In the 1970’s, an international effort to fly ice-penetrating radar over Antarctica resulted in the first rough maps of the sub-ice world.  A ski-equipped Navy LC-130 Hercules was outfitted with radar and flown for long distances.  This reconnaissance was invaluable, but the program went by the wayside after the specially modified airplane crashed doing other work.  The concept was largely put aside until the early 1990’s when glaciologists and geologists got together and tried again.  By this point, it was clear to some that critical additional information could be obtained by including other measurements, namely gravity and magnetics to help understand the geology beneath.  Incredibly, the scientists stuffed all these instruments and a laser altimeter (we didn’t have satellite laser altimeters then) into a much smaller aircraft, a deHavilland Twin Otter.  The Otter is much cheaper to operate and supportable at temporary field camps, so it was perfect for high-resolution studies of specific problems.  

A ski-equipped LC-130 Hercules with jet assisted takeoff (JATO).

Field camps were built each season and LC-130’s delivered fuel for the Twin Otter to use.  This went on until 2001 and then again in the 2004-05 season, and many discoveries were made; however, the Twin Otter just can’t reach the deep interior without heavy support, and this has become very expensive.  Such resources are also very limited.  LC-130’s are very costly to operate, are much larger than needed for this type of work, and require a huge ground crew to support.

The Twin Otter.

The Twin Otter flying over Thwaites Glacier Remote Field Camp.

Having outstripped the capacity of Twin Otters, what next? In my next dispatch, I’ll tell you about what might seem an unlikely platform for Antarctica research: a twin engine aircraft that first saw action during World War II.

This one-of-a-kind airplane features an array of instruments for studying the East Antarctic Ice Sheet and the bedrock below: radar, a magnetometer, laser altimeters, and a gravity meter. Skis allow the team to land nearly anywhere in Antarctica if necessary.

The specially-quipped C-47 aircraft is designed to conduct long-range airborne surveys in Antarctica and Greenland.

The East Antarctic Ice Sheet is the sleeping giant of the cryosphere: it covers more than 95% of the Antarctic continent and locks up more than 60% of the world’s supply of fresh water. Considered much more stable than its smaller counterpart in West Antarctica, scientists are turning more attention to studying the history, structure and dynamics of this mysterious icy world. Instead of taking the stability of the ice sheet for granted, scientists from many different countries are digging into East Antarctica’s climate history to help predict how this vast ice sheet could respond in a warming world.

Graduate students Dusty Schroeder (foreground) and Jamin Greenbaum (rear) monitor instruments during a survey flight.

As a member of a research group at the University of Texas, Austin, Jack Holt participated in a multinational project called ICECAP to survey an enormous, unexplored part of the East Antarctica Ice Sheet. Building on their research experience of the last two decades, the UT team employed a ski-equipped aircraft outfitted with unique instrumentation, including an ice-penetrating radar capable of mapping the surface, internal layers, and the bottom of the ice. Other instruments revealed information about the density and type of the underlying rocks. The aircraft was also fitted with a suite of secondary instruments including specialized GPS receivers and cameras. One of the goals of ICECAP was to find the oldest ice on the continent, the site of a future ice-coring project to unlock climate records that go back a million years.

Data from the ICECAP project will help scientists understand how the East Antarctic Ice Sheet, with its enormous supply of fresh water, might react to changing environmental conditions. The ice in the target area is generally over 2 miles (3.5 km) thick and the bedrock lies mostly below sea level, making this ice potentially more likely to make a rapid contribution to sea level rise than the ice sheets in Greenland or West Antarctica. But the largely unknown continent buried beneath is also important for forecasting how the ice might respond to a warming world: The slope and roughness of the ground, the presence of water (including subglacial lakes), and the type of rocks are all factors.

ICECAP season 1 flight lines.

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).

AGAP-SOUTH CAMP, ANTARCTICA– On January 6th, we sat around after dinner discussing how miraculous it was that nothing had gone wrong. This clearly was the cosmic queue for everything to go wrong in the next 27 hours.

First, the inverter blew. The inverter supplies power for the scientific equipment in the plane. Without it, the gravimeter has no blinking lights and collects no data. This flight holds the current record for the shortest flight out of AGAP-south. Beth Burton noticed the lack of power and quickly turned SJB around.

A KBA mechanic works on the left engine of SJB. The plane has been getting a lot of attention lately.

The very next flight, we lost the plane’s tip tanks. In addition to fuel stored near the belly of the plane, there are also gas tanks in the wings. These tip tanks add about 15 minutes of flying capability to any flight out of AGAP and were essential to meeting some of our distant science targets. It was particularly frightening that these pumps malfunctioned when we were considering flying the Recovery Lake lines, which require the use of the plane’s normal tank, the auxillary tank we installed back in McMurdo and the tip tanks.

Finally, in a third stroke of bad luck, we lost the onboard GPS. Without information from our Global Positioning System, we can collect data but we have no idea where we are along the survey line. We know the data represents the Earth… but where on Earth?

