our atoms have been stripped of their electrons (ionized). The heavier isotopes are going to take a different trajectory than our lighter isotopes (3). Little detector “cups” record how many atoms came down that path (4). At the end, you know how many isotopes came into each cup and from there you can calculate the abundancies of each isotope in your sample.

So there you have it: the principles behind Mass Spectrometry. A simple premises that is gummed up by complicated machinery. If I was smart I’d quit this grad student shit and get a job as a Mass Spec mechanic because as long as their will be Mass Specs, there will be broken Mass Specs.

Trig? Oh NO! Metry.

2007-04-06T09:40:00.000-07:00

Let's learn some Math today.

You’re thinking: Boooo! Math blows! Show me your tits!

I’ll admit that most of Math is tedious and frustrating, but some subjects within the realm of Math can actually be useful. Like Trigonometry.

I didn’t appreciate Trigonometry when I was learning it, but looking back on it now I have very fond memories of my days in Trig class. My friendship with Sine and Cosine and Tangent has stood…uuuhh, standed? withstood (?) the test of time. I remember this one time that Cosine got so black-out drunk and threw up in my car! I’ll warn you, folks, do NOT give that function Tequila. Good times.

This might be a stroll down memory lane for some of you, and for others it may seem like I’m taking you down a poorly lit back ally where you are going to get stabbed for your shoes. Don’t worry. If anyone stabs you and steals your shoes it’s going to be me. You have nothing to fear from Math. In fact, Math might help you in this situation because god knows I’ll turn on you at the drop of a hat.

We’ll begin by looking at our friend, the triangle. A right triangle always has one 90º angle and two acute angles (angles less than 90º). Right triangles are where we get all of our Trigonometric constituents from, like sine, cosine, and tangent. Other types of triangles are:

Equilateral: all angles equal 60 º, all sides the same length
Isosceles: two sides are the same length, 2 angles are equal
Obtuse: one angle is bigger than 90º
Acute: all angles are smaller than 90º

Back to the right triangle. So we’ve got one angle of 90º (indicated by that boxy thingy in the corner) and two others that are less than 90º. Let’s define one of those angles as theta (the “O” looking thing with the line through the middle). Let’s also give each side a name: Stalin, Churchill, and Roosevelt. You get to brush up on your history today too! sin θ = opposite / hypotenuse = Churchill / Roosevelt
cosin θ = adjacent / hypotenuse = Stalin / Roosevelt
tangent θ = sin θ / cosin θ = opposite / adjacent = Churchill / Stalin

If we take these functions and flip around what’s on top (the numerator) and what’s on bottom (the denominator) we can define 3 more functions: secant, cosecant and cotangent

secant θ = upside-down cosine = hypotenuse / adjacent = Roosevelt / Stalin
cosecant θ = upside-down sine = Roosevelt / Churchill
cotangent θ = upside-down tangent = Stalin / Roosevelt

From here, Trigonometry takes the ball and runs with it. You get into identities, Pythagorean theorems, Reduction Formulas, Double-Angle Formulas, Power-Reducing Formulas, and so much more. It’s hard to appreciate that such a vast subject can be built on such simple principles. Drink it in folks, it's a profound concept. Trigonometry is my friend, and it can be your friend too!

Mommy, why does it rain?

2007-04-04T13:52:00.000-07:00

Good Question. Why does it rain? The answer isn’t obvious. Let’s talk a little bit about the fabulousness of water vapor.

It’s a stone cold fact that warmer air can hold more water than cooler air. Hence, the favorite complaint of Bingo loving, cookie baking, grandmothers everywhere “It’s not the heat, it’s the humidity!” The relationship between water vapor content (which can be quantified via vapor pressure) and temperature looks like this:

It’s not linear, it's exponential. Air with properties above the line are called “supersaturated”. Air with properties below the line are called “undersaturated”. This can lead to something interesting when you mix them. Say you’ve got two parcels of air with different properties. One parcel, A, has a lower temperature and water vapor content and the other parcel, B, is warmer and has a higher water vapor content. (see below) Now bring those parcels into contact, they mix and the mixing line looks like this:
Uh oh! Our mixing line lives in the supersaturated zone, so put your galoshes on because you’re getting rained on, buddy.

Another reason why we get rain is because air cools as it rises. When it cools it’s less capable of holding moisture so all the water gets dumped out. This happens in places with topographic highs like mountains. You’ll always have a rainy side of your mountain and a dry side because of this very mechanism.

