Ice Stories: Dispatches From Polar Scientists » East Antarctica http://icestories.exploratorium.edu/dispatches Mon, 15 Nov 2010 20:40:36 +0000 http://wordpress.org/?v=2.9.2 en hourly 1 Wilkes Land Expedition http://icestories.exploratorium.edu/dispatches/antarctic-projects/wilkes-land-expedition/ http://icestories.exploratorium.edu/dispatches/antarctic-projects/wilkes-land-expedition/#comments Fri, 15 Jan 2010 18:36:10 +0000 Exploratorium http://icestories.exploratorium.edu/dispatches/?page_id=2143 Drilling into Antarctica’s Deep Climate Past


The JOIDES Resolution.

The JOIDES Resolution.

One of the most sudden and dramatic climate changes to impact the earth occurred some 30 million years ago: This was the transition from a Greenhouse World, when ice caps were largely absent and the earth was much warmer, to an Icehouse World with extensive polar ice sheets, exposed land along the continental margins, and glaciers that periodically extended into the lower latitudes. Investigating this climate switch, thought to be mediated by changes in atmospheric carbon dioxide concentration, will help scientists better understand what triggers vast environmental changes that fundamentally affect life on earth.

Ground zero in these studies is the area just off the coast of the East Antarctic Ice Sheet, the world’s oldest and largest polar ice field. By drilling into deep ocean sediments along Antarctica, scientists hope to uncover the earth’s climate history from a time when East Antarctica was largely ice-free, and to investigate its transition to the glacier-covered continent we know today. Investigating this history, and the effect of increased carbon dioxide and other greenhouse gases on polar ice sheets, will help fine-tune computer models and lead to a better understanding of the climate changes we’re experiencing in the present day.


An example of a cross-section of a sediment core.

Co-chief scientist Carlotta Escutia led an international team of marine geologists and climate scientists aboard the JOIDES Resolution, one of the most sophisticated ocean-drilling ships in the world. They set off from New Zealand in early 2010 to drill cores and collect sediment samples off the coast of Wilkes Land, a region of East Antarctica south of Australia that’s thought to have been the final area to become ice-covered during the last great climate transition.Marine geochemists Rob Dunbar and Christina Riesselman from Stanford University reported from this history-making expedition.


Planned drilling locations (yellow markers) for the IODP Wilkes Land Expedition.
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Meet Ole, Our Doctor http://icestories.exploratorium.edu/dispatches/meet-ole-our-doctor/ http://icestories.exploratorium.edu/dispatches/meet-ole-our-doctor/#comments Mon, 14 Sep 2009 19:04:04 +0000 Zoe Courville http://icestories.exploratorium.edu/dispatches/?p=1821 HANOVER, NEW HAMPSHIRE– Our traverse doctor, Ole Tveiten (I had a hard time getting the “ooo” right in Ole), luckily did not have much to do as a doctor, so he was put to work logging the cores, measuring and weighing them.



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The Train from Pole to Troll http://icestories.exploratorium.edu/dispatches/the-train-from-pole-to-troll/ http://icestories.exploratorium.edu/dispatches/the-train-from-pole-to-troll/#comments Wed, 25 Feb 2009 20:16:39 +0000 Mary Miller http://icestories.exploratorium.edu/dispatches/?p=1575 SOUTH POLE, ANTARCTICA– At the South Pole, we met up with Ice Stories correspondent Zoe Courville just before she and her team embarked on their 3,000 km traverse across the desolate and frigid East Antarctic Ice Sheet. In this video, Zoe gives us a tour of the vehicles they are taking on their cross-continent journey, including their living module, sleeping quarters, and science sled. (Video by Lisa Strong-Aufhauser.)



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Mapping East Antarctica’s Uncharted Territory http://icestories.exploratorium.edu/dispatches/mapping-east-antarcticas-uncharted-territory/ http://icestories.exploratorium.edu/dispatches/mapping-east-antarcticas-uncharted-territory/#comments Fri, 06 Feb 2009 18:55:10 +0000 Mary Miller http://icestories.exploratorium.edu/dispatches/?p=1545 WILLIAMS FIELD, NEAR MCMURDO STATION, ANTARCTICA– East Antarctica contains nearly all the world’s supply of fresh water and could contribute hundreds of feet of sea level rise, yet little is known about the stability of this vast ice sheet. In our interview with Jack Holt of the University of Texas at Austin, we learn about a project to chart a glacier in East Antarctica that scientists believe is losing mass. (Video by Lisa Strong-Aufhauser.)



