Ice Stories: Dispatches From Polar Scientists » AGAP http://icestories.exploratorium.edu/dispatches Mon, 15 Nov 2010 20:40:36 +0000 http://wordpress.org/?v=2.9.2 en hourly 1 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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Our Series of Unfortunate Events http://icestories.exploratorium.edu/dispatches/our-series-of-unfortunate-events/ http://icestories.exploratorium.edu/dispatches/our-series-of-unfortunate-events/#comments Fri, 30 Jan 2009 18:40:27 +0000 Adrienne Block http://icestories.exploratorium.edu/dispatches/?p=1523 January 9, 2009

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.
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A Typical Day in an Atypical Place http://icestories.exploratorium.edu/dispatches/a-typical-day-in-an-atypical-place/ http://icestories.exploratorium.edu/dispatches/a-typical-day-in-an-atypical-place/#comments Sat, 24 Jan 2009 00:30:59 +0000 Adrienne Block http://icestories.exploratorium.edu/dispatches/?p=1514 January 5, 2009

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!

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AGAP South: Population 42 http://icestories.exploratorium.edu/dispatches/agap-south-population-42/ http://icestories.exploratorium.edu/dispatches/agap-south-population-42/#comments Thu, 01 Jan 2009 04:08:04 +0000 Adrienne Block http://icestories.exploratorium.edu/dispatches/?p=1446 December 26, 2008

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!

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The South Pole and Beyond http://icestories.exploratorium.edu/dispatches/the-south-pole-and-beyond/ http://icestories.exploratorium.edu/dispatches/the-south-pole-and-beyond/#comments Tue, 30 Dec 2008 18:53:29 +0000 Adrienne Block http://icestories.exploratorium.edu/dispatches/?p=1434 December 18-23

SUMMER CAMP, SOUTH POLE, ANTARCTICA– So, perhaps I was a bit ahead of schedule when I referred to Friday as the Eve of Discovery. Since then, AGAP has been playing the waiting game. Waiting to get to Pole, waiting to get acclimated at Pole, waiting to get to AGAP-South and now waiting for the rest of the science party to be medically cleared to fly our science missions.

In the midst of all that, I developed and recovered from the intestinal CRUD that was sweeping McMurdo. CRUD is the official term for whatever sickness is sweeping McMurdo in spite of the flu shots and constant handwashing. Initially, the doctors thought I was sick because I had taken Diamox, the recommended medication for altitude adjustment. When I was still eating tea and toast 3 days later, they decided I had had the CRUD. I slept through most of those uncomfortable days and being at Pole was just what I needed to forget being sick.

Eventually, I beat the CRUD and saw my name on the manifest to fly to Pole. We arrived just before midnight on December 18 for a planned 3 days of acclimatization at more than 10,000ft. When my illness resurfaced at Pole (CRUD part 2), I ended up having to stay 2 extra days. Most of my time was spent at Summer Camp, in the South Pole’s sturdy but temporary buildings called Jamesways. Although Summer Camp is a shantytown compared to South Pole Station, it was much more comfortable than I anticipated. We still have running water and plumbing, something I’ll be sure to miss at AGAP, and across from my little haven, there’s a lounge with 2 TVs and room to dance the night away if the spirit so moves you.


Hugging the Ceremonial South Pole.

I was impressed with South Pole Station and since it had so many public spaces, I spent much of my time squatting in the quiet reading room or in one of the lounges where the walls are lined with books. The station manager, who also contributed to the design and construction of the building, gave the AGAP group a behind-the-scenes tour. We learned how the building is designed to recycle all the heat it generates and saw the many 4-wall doors that would be closed if ever there was a station meltdown. Unfortunately, being in such an extreme part of the planet, where the weather can kill you, also means you have to plan for the worst. Everything in the building is duplicated. Each heating system could heat the whole building if the other one broke or needed repair. And on top of that, part of the building is a life preserver; a small section where everything needed for survival can be produced and maintained even if the other parts had to be abandoned.


At the South Pole, I did the ever famous handstand. Everyone wants a chance to hang off the bottom of the world.

I spent most of my last day at South Pole in the growth chamber, a greenhouse within the station where all the vegetables are grown for those that winter-over. It’s also one of the few places you can track down some humidity in the dry polar air. I knew before I came to Antarctica that it was the highest, driest, windiest and coldest place on Earth. But I now have a new appreciation of the high and dry aspects of its character. It’s common for people to get sore throats at night, not because they are developing colds but because it is so dry, it desiccates the back of the throat. In the course of the night, it dries out until the pain of it wakes me up. For the first time in my life, I have taken to sleeping with my water bottle cradled in my hands. But that’s only one of many strange habits I have these days. My favorite is that I have to wear sunglasses to go to the bathroom. Who thinks “Man, I need to go to the bathroom. I better find my sunglasses!” Acclimatizing to life in this frozen wilderness is not too hard when you’re excited about the science but I know I’ll have a whole new appreciation for life in NYC when I get back.

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South Pole Ack Camp http://icestories.exploratorium.edu/dispatches/south-pole-ack-camp/ http://icestories.exploratorium.edu/dispatches/south-pole-ack-camp/#comments Sun, 21 Dec 2008 20:03:59 +0000 Robin Bell http://icestories.exploratorium.edu/dispatches/?p=1384 SOUTH POLE STATION, ANTARCTICA– After more than a month in McMurdo, members of the AGAP team are camping at the South Pole to get our bodies acclimatized to high altitude living. Our destination is AGAP south camp in the East Antarctic Ice Sheet. In this video, I describe the “ack camp” and what’s next for our team.