Keeping with today’s theme of simple questions with not-so-simple answers: why does air cool when it rises? Let’s back up and think about US, as humans, scurrying around on the surface of our plant. We don’t think about it much, but we’re under a lot of pressure because of all that gas in the atmosphere on top of us. Gas does have mass (rhyme!), and when you’ve got miles and miles of it piled up from the Earth’s surface out into the far reaches of space, it can add some serious poundage to your daily life. Right now you are being subjected to 14.7 pounds per square inch of atmospheric pressure. Right. Now. And. Now. Still Now. It’s always there, homes. Nothing you can do about it.

Gas, however, can do something about it. As gas moves up into the atmosphere, it moves into regions of lower pressure. It can relax finally, and stretch out. It expands and when it does that it cools.

Maybe the opposite case will cement this idea in your mind: when you pump up your bike tire, what happens? The tire warms up a little because you are compressing the air inside it. This process is called adiabatic heating or cooling. Whenever a gas expands, it cools. Whenever it compresses, it warms up.

So the next time some asshole tells you that it’s raining because God is crying, tell him about vapor pressure, mixing lines, and adiabatic cooling. If this angers and confuses your Redneck friend, just follow whatever you say with “America Rules!” and you’ll be safe.

Die, Die, Diatoms My Darling

2007-04-02T09:46:00.000-07:00

I have this fantasy that biologists and geologists all actually hate one another. This is so NOT the case, but wouldn’t it be hilarious if there was this deep-seeded hatred amongst the two science tribes? We could have knife fights á la “Beat It”, but instead of knifes it would be broken Erlenmeyer flasks. We could sabotage each others experiments. “DNA sequencing? How about ‘Bunsen Burner explosion in the face!’” Take that, nerd.

However funny this may be, I have to do some biology for my work as an oceanographer. The bulk of ocean chemistry depends on what is going on in the biological realm, so I have to keep track of a few species of sea-faring critters. The three I am most familiar with are Diatoms, Coccolithophores, and Forams. Today we’ll look at the wonderful world of the Diatom.

Diatoms are the guys I like the best because they are the main players in the Silica cycle. They are phytoplankton (plants) that have a siliceous shell encasing them called a frustule or test. The ones I deal with live in the photic zone, which tends to be the upper 100m of water depending on how murky your water is. Diatoms can grow CRAZY fast. The majority of the time they multiply vegetativly meaning that one diatom will break into two smaller diatoms. Individuals have the ability to make a new shell in 10-20 minutes! They’re big fans of regions with high nutrients like upwelling zones and the Southern Ocean. Wherever and whenever there is a high concentration of nutrients in the water, diatoms will hit hard and fast. They’ll zoom in and use up all the nutrients, creating what is referred to as a “bloom”, and then die off quickly when the nutrient supply has been drained.

It’s not totally obvious why a plant would want to grow a siliceous frustule. There are a few theories to explain why this might happen:

1.) To serve as a UV filter. UV light is super bad for you when you are a tiny phytoplankton.
2.) To act as armor to protect them from other critters that graze on them (this is probably the most likely explanation).
3.) To act as ballast so they can float up and down in the water column.
4.) Because they want to, motherfucker.

The majority (70-80%) of the silica that diatoms take up to make their frustules gets recycled in the surface waters. Some of it makes its way down into the seafloor where it gets deposited. People like me go out and collect seafloor sediments in interesting locations in order to find out how much silica has made it to the seafloor and what (if any) implications that may have to the water chemistry in the region.

Diatoms are one of the few living creatures that are ok in my book. Make a diatom YOUR friend today!

References:
http://www.reef.edu.au/asp_pages/secb.asp?FormNo=7
Douglas (2006) Biogenic Sediments: Carbonate and Silica
Photo credit: Dr. Neil Sullivan, University of Southern Calif.

Malibu (Iso)STASY

2007-03-30T14:00:00.000-07:00

Isostasy is a fun word to say. Isooostaaasy. Isotasy. Isostasy. Try it, you’ll like it.

Isostasy is a fancy word for something we are all familiar with. It is the kissing cousin of buoyancy. It is invoked to explain how we get so many different elevations around the globe.

Think of an iceberg. We all know that what we see above the water is a small percent of the total volume of ice. Let’s say we see 25% of the iceberg above the water. What happens as that iceberg melts? You loose ice, yes. The iceberg gets smaller, yes. But do you see any more than 25% of the iceberg above the water? No. You maintain the ratio of what is above the water to what is below the water even though the total volume of ice is less.