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Out of AGAP http://icestories.exploratorium.edu/dispatches/out-of-agap/ http://icestories.exploratorium.edu/dispatches/out-of-agap/#comments Thu, 05 Feb 2009 01:39:55 +0000 Adrienne Block http://icestories.exploratorium.edu/dispatches/?p=1538 January 24th, 2009

MCMURDO STATION, ANTARCTICA– The problem with going to remote places is that no one wants to come pick you up. As of the 13th, we had a plan for finishing the survey, getting all the science personnel out of AGAP and leaving Antarctica on the HERC flight that left at 7am yesterday. Reality is: not a single member of the AGAP-South staff or science team was on that flight. Since the 13th we have been waiting for a ride out of East Antarctica, a ride that each day was promised and then taken away. The carps and electricians have it the worst. Their ride was supposed to come on the 13th, while the science team has just been waiting since the 15th or 16th. The funny thing is that the weather here was supposed to turn so foul and cold that we would not be able to get picked up at this time. It’s still a balmy -25F… normal AGAP summer temperatures.

Many of the HERC cancellations have had nothing to do with weather here at AGAP. The majority of flights were canceled because of mechanical problems and a few more were kept away by the forecast, not the actual weather. Last Tuesday, the HERC circled overhead and turned back to town without stopping. We later learned it had an engine failure that would prevent it from taking off again had it landed. That solace was not provided before the phrase “If a HERC circles twice and does not land, you’ve been AGAP’d” was added to the collection of poems, cultural arguments and witty limericks on the outhouse walls.

Yesterday morning, we were canceled again despite beautiful weather on the plateau. This particular HERC could not get appropriate air pressure in the passenger cabin. Normally, airplanes are kept at a pressure altitude of no more than 8000 ft, which is comfortable for most people when they are sitting or sleeping. Weather systems are often associated with pockets of high and low pressure. As they pass over, they change the pressure altitude or the amount of oxygen available in the air. Our science party has experienced pressure altitudes of near 16,000 ft while at AGAP. When they called to cancel the HERC because they couldn’t lower the altitude inside of it by pumping the plane full of oxygen, we all objected. Everything is downhill from AGAP! We are already at the maximum altitude we’d experience during flight and 2 days before we were 2,000 ft higher! Despite our exclamations, arguing with a HERC will never make it land. But later that night, a HERC finally landed! More importantly, it stopped, added 3,000 gallons of fuel to the AGAP fuel bladder and then hauled away with 20+ passengers and tons of cargo.


The much awaited HERC finally lands on the AGAP runway.

AGAP residents eagerly wait while cargo is loaded onto the HERC. Everyone was smiling and there was even some dancing… mostly because it was so cold.

Having waited patiently all weekend, Nick can’t hold back his excitement anymore.

Now back in McMurdo, the AGAP team will work to disassemble the science kit on the plane, pack, label and ship all our gear back to New York. Meanwhile, I am packing my personal things and coming to terms with going home — particularly since it will still be winter when I get there. A month in East Antarctica is plenty of winter for any year!

Not missing the cold of Antarctica does not save me from missing the adventure. As the reality of leaving this great continent dawned on me, I decided I had to throw myself in the deep end one more time: I took the polar plunge. Yes, I jumped into freezing cold, salty water in a cutaway in the ice shelf. It was surprising — like when we discovered one of the Recovery lakes is not a lake at all; it was cold, like the windy day on the plateau when the wind chill hit -55F and it was exhilarating — like all science fieldwork should be. What better way to end this journey of learning?