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Casting Off the Lines http://icestories.exploratorium.edu/dispatches/casting-off-the-lines/ http://icestories.exploratorium.edu/dispatches/casting-off-the-lines/#comments Thu, 20 Nov 2008 18:01:25 +0000 Robin Bell http://icestories.exploratorium.edu/dispatches/?p=1143 CHRISTCHURCH, NEW ZEALAND– It is a quiet spring night in Christchurch, New Zealand. The air is filled with the heavy scent of the spring flowers. In twelve hours if the weather and aircraft cooperate we will take off for Antarctica.

We have completed the familiar routine of sorting through two large orange bags of clothes. I am glad I packed alternatives to the four pairs of wool tube socks I received. I am both groggy from the jet lag and concerned about delayed traverses missing aircraft certifications and dented fuel drums. My achy back makes me fidget. The feeling in my stomach is similar to what you feel in the hours before you cast off the lines from the dock to sail across an ocean. Your head is racing plans, alternative plans and worries but time is running out. Tomorrow morning the lines will be cast off and the focus will be on the here and now.


The Gamburtsev Mountains beneath the ice.

This project to study the Gamburtsev Mountains is the biggest I have ever helped put together. For almost eight years we have been puzzling over the logistics of how to get to this hidden mountain range hidden beneath the largest ice sheet on our planet. They are completely covered with ice. Not a single craggy peak sticks up out of the ice sheet. They are tall – rising about 9000 feet above the surrounding terrain. This means the Gamburtsev Mountains tower over the Appalachians and are about as high as the Alps. They are wide – hundreds of miles wide. If a well-maintained highway cut across them it would take the better part of a day to cross them. But alas there is no highway.


The AGAP Project logo.

We have assembled a multinational team for the International Polar Year from six nations. We developed an expedition consisting of three small scientifically equipped aircraft with over 25 scientists and engineers. But we only have a very short seven weeks when the weather is warm enough to work in. Warm enough means the temperature is warmer than -50 degrees C.

Much has to happen before we can start “doing science”. The two field camps have to be constructed and the fuel to fly the aircraft and heat the buildings has to be delivered. Parts of the plan are beginning to change already. The British plans are delayed due to paperwork and the traverse has had trouble with the crevasses.


One of the partially built AGAP field camps.

The lines for this expedition have been cast from the dock. The here and now has arrived.

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From the Top of the Rock to the Bottom of the World http://icestories.exploratorium.edu/dispatches/from-the-top-of-the-rock-to-the-bottom-of-the-world/ http://icestories.exploratorium.edu/dispatches/from-the-top-of-the-rock-to-the-bottom-of-the-world/#comments Thu, 20 Nov 2008 15:27:00 +0000 Adrienne Block http://icestories.exploratorium.edu/dispatches/?p=1138 Nov 17, 2008

NEW YORK CITY, NEW YORK– In New York City, fall is just beginning its descent into winter. Last night we sank below 40 degrees for the first time and back in my hometown of Columbus, Ohio, it’s beginning to snow. Each time I clutch my scarf a little tighter to protect me from the wind, I try to tell myself to toughen up. I think, “This time next week, you’ll be in Antarctica, sleeping in a snow cave. This time next month you’ll be at AGAP South, where it’s 40 degrees below zero on the most pleasant day.”


A cloud hovering over Lower Manhattan.

While on the subway, I try to imagine a temperature 80 degrees different from today’s and picture myself doing undergraduate fieldwork under the unrelenting sun and heat of a Utah summer. The train stops suddenly and brings me back to NYC… “There are more people in this subway car than there will be at AGAP South.” I look around, noting the diversity: colors, expressions, ages and occupations. It seems the same reason I love living in NY is the same reason I love leaving it. The variety. You can’t beat a career that takes you from “The Top of the Rock” in midtown Manhattan to the bottom of the world.


A Cloud hovering over Beaufort Island.

I’ll arrive on the Ice Monday, November 24… See you there!

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Antarctic Geology http://icestories.exploratorium.edu/dispatches/big-ideas/antarctic-geology/ http://icestories.exploratorium.edu/dispatches/big-ideas/antarctic-geology/#comments Fri, 10 Oct 2008 00:17:45 +0000 Exploratorium http://icestories.exploratorium.edu/dispatches/?page_id=754 under the ice. . .and what they’re finding is a big surprise. ]]>
Geologists collect rock samples in the Transantarctic Mountains.

At first glance, Antarctica seems to turn a cold shoulder to geologists. How do you study minerals and landforms on a continent that’s almost entirely covered by ice? But dauntless geologists are using a full range of tricks to peer under the ice . . . and what they’re finding is a big surprise.


A Twin Otter aircraft casts its shadow as it emits ice-penetrating radar waves. These waves reflect off the bedrock back to the aircraft revealing information about the geology beneath the ice.

A map of the mountains beneath the ice.

Take the apparently flattish slab of ice that is east Antarctica. Hiding beneath is a mountain range to rival the Himalayas, a range known as the Gamburtsev Mountains. These mountains are completely buried by ice, but their presence was first signaled by telltale wobbles in the strength of gravity measured from above.

What’s most surprising about this hidden mountain range is that, by all rights, it shouldn’t be there. East Antarctica is understood to be an ancient continental shield, a stable, unchanging plateau at the center of a tectonic plate, far from the mountain-building phenonena—such as volcanoes and plate collisions—that occur at plate boundaries