Now take this iceberg analogy and apply it to the Lithosphere.

SIDE NOTE! We talked the other day about what’s going on inside the Earth (see: The tale of Alfred Wegener) and defined the Core, Mantle, and Crust. I should clarify that the difference between what is considered “Crust” and what is considered “Mantle” is a compositional difference. When you hear “Lithosphere” and “Asthenosphere” you are now distinguishing between a phase difference. Lithosphere is solid, Asthenosphere is viscous. You can have chunks of Mantle rocks in the Lithosphere, just as long as those chunks are solid. Everybody cool? Ok, moving on…

Say a mountain is our iceberg. A solid hunk floating around in the viscous Asthenosphere. We can make this mountain smaller by erosion. Erosion breaks down the rocks that comprise our mountain and carries the sediment away via streams, rivers, or wind. Our mountain getting smaller is kinda like our iceberg melting. Just like the iceberg, as our mountain gets smaller, we maintain the ratio of exposed crust to the “root” below it. This can work in the opposite fashion. Say we have a convergent plate boundary where two continental plates are colliding (like the Himalayas) and neither plate wants to subduct beneath the other. The crust has nowhere to go but up. This is how we end up with the tallest mountains in the world. But now you know from the principles of isostasy, those big-ass mountains are supported by a HUGE-ass root underneath. That’s a lot of rocks, folks!

Isostasy can lead to something interesting which is called Isostatic Rebound. Imagine that you are the continental crust during a glacial. You’re grumpy because big, heavy ice sheets have collected on top of you. You are a little depressed and kinda cold. That’s a lot of fucking ice on your back, but wait! Here comes an interglacial. Ahhh, finally. The ice is melting. All that weight is lifted. You stretch out, you bounce back. The continental crust rebounds when all that ice goes away. This happens in places like the Baltic Sea and around Hudson Bay. Scandinavia is uplifting as we speak because of this very process.

So that’s isostasy. Not the most exciting topic in the world, but important to understand none-the-less. The next time you’re in a pool, demonstrate Isostatic Rebound to your friends by holding a beach ball underwater and then letting go so that it pops them in the face. “Isostatic rebound theory, bitch!”

The tale of Alfred Wegener

2007-03-27T14:59:00.000-07:00

Earth scientists LOVE the story of Alfred Wegener (pronounced Ve-guh-ner) because it’s the ultimate lesson about brilliance and vindication.

About 4.5 billion years before Alfred was born, the Earth as we know it was still a glint in our Solar System’s eye. Planets like the Earth are formed by the collision and amalgamation of many, many pieces of debris floating around in space. Little bitty dust particles start sticking together, then baseball sized globs of rock and metal start sticking together, then chunks the size of cars, then buses, then tall buildings, and so on and so forth until you’ve got yourself a big-ass planet. What happens then is the metallic stuff that was on those billions of itty-bitty chunks wants to sink down, down, down into the center of your new planet. The densest stuff (like iron and other metals) coagulates in the middle and all the really light stuff like silicate rock floats up to the top.

As you can see from the picture above, we’ve got the metallic Core (inner = solid, outer = liquid iron), then the Mantle which behaves like a plastic in the sense that it does indeed flow, but it flows on the timescale of millions of years. Then up on top we’ve got the part of the Earth that we know and love, the Crust. Our Crust is solid, but it floats around on top of the gooey, convecting stuff below it.

The crust itself is broken up into pieces that we call plates (see above). There are 52 plates in all (1). They range in size from the petite Juan de Fuca plate off the coast of Washington State, to big-mother plates like the Pacific plate which encompasses most of the Pacific Ocean. These plates have been on the move since their very existence – crashing into one another, subducting beneath one another, rifting apart, coming back together, ditching each other for a younger and sexier plate, getting mad and storming off in a huff, cheating on one another with their best friends plate, and…well you get the point.

300 million years ago all the continents were in one gigantic uber-continent: PANGEA (2). But by 180 million years ago the party was over and all the continents started to move into their current positions.

Alfred Wegener took notice of something that seems obvious to most of us now: If you move everything back together, it looked like South America and Africa were totally getting’ it on!

Shame on you, Brazil, taking advantage of the Ivory Coast like that!

Alfred Wegener backed up his new theory of “Plate Tectonics” by pointing out the existence of the same fossils in South America and Southern Africa. He also supported his theory of continental drift by presenting evidence of glaciation found in parts of Africa that are now quite warm. He concluded that Africa must have been closer to the South Pole at some point.