Thinking bad things come in 3’s might lead one to believe these would be the end of our troubles but the worst was yet to come. Next the “command center” of the radar system went out. It is as if you were using your home computer and suddenly, you could not see your hard drive anymore. You wouldn’t be able to save new documents, or play your favorite game. It is a situation best described by “Lights on but no one’s home”. Our science team discovered this problem just after I had gotten up for my “night shift” duties. Nick was able to replace the command center and we were still able to fly that day.

Later, in the radar processing, we saw strong vertical offset of the ice sheets internal layers and the bed that lies below. Nick and I set out to investigate this problem by examining an individual radar file from Flight 35, which seemed to be when the problem started. In the end, it turned out that after replacing the radar’s command center, the settings for channel 1 of the radar had been reset but the others (channel 2, 3 and 4) were not set correctly. This was a happy answer to the problem since it meant that we could rescue the data from flights 35-40 if we used channel 1. Not having worked as long or as hard on this project as either Nick, Michael or the PIs at times I feel like the hired help or the free loader who came along because she wanted to be in East Antarctic Field Camp with a population of 31. When I contributed to figuring out why the radar was malfunctioning, that increased my feeling of self worth. I had a moment in which I felt instrumental to ensuring the data quality… not just the making of copies.

A typical radar data product. The bright red line is the surface of mountains under the ice.

This is what the radar looked like after the radar’s command center broke. Fortunately we found the source of this problem and will later be able to recover this data.

Despite all the unfortunate events, the survey has gone well and, I have to say it has gone by fast. It’s hard to believe that we only need 4 more days of good weather to complete our science objectives. It’s hard to put your faith in good weather to make plans for going home but we don’t have much choice. Here’s hoping for clear skies!

A clear day at AGAP-South. This is just the kind of weather we need to complete the survey.

AGAP-SOUTH CAMP, ANTARCTICA– Once we began flying at AGAP, we quickly got into a routine of collecting data, downloading, archiving and running a quality control procedure. We are operating 24 hours a day in two teams. There is almost always someone at the computer copying or reviewing data. Though there have been days that have been flawless, our peak performance of 4 flights per days has been interrupted by weather, which was particularly bad around the New Year.

Life at AGAP revolves around the forecast… which is not always the actual weather. The weather determines if we’ll be allowed to get off the ground and which direction we can point our airplane, SJB. Assuming the weather cooperates, a day in the science tent follows a certain rhythm, paced by the arrival and departure of SJB.

The GAMSEIS science team posed for a group photo before departing AGAP-South.

The day begins with the rising of our day shift operators, Nick and Michael. They pop into the science tent eager to know how things went the night before. The flight plan for that morning has usually been selected a day or two in advance. On the morning of the flight, it is relayed to the pilots and our flight operator, the scientist who makes sure all our equipment is up and running before and during the flight.

Thirty minutes before we leave the ground, our base stations have to be on. Base stations collect a similar type of data as equipment on the plane, but are in a fixed position just outside our science tent. We have base stations for the GPS and magnetic data. The GPS base station is required so we know where the plane is relative to camp. The magnetic base station is needed to capture how the magnetic field is varying in time, while SJB’s onboard system captures how the magnetic field varies in space. The Earth’s magnetic field varies in time in part because of currents in the liquid part of the core of the Earth (i.e. the liquid outer core). The magnetic field varies in space because of different rock types under the ice. By collecting data at the base station and onboard SJB, we are able to separate the changes in time, which we are not studying, from the changes in space which relate to the rocks we see on the radar lines.

Pondering GPS data in the Science Tent.

While SJB is in the air, we are in the office making copies of the data. This is particularly time consuming for the radar data because of its volume. Copying the radar drives takes so long that we have one computer and one person, Chris, designated to the task. After the radar copy is complete, a sampling of the data is plotted and reviewed. Meanwhile, similar procedures are executed on the magnetic, GPS and laser data from the previous night’s flight. Although not an exciting aspect of the work, the QC (quality control) step is essential. It is during this step we identify survey lines that might need to be reflown and also get a sense of how well our system is working.

Working in the science tent again… This actually a different day! Note the eery similarities.

When the plane returns, it is greeted by a flurry of activity. The camp staff are ready to refuel, Chris or Nick will take blank hard drives out to the airplane and swap them for the ones containing the radar data for the flight, Stefan and Dan check on the status of the gravimeter. The flight operator brings in written logs and data on memory cards to archive and copy. The plane only sits unattended in between the day and night shift, while the whole camp is having dinner or on bad weather days.

The pace of the survey makes the days go by quickly. I keep forgetting that the GAMSEIS team is done with their work and gone already! I still expect them to come back from an installation and be sitting in the galley at dinner. With 4 flights a day, we are just barely keeping up with the in-flux of data, which is good because you need something to do in this place or you’ll feel trapped. Fortunately, I never feel trapped when surrounded by science!

SOUTH POLE STATION, ANTARCTICA– Let it begin!

Another concerted effort today to get the train packed up. We will have an open house this evening for our fellow residents of the South Pole, and so we are also trying to clean up a little bit.

We’ve had visitors stop by quite often while we’ve been here — today some folks from IceCube stopped by, and the day before that, members of the Heavy Traverse, which pulled over one million pounds of cargo from McMurdo to here, came by as well. Today will be a little more formal, with everyone at the station invited.