Swimming to the ladder after jumping into the Ross Sea as part of the annual Polar Plunge at Scott Base. Trust me — it’s not ideal bathing suit weather!
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Devil Snow http://icestories.exploratorium.edu/dispatches/devil-snow/ http://icestories.exploratorium.edu/dispatches/devil-snow/#comments Wed, 04 Feb 2009 19:18:05 +0000 Zoe Courville http://icestories.exploratorium.edu/dispatches/?p=1534 RECOVERY LAKES, ANTARCTICA– We’ve spent the last 3 weeks, the majority of our science days, in a region known as Recovery Lakes, or the Lake District as we affectionately call it. This system of several lakes, recently discovered, are subglacial– that is, they are below the 3000-some-odd meters of ice we are traveling over.

It is mind-boggling, I know, that there is unfrozen water that far below us, and under all that ice. The lakes are formed from heat from the earth being trapped and insulated by the several kilometers of ice and occur at the outflow of the Recovery Ice Stream, a large region of fast flowing ice.

One defining surface characteristic of the lakes is that they are flat, flat, flat, flat. There are no sastrugi [sharp frozen ridges and mounds in the snow], which we have become used to, or topography to speak of (not there was much before).

But while the landscape here is a bit monotonous, the snow here is really weird. Really weird. The top bit of snow is pretty new–some wind blown and some freshly fallen. It’s been snowing off and on while we were at camp, which is actually really rare for East Antarctica– we are in a polar desert after all. But the combined action of the wind packing the snow and changes induced by the ever-present cold temperatures and sun during the summer months have made for some of the hardest layers in the near surface I have ever encountered.

One layer, which Tom and I have been calling the MOAHL (or Mother of All Hard Layers), 1.2m deep in my pit, actually hurt my hands, shoulders and arms as I tried to dig into it with my shovel. It felt like I was trying to dig into pavement. Below the MOAHL, the snow is sugary and coarse and won’t stay together. This snow has frustrated nearly all our attempts to drill cores in it. We drill down, only to have the sugary stuff fall apart in the barrel. It’s been very exasperating– we’ve started and abandoned 10 different holes trying to get a core. I’ve started calling it Devil Snow.


Devil Snow crystals. Pretty to look at, but their rounded shapes make them not bond well to neighboring crystals, and hard to work with.

The Devil Snow is also hard to dig, falling apart on the shovel, raining down on your face and into your jacket—leaving you spitting out the coarse, sharp crystals and trying to scrape them out from your collar. It makes it hard to cut blocks out of it for the water melters, which we use for our drinking water as well. Devil Snow.

Despite the Devil Snow, we have managed to make some progress. I have dug another three pits, we have collected some shallow cores, and Lou collected one 90 m core and another 20 m core. We’ve installed a string of several temperature sensors for Ted Scambos’s graduate student Atsu in the deep hole. The temperature data is being sent via satellite to Atsu in Boulder at the University of Colorado, where he can monitor the data for changes. We already heard from him that he is receiving the data!


Lou with a monster piece of core from the Devil Snow area. The cores should be 1 m long to fit in the insulated core boxes we have, but Lou had problems getting the core out of the hole since the ice and snow is so soft. She had to keep drilling further to try to get something that she could grab onto.

Ted Scambos’s temperature string, powered with solar panels, beaming data back to Boulder.

Ted also installed a GPS station on the last of the lakes in order to track any changes in the level of the lake. This particular spot seemed to move up and down vertically in the last five years, as if there was a lake draining and refilling. Devil Snow or no Devil Snow, we are getting science done.

Speaking of Devil Snow, we’ve decided to start a heavy metal band called Monster Sastrugi, with the first single called Sastrugi Tongue. The other tracks on our album would be:
- Hot Raro (Raro is the New Zealand drink we have at every meal; it’s like Tang)
- Hand Core to the Transition Zone (this was Tom’s song from graduate school)
- Barrel Full of Chips (Ted thinks this song is too country-western)
- Do You Really Want to Drill Here?
- Devil Snow
- Little Cold Metal Parts
- Lost my Sprocket Wheel (luckily just once on this trip)
- Planetary Gears Rock
- Hot Differentials
- UFO Hunting in Antarctica

Of course we have, collectively, no musical talents, so there is no need to worry about the band ever producing any music– you can breathe a sigh of relief.