The problem with Alfred’s work was that he didn’t have a mechanism that would explain why the continents would move around in the first place. He proposed a theory suggesting that the continents flung themselves apart via centrifugal force. His claim was that that the inertia of the Earth spinning around was enough to break everything apart and spread it out all over the world like smelly undies in the spin cycle.

As you can imagine, there was plenty of harrumphing and monocle clasping when he presented his ideas in 1912. Nobody bought it. He was scorned and several organizations went out of their way to discredit his work in a very grandiose way. He died at the age of 50, never to see his theory come to fruition.

After WW2, new fangled technology allowed scientists to get a glimpse at what was actually going on under all that fucking water in the oceans. What they saw gave Alfred’s theory of Plate Tectonics the backbone it needed to be widely accepted: sea floor spreading. A paradigm shift ensued and now EVERYBODY believes in plate tectonics, except creationists who are fools. It’s taught in high school, it’s in every Earth Science textbook, it’s on Wikipedia, it’s everywhere. So lets all give props to Alfred Wegener for being ballsy enough to lay it all on the line.

He was awesome.

References:
(1) Bird, P. (2003) An updated digital model of plate boundaries, Geochemistry Geophysics Geosystems, 4(3), 1027
(2) Anderson, D.L. (1990) Planet Earth, pp 65-76 in Beatty, J.K. and A. Chaikin, eds. The New Solar System, 3rd ed., Cambridge Press, Cambridge, 326 pp.

Everyone has their Faults

2007-03-23T11:52:00.001-07:00

Let's talk faults. There are 4 types of faults that exist in the entire world: Normal faults, Reverse faults, Strike-Slip faults and Oblique faults. Anyone that tells you otherwise is a liar, a fool, or someone who majored in humanities (both).

The first type of fault is called a Normal Fault. A little bit of history here: all the terminology that deals with fault structures came by way of English miners. England doesn’t see much seismic action now-a-days, but when these miners were digging around for coal n’ stuff, they saw lots of old fault traces in the walls of their suffocating mine shafts. The faults they typically saw looked like this:

Move your eyes from left to right. Follow the yellow layer along until it is broken by the fault. Where does that layer go? Up or down? If you said down, give yourself a gold star! The hunk of rock on the left side of the fault is called the Foot Wall, the right side of the fault (the part that moved down) is called the Hanging Wall. That’s because these poor-ass miners in England, standing in a hole directly on the fault, would hang their lamps above them. Hence, the Hanging Wall. The wall they would be standing on is called the Foot Wall because, you guessed it, their feet were on it! I’m aware that this is totally archaic nomenclature, but it’s the best anyone has come up with. If you have a better idea, please contact your local geologist. They will promptly ignore you because you are not a geologist and shouldn’t go around mucking with precedence. The next kind of fault is a Reverse fault (see above). These types of faults occur where the Earth’s crust is being mashed together. To help you visualize this, picture yourself at a Demolition Derby/Monster Truck rally. Two cars are gunning for one another and there is about to be a SICK collision. POW! They collide, but what happens? Usually one car will pop up over the other. That’s like a reverse fault. One block has to pop up over the other block as they are colliding together.

When this collision happens between two oceanic plates, or between an oceanic plate and a continental plate, we get a subduction zone. When it happens between two continental plates – like India and Eurasia, we get big-ass mountains, or OROGENIES as hoity-toity geologists like to call them.

The next kind of fault is called a Strike-Slip or Lateral fault. These faults have all their motion in the horizontal. Our favorite Strike-Slip fault is of course, the San Andreas Fault in western California. There is an analogous fault in Northern Turkey called the North Anatolian Fault. But we aren’t bombing Turkey right now, so who gives a shit what’s going on over there?!

The tricky part with strike-slip faults is determining whether they are a Right Lateral or Left Lateral. I’ll tell you how I do it:

1.) Look at your fault in map view, ie looking down on it from above.

2.) Draw two dots, one on either side of the fault. Imagine one dot is you and the other dot is a friend of yours. Wave hi to your buddy!3.) Now imagine that there is an earthquake. EARTHQUAKE, AHHH! Move your friend over a little bit according to the arrow of motion on his/her side of the fault 4.) From your perspective, your friend should have moved to the right. And from your friend’s perspective, you have moved to his/her right.
5.) You’ve got yourself a right-lateral fault, Chief!