The last of the cargo is making its way to the sleds, and we will also (with any luck) do a last test of the radar systems tomorrow on a little longer test drive. Then we’ll pack up the radar equipment and get on down the road.

Anna Sinisalo prepares her radar system for the last radar test tomorrow on Sembla.

AGAP-SOUTH CAMP, ANTARCTICA– There are finally planes in the airspace of AGAP-South! We flew our first survey lines during the transit of scientists from Pole to our main camp. With the first flight, came the first observation of peaked bedrock under relatively thin ice. Thus far the radar shows the bedrock to be about 1.8 miles below the ice sheet surface and its elevation varies in some regions by up to half a mile. Hard to believe that just under this endless expanse of ice there are mountains. It’s such a secretive part of the world.

While our research group is here doing an airborne survey, another group based out of Penn State University is installing and servicing seismometers. The airborne side is called GAMBIT while the seismic side is called GAMSEIS. Together we are the AGAP project and the occupants of AGAP-South.

View across AGAP-South at one of the rare times when both planes are grounded.

Unlike the work I am here to do, GAMSEIS is a multi-year project that began last year. Over the course of the project, whenever there is a large enough earthquake, waves of energy will pass through the earth and be recorded at the GAMSEIS seismic stations. The GAMSEIS group will return and collect their seismometers along with the record of seismic events. Using those data, they’ll be able to piece together the story underlying the Gamburtsev Subglacial Mountains. We’ll better understand how the mountains were built and the nature of the mantle, the molten layer of Earth, that lies below.

This is the inside of the Jamesway tent where the scientists sleep. It’s hot, crowded but somehow still a welcome change from being outdoors.

The weather on Christmas Day forced us to take a break and enjoy the holiday. Both science teams were grounded due to low visibility caused by blowing snow coming out of the South. Despite our 24-hour schedule, dinner at AGAP is the meal most of our population of 42 actually are awake and present to eat. It falls right between the morning flight and evening flight for both science groups and those working the night shift have usually just gotten up. Although one of the cooks is suffering a rib injury, Christmas Dinner was a meal to be reckoned with. It was also a great chance for the whole camp to relax and get to know each other individually rather than categorically as science, flight crew, or staff.

For me part of the holiday excitement was that those of us on the GAMBIT side got to share some of our first data products! We’ve waiting a long time to see these radar profiles with plenty of peaks! The days ahead hold a lot of the same, but there are still firsts and discoveries to be made. I wonder when we will find the biggest mountain peaks and the biggest lake!

Because being at high altitude can make some people sick, the science team has to be trained on multiple parts of the airplane’s science equipment.

During June this year, we tested our radar system in Greenland. We flew over the Greenland Ice Sheet, collecting data to image the ice down to 2.5 km (1.6 miles) below the lake-spotted surface. Now in Antarctica, we face the challenge of imaging more than 4 km of ice…. That’s 2.5 miles of frozen history between our science team and the Gamburtsev Mountains we came here to study! Because we have to reach further into the ice, we have more data than ever coming back after each flight. There’s so much data that the system chokes on it and gasps, “Help me, Adrienne. Help!”

I have escaped the office a few times this week. I got to go on a tour of the pressure ridges that form between the flowing ice of the Ross Ice Shelf and the rock that stands firm against it. And just last night, I escaped to Scott Base, the Antarctic Base that belongs to New Zealand, for some retail therapy. My Scott Excursion really took my mind off of the software for a while and had me refreshed and ready to go back to Radar World this morning. Not to mention I am well stocked on wooly base layers to fight the cold.

View of Scott Base from the Pressure Ridges.

An interesting formation in the Pressure Ridges. What do you think it looks like?

Today, I feel the same way I do when I am at the top of the big hill at the beginning of the ride. There’s that moment when you lift off your seat before powering down the steep hill, screaming your head off. I have been living there, in that emotional suspension for 3 days. Part of my jitteriness the last few days is undoubtedly rooted in the fact I’ll be going to the South Pole on Monday. According to our medical briefing, that means I’ll be perpetually short of breath, having trouble sleeping and going to the bathroom about every 20 minutes for 2 days…. The anticipation is almost too much to hold in! I have been to 10,000ft elevation before but that was after living at 6,500ft above sea level for 5 weeks… and that was in Utah. The transition from sea level here in McMurdo to 10,000ft is such a surprise to the system that everyone is prescribed a medication to help our bodies adjust to the lower oxygen levels. On top of that, we all have to fight off the adrenaline brought on by the fact we’re in Antarctica, at The South Pole, at 10,000ft—no offense to Utah, but it doesn’t compare! Just in case we don’t adjust to the elevation, everyone has been learning tasks outside their specialty. Hopefully, if someone gets sick, we’ll be able to keep the science moving forward, even if at a slower pace.

In the end, it’s not just where we’ll be a week from now. It’s what we’ll learn. The Gamburtsev Mountains have been enigmatic since their happenstance discovery in 1958. Soon, we’ll know them in a way only dreamt of until now. The people on this science team will learn more about the Mountains than the rest of the world has compiled in the last 50 years. This is the Eve of Discovery.