This brings me to another list we have been working on, the top 10 signs you’ve been on the Antarctic Plateau too long:
10. You are no longer fit for polite society.
9. Coffee consumption passes 5 cups for breakfast.
8. You expect things to go wrong.
7. -20 deg C is a “hot day.”
6. 3 meters doesn’t seem that far to dig.
5. Raro starts to taste good, and the colors are pretty.
4. When someone says they saw dragon-shaped sastrugi, someone else asks if they were Asian or fairy tale-type dragons (the answer was both).
3. You think that the piece of lint drifting across the snow is an insect, and that it would make a good pet.
2. The thought of a fresh apple makes you salivate.

And the number one sign that you’ve been on the Antarctic Plateau too long:
1. Everything is funny.

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Pits http://icestories.exploratorium.edu/dispatches/pits/ http://icestories.exploratorium.edu/dispatches/pits/#comments Tue, 03 Feb 2009 01:54:24 +0000 Zoe Courville http://icestories.exploratorium.edu/dispatches/?p=1528 RECOVERY LAKES, ANTARCTICA– The last month has been a blur of flying snow from my shovel and endless white vistas seen from the windscreen of Jack, the finicky TL6 Berco I take turns driving. Even now, as Ole, our traverse doctor, drives Jack, I am typing in the back seat of the vehicle.

I am always on the move or shoveling, it seems. So far I have dug six 2 meter snow pits at various stops on the traverse. I dig the pits in order to get a close look at the surface snow and the layering caused by different weather and snow deposition events, and because these top 2 meters are fragile enough that the don’t always survive when shipped as cores back to the lab at home. The surface snow holds clues as to what is going on in the ice below. Some of the layering we see in surface pits is seen in deeper ice cores.

We can also get an idea of how much snow has fallen in a given area (thickness of the layers we see) and what processes (wind scours, snow fall) are going on at the surface. It’s a low-tech, labor-intensive way of getting a lot of information. Labor intensive because it involves digging a 2m deep by 1m wide by 2m long hole. I figure I’ve dug about 10 tons of snow so far, and made over 1000 different measurements of density, grain size, air permeability (ease of air flow in the snow), and thermal conductivity (ease of heat flow in the snow). These measurements give a physical basis for interpreting the climate record found in ice cores and the information that can be retrieved about the Antarctic plateau from radar and remote sensing signatures, which depend on, among other factors, grain size and density.


One of my snowpits.

So I’ve been doing a lot of digging on this trip. It is good because if anyone needs to find me I’m either in one of my pits or in the science tent, a nice Weatherhaven tent constructed on the back of one of the sleds that is a mobile snow laboratory, complete with light table for looking at the layering in cores, and all my other equipment, including speakers for my iPod. I hate to admit it, but it’s a nice, more comfortable set-up than the cold room (basically a walk-in freezer converted into a laboratory) I work in back at home. Most days, it is -15 deg C (5 deg F) to -20 deg C (-4 deg F) in the tent, which is unheated to preserve the snow samples I work on, and out of the wind and pretty nice.

In addition to the work I’ve done in the snow pits, I’ve been able to help out with some of the other projects going on around camp. I usually help Tom Neumann with the hand coring we have to do. At each site, we collect what we call Beta cores, which will be cut up, melted, and tested for beta radioactivity. The peak in radioactivity signals the height of atomic bomb testing in the 1960s. This radioactivity was transported through the atmosphere here to East Antarctica in 1963-1964 as snow fall. In this way, we can date the layers in the snow, since we know that the layer with the highest radioactivity is from that year. A bit unsettling perhaps, but very, very useful.


Some of my Arctic teammates hand coring in Greenland last season.

I also helped Dr. Ted Scambos from the National Ice and Snow Data set up a string of temperature sensors we dropped down the last 90m hole we drilled. The temperature at different depths gives an indication of past temperatures, and can be used to determine if this area of Antarctica is getting warmer or colder—this is important since there are no direct measurements of temperature over time here (since there is no one here to make the measurements!)