The San Andreas Fault is a right-lateral fault. The Pacific plate is moving northwards at a rate of about 35 mm/yr. Attached to that plate is everything on the west of the red line you see on the map below. That means that in a few million years, Los Angeles will be within spitting distance of San Francisco. And spit we shall.

The last type of fault, an Oblique fault is just a combination of a Dip-Slip fault (either Reverse or Normal) and a Strike-Slip fault. A little bit of vertical motion. A little bit of horizontal motion.

Now you know all about faults! Good for you!

So here's the plan. Man.

2007-03-21T17:03:00.000-07:00

Sorry kids. No science lesson today. I'm thinking that what I'll do is post 3 or 4 science lessons per week. The days of the week that they come will be a surprise. Awww, don't be sad. I'd love to tell you about the wondrous world of science everyday! But I have papers to grade, classes to attend, excuses to make, and a thesis to ignore.

If it makes you feel better, I put my underwear on backwards this morning. And I still have them on backwards. For inquiring minds, they're boy-shorts so it's a simple mistake to make.

Hanes MY Way, bitch.

Science Lesson #4: MAGNITUDES!

2007-03-20T12:08:00.000-07:00

Like most things sciency, there is more to reporting an earthquake’s magnitude than meets the eye. When an earthquake happens, all you hear on the news is “Magnitude 6.7 on the Richter scale. Epicenter 2.3 miles from Buttfuck, California”. What you don’t hear is the squabbling between geophysics tribes about the earthquake’s Moment Magnitude, Duration Magnitude, Richter Magnitude, Body Wave Magnitude, and Surface Wave Magnitude. I shit you not: there are that many magnitude scales.

Let’s sort them out together. To make this easier to understand, I will compare each magnitude scale to an actress with the first name of Jessica.

Richter Magnitude = Jessica Lang: The stalwart scale we all know and love. Charles Richter and Beno Guttenberg were fancy-pants geophysicists at CalTech in the early part of the 20th century. Together they built a Wood-Anderson seismograph – a very specific kind of torsion seismograph. Reporting an earthquake’s magnitude on the Richter Scale means that you’ve recorded the earthquake on one of these special seismographs at exactly 100km (about 60 miles) from the earthquake.

The sucky part about a Wood-Anderson seismometer is that it can only record earthquakes up to about a 6.8. Bigger than that and the mechanisms inside go all screwy and you don’t get a good record of the event. You can make all kind of mathematical corrections, but it basically blows your seismogram off scale.

Note: SEISMOGRAPH = THE INSTRUMENT
SEISMOGRAM = THE PIECE OF PAPER WITH THE SQUIGGLES ON IT

Even though Richter magnitude may not be the hot young thing it once was, we all should give props to Chuck and Beno for deciding that magnitudes should be recorded on logarithmic scales. You see, graphically a log scale looks like this

So as numbers get bigger and bigger on the x-axis, they don’t get much bigger on the y-axis. This is great because you can describe an infinite range of magnitudes on a relatively small scale. Theoretically you could have an earthquake with a magnitude of 20 or 100 or infinity, but an earthquake that size would mean that the entire Earth had been torn into two pieces. If that happens I wouldn’t really care if it was a 20.1 or a 22.7, I would be worried about my head exploding a la “Total Recall” in the vacuum of space.

Duration Magnitude = Jessica Alba: Fails to deliver consistent results. This scale deals with how long an earthquake lasts. This can get you into trouble because the duration of an earthquake in any one location depends on what’s going on with the rocks you’re standing on. If you’re in a basin filled with sand (I’m looking at you, Los Angeles) the earthquake is gonna last a lot longer than if you are standing on good, solid bedrock.

Moment Magnitude = Jessica Biel: These days this is the popular magnitude scale. The Moment Magnitude scale relies on something called the seismic moment of an earthquake which incorporates the area of the fault that slipped and how much the fault was displaced. No special kind of seismograph, no instructions on where to record the earthquake. Just quantities that are physically measurable. Nice.

Body/Surface Wave Magnitude = Jessica Simpson: I'm gonna sweep these two scales under the rug for now. It's not that they aren't useful, but they entail some explanation of how earthquake waves travel through the earth. You can live without them.

Science Lesson #3: Fun with Acronyms!

2007-03-19T13:46:00.000-07:00

In my years as a budding young scientist, I've encountered innumerable acronyms. Some of them are useful, most of them aren't. I thought I'd share them with you in the event that you yourself encounter a few someday. Who knows, maybe you'll win $20 from your grandma in the event that there is a Jeopardy category with a few of these bad-boys slipped in there. Or say you're kidnapped, bound and gagged and your kidnappers leave a bottle marked BTEX within reach. From this list, you know that BTEX are chemicals in gasoline and gasoline is flammable, so while they're gone to buy sandwiches you kick it over. The next time one of your kidnappers flicks the cigarette he just burned you with onto the ground, BOOM! Jokes on them 'cause you just bought yourself a quick and ideally painless death. Won't you be glad that someone told you what BTEX means when you're sipping margaritas poolside with the big G in Heaven.

SST: Sea Surface Temperature
DO: Dissolved Oxygen
ACC: Antarctic Circumpolar Current
PF: Polar Front
SAF: Sub-Antarctic Front
IGPP: Institute for Geophysics and Planetary Physics
REDOX: Reduction and oxidation
LGM: Last Glacial Maximum
CTD: Conductivity, Temperature and Depth
CCD: Carbonate Compensation Depth
THC: Thermohaline Circulation (not the drug)
OAE: Ocean Anoxia Event
OMZ: Oxygen Minimum Zone
BTEX: Benzene, Toluene, Ethylbenzene, Xylene (chemicals in gasoline)
MCL: Maximum Contamination Level
MCLG: Maximum Contamination Local Goal
HSRAAFAYC: Holy Shit, Run Away As Fast As You Can!
DNAPLS: Dense Non-Aqueous Phase Liquids
LDNAPLS: Low Density Non-Aqueous Phase Liquids
ODP: Ocean Drilling Project
VSMOW: Vienna Standard Mean Ocean Water
PDB: Pee Dee Belemnite
DIC: Dissolved Inorganic Carbon
TCO2: Total CO2
CDT: Canyon Diablo Troilite
DON: Dissolved Organic Nitrogen
ANAMMOX: Anaerobic Ammonium Oxidation (thanks, Mike)
NADW: North Atlantic Deep Water
PPM: Parts Per Million
PPB: Parts Per Billion
PPT: Precipitation or Parts Per Trillion
K/T: Cretaceous-Tertiary Boundary (when all the dinosaurs died)
EPICA: European Project for Ice Coring in Antarctica
LGS: Late Glacial Stage
ENSO: El Nino, Southern Oscillation
PDO: Pacific Decadal Oscillation
DO events: Dansgaard-Oeschger Events (rapid global warming events)
PAGES: Past Global Changes (shouldn’t this be PGC?)
PEP II: Polar Equator-Pole Program
PEEPOLE: I Wish This Was An Acronym
BP: Before Present (actually, before 1950. it's a long story)
MOR: Mid-Ocean Ridge
EPR: East Pacific Rise
SAF: San Andreas Fault

I'm Walkin' On Sunshine!

2007-03-09T10:31:00.000-08:00

Here are notes from my Paleoceanography class. It's mostly boring and the teacher is a lunatic. We talk about the same stuff over and over and over ever time we meet. I had "Walkin' on Sunshine" stuck in my head. The boat is the RV Thomspon - the research vessel I do my work on.

Here's your stapler, Little Girl

2007-03-08T13:48:00.000-08:00

You wouldn’t guess it if you knew me now, but I was fucking nuts for stuft animals when I was a kid. I wasn’t allowed a dog until the 3rd grade, so I made due with fuzzy and squishy creatures purchased from Toys R Us. There were bunnies, bears, dogs, cats, frogs, whales, sea otters, monsters, snakes, monkeys, giraffes, koala bears, probably an armadillo, mice, squirrels, pigs, peacocks and anything else you can turn into a fluffy friend. What there were NOT were dolls. I was never interested in human-themed playthings. Kens and Barbies were only shifty-eyed zookeepers that would breeze in and out of the elaborate productions I would choreograph starring Mr. Chetsworth, the gorilla, and Mrs. Ellington, the penguin.

I had one huge bunny when I was real little, like maybe 3 or 4. It was yellow with big eyes and the typical bucktooth bunny smile. I’d drag it around until it was filthy, then it’d get washed and fluffed and the vicious cycle of dragging would continue. The bunny is even in a picture of me taken WITH a person in a bunny suit while I’m in my Easter dress. I look worried. “Too. Many. Bunnies.” I’m thinking. I was practically a baby, it was confusing.