It’s fun to help out with the other projects, as it gives you a different perspective on what everyone is working on. I also have been logging the boreholes that Lou is drilling with a borehole optical stratigraphy (BOS) system, which is essentially a camera used to record the reflectance of the layers in the hole. I have also been driving the vehicles when we are on the move, usually Jack, which is pulling a load of food and the living module where we eat. This is usually a bit boring as our top speed these days is around 10 km/hr (6.2 mph), which allows for Kirsty to make good measurements using her deep radar system. Faster than that and she does not have as good of a signal. Other times though, like when we are going through a white out, where at times you lose all perspective of what is up or down or where you are, or when the sastrugi are large enough that they cause the whole train you are pulling behind you to lurch sickeningly behind you in the rear view mirrors, it’s a bit stressful. We drive in 6 hour shifts, which gets tiring as well.


The living module speeding along at 10 km/hr.

Jack is a bit difficult to drive. Kjetil, one of the mechanics who was at Camp Winter, where the vehicles were all fixed after last year’s problems, had explained to me that each vehicle is a bit different. The vehicles were all named after famous sled dogs, and the names seem to suit them, which is odd as well. I was skeptical until driving a couple different vehicles. I began by driving Chinook, which is relatively easy to drive. You want to drive in 5th gear, just speed up, put him in 5th, set the remote throttle knob on the dash so that you have about 1900 rpms, and down the ice cap you go.

Jack, on the other hand, is super touchy. It takes about 5-10 minutes of wrangling with the throttle knob to make him stay in 5th, sometimes even 4th. Moving the knob up or down even less than a millimeter sends him either bolting off at 13-15km/hr (way faster than we want to go), or zooming down through the lower gears if the rpms fall off. And then it takes even more finessing of the throttle knob to find Jack’s “sweet spot” where he’s keeping up with the others, but using as little gas a possible. This sweet spot of course is different from day to day as the surface conditions change, soft snow making it harder for him to pull his heavy load, and hard flat snow making him want to take off and pass everyone else. Even better, Jack changes speeds pretty drastically even with the remote throttle in the same position as the surface conditions change. As Svein says, “Jack is special.”

Svein has also encouraged me to try different things: monkeying with the throttle, driving in the tracks of vehicle in front of me, driving out of the tracks of the vehicles in front of me– which I guess makes the drive at least engaging if not relaxing at times. It’s a game to see which driver can get the lowest fuel consumption, as in, “I was getting 32 liters/hour, see if you can beat that.” Anything to make the time go by, I suppose. In a way, Jack reminds me of my dog at home, Baker. He’s stubborn, has a mind of his own, and is a bit crazy at times.


The driving-in-others’-tracks approach.

Besides driving and shoveling, the recreational activities I have managed are knitting (I knit Christmas ornaments for everyone on the traverse and yes, we had a tree—turkey, ham, gravy and stuffing too—we just celebrated on the 27th since that was a more convenient day for us) and skiing. A lot of the people on the traverse like to ski as recreation. It gives us some time to ourselves and away from camp where you can appreciate that you are in the middle of nowhere for a little bit, before scurrying back to the relative comforts of camp. I know that some have a goal of getting out to where they can’t see camp anymore, which no one has managed yet.

I had the full set of Arrested Development DVDs that I would watch at night in my bunk (not wanting to subject the rest of the group to American TV), but I’ve watched all the episodes now, and read the book I brought along, John Behrendt’s Innocents on the Ice, about his Antarctic traverse during the IGY in the 1960s.

It’s fun to think about the differences between our traverses. They definitely had a rougher set-up, while we ride in relative comfort. To be honest, we ride in relative comfort even in modern-day traverse standards, with a kitchen. They had a camping stove, shower (showers are pretty much unheard of in remote camps even today), a separate sleeping module (they slept in benches and sleeping bags in the vehicles) but got to see some fantastic, mountainous scenery, seeing some of the mountains for the first time. They were exploring totally unknown areas, with little warning if they were crossing crevassed areas unless they had a plane to do reconnaissance. We are covering places that haven’t been visited before, but have a pretty good idea of what we are getting into from satellite images, and have a great crevasse detector (Svein, our mountaineer, who operates a radar system that can detect them).

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