The only reason I remember the bunny is because it met its demise when I caught a really bad flu and threw up all over it. This was very sad because it was the only stuft animal I had that was bigger than me. I’d come close to experiencing such enchantment only one other time in my life.

When I was 7 years old, my elementary school had a raffle at the obligatory “Bi-Annual-Yes-We-All-Have-Parents” barbeque. Raffle prizes were of the typical fare: school supplies, a couple tee-shirts, trapper keepers, gift certificates, and so on. These things were of little interest to me, but behind the table displaying the various sundries that you could win was the most perfect 4-foot stuft polar bear you could possibly imagine. Beautifully clean and white, with big black beads for eyes, and a little red heart between its paws that read “You are berry special!”. It was huge. I had to have it. I just knew I would win it! Jesus, let me win that! Come on dude, be on my side for once. I promise I’ll do everything right from now on, just let me win that giant bear!

I bought raffle tickets. Not too many as I recall, but I was convinced that any one of them was a winner. I was so confident that that bear would be mine, I could just see it looming over all the other animals, smiling at me. I AM berry special, thank you for noticing! He would be named William. William the Polar Bear.

Raffle time comes. Crappy prizes given out. I wasn’t really paying attention, I was thinking about how awesome it will be driving home in my parents Caravan with that bear sitting next to me. Buckle up, William! What’s that, you’re hungry? We’re almost home, I’ll make you mini pizzas when we get back to YOUR new house. You’re rad, William!

Bear, bear, bear, bear. Numbers calling. Look through tickets. No, not that. No, not that one either. Not you. Or you. Or you. Or…

Any of these.

But, no. That’s my bear. William? What’s going on? How could you go with someone else? How could this happen?

I wandered up to the table and showed them my tickets. Surely this was a mistake, ha ha! You see, you didn’t call the numbers on my tickets when giving out that bear! So how about I just take the bear and we call it a day, hmmm? No. But.

Wait, what’s that? I DID win something? Oh my God, what is it? It’s a stapler? A STAPLER!? Is this a joke? No? Anybody? No joke. What a rip-off.

I only realize now that my life took a dramatic turn that night. I felt the chilly embrace of Disappointment for the first time. And she has been my companion ever since.

I'm Sory Matt Walsh

2007-02-26T14:13:00.000-08:00

This story is shameful and true.

I have a crush on H. Jon Benjamin. The voice of Ben Katz from Dr. Katz, John McGuirk from Home Movies and countless other hilarious animated roles. He’s the random medic in “Not Another Teen Movie”, and the crazy friend Keith in “Martin and Orloff”. There are no more than 6, no fewer than 3 men I would totally make out with in a heartbeat, and he’s numero uno. Don’t get me wrong, I’m not talking about dating or courtship or love any of that stupid crap. Just having some drinks, having some laughs peppered with a few awkward pauses, and then a heated make out session in the bar’s bathroom. I get to fulfill a weird fantasy of mine and he gets to make out with an awesome babe. Everyone wins.

Life keeps us apart however – he has a baby (and thusly a baby mama. drama. [oh, snap!]). I’ve got a great guy that will eventually be my baby daddy, and before you get all antsy in the pantsy, he’s got a list too. If Amy Sedaris walked up to him and said “Let’s make out.” I’d say “Touché Amy Sedaris. Have fun!”. Then I’d tell everyone that I totally made out with someone who made out with Amy Sedaris. We’ve both given each other clearance for making out, so long as it’s only making out. Make out = yes. Gentiles = no. Boobies = we’ll see.

Where Matt Walsh of Upright Citizens Brigade fame comes into this, is here: I was trying to find a copy of Martin and Orloff because of my afore mentioned crush on H. Jon Benjamin. I tried the Virgin Megastore AND Amoeba at Sunset and Vine, which says a lot since I never, ever, never, never, ever, ever, never go into Amoeba unless it is an emergency. This was an emergency. I have my reasons for disliking Amoeba and will discuss them some other time. The movie, sadly, was nowhere to be found. I had an idea. My idea was to go to the UCB theater on Franklin and buy it there. Why not support the very institution that fathered such a great movie? Brilliant!

When I got there the door was open, but nobody was around. At all. Even a little. Totally empty. I could hear voices in the way back, but that was at the end of a very long hallway and I assumed they were doing something back there, I didn’t want to interrupt. The movie was on the counter, H. Jon at last! But I only had a credit card to pay for it. All I had to do is wait for someone to come out and take my money. And so I waited. And waited. And waited. And waited. And…what the fuck? I wanted to do was pay for the movie and get out of there. The movie had dust on it for Christ sake, I’ll give it a good home where it will be watched compulsively. More waiting followed, I became desperate.

With a quick check of video cameras (Ha, who am I kidding, this is UCB!?) the movie was in my pants and I was out the door. I figured that any comedy team who has revealed a 4 foot phallus on Good Morning America couldn’t get too pissed about missing one copy of their movie. I told myself that they must have boxes and boxes of DVDs in some storeroom. Somebody will eventually notice that it’s gone, blame somebody else in the theater (it’s the freshman, those no good new people! I knew they were thieves!), go grab another copy from the storeroom, put it on the counter, and all will be forgotten.

This story has a happy ending – I have since given the movie a loving home. It has not been scratched or chipped, it has been watched diligently, studied, and appreciated. Laughed at all the appropriate times, revered at all the other times. I still feel bad about steeling it though. So Matt Walsh, if I ever meet you in person, I owe you $20. And for the love of God, either lock that door or put the boxes out with no disc in them. You actors are such suckers.

Science Lesson #1: Oceanograph-me

2007-02-23T13:20:00.000-08:00

A Masters Thesis entails a lot of work, a lot of work that I don’t want to do right now. It involves painstaking edits and re-edits, draft after draft, looking up and reading boring reference papers just so you can find one factoid to include in your introduction, and so on. It’s a painful and lengthy experience that I’m not looking forward to starting. But I have to start it, so what I’m going to do is take today’s post and make it about my work. You get to learn something new and I get to feel like I actually did something worthwhile.

I am marine geochemist, which is the same as saying I am a chemical oceanographer. There are a couple of things you should know about oceanographers before we begin:

1.) 99.9% of us do not work with whales, sharks, sting-rays, seals, octopi, or manatees
2.) If you meet someone who works with big, dumb sea creatures, chances are they are a trainer at Sea World and NOT an oceanographer.
3.) There are various forums for oceanography – biological, physical, and chemical.
4.) We are the only scientists allowed to be drunk at conferences (Well, not really. But chances are that if you see us at a conference, we are drunk anyway)
5.) Most oceanographers get sea-sick

That’s a few things to start us off with, there are many many more titillating things to know about oceanographers, but I’ll leave you to figure those out on your own.

I’ve been working on a project in the North Pacific with people at the University of Washington in Seattle. The North Pacific has an overabundance of silica, which is what little critters like diatoms make their shells out of. These diatoms live happy but short lives at the surface, then die, and then their shells fall into the deep sea. The silica either redissolves in the water column or gets deposited on the seafloor and makes what we call biogenic opal. The funny thing about the North Pacific is that the excess silica is neither at the surface nor at the seafloor. Excess silica at the surface would mean there are a shitload of diatoms and thus nutrients (and yes, shitload is a scientific term), whereas excess at the seafloor would mean there is a buttload of silica being deposited on the seafloor (scientific as well, thank you). The “plume” as we call it exists at midwater depth – 2300m. For my non-metric minded friends, 1 meter is about 3 feet.

So where is this silica coming from and why is it at this mysterious depth? That’s what I’m working on. I use another element called Germanium to determine if the silica is from the shells of little critters or if the silica is from places like hot vents. Germanium is the downstairs neighbor of silica on the periodic table of elements. When diatoms take up silica to make their shells, just a teeny-tiny bit of Germanium gets incorporated along with the silica. When those shells dissolve, they give back the silica and germanium to the water in a very specific ratio that tells chemical oceanographers like myself “Oooohhh, this silica is from a diatom!”.

If the silica is from hot vents, it is LOADED with germanium. A chemical oceanographer would measure the germanium and silica in the seawater and plot those values against one another on a graph – silica on the x-axis, germanium on the y-axis. If we get an almost horizontal line, we’ve got diatoms. If we get an almost vertical line, we’ve got hot vents.

See, easy-peesy! Now you know something you didn’t know before. Science is awesome.

Peek-a-boo!

2007-02-22T17:39:00.000-08:00

Oh My God, you found me!

For whatever reason I was forcebly removed from MySpace. I didn't have any pictures of my who-who or ta-ta either. MySpace is for sissies and perverts anyways.

But now that we're together again I will gladly entertain you with my thoughts on anything and everything. Stick with me, my darlings. You're in for a hell of a ride.

Love,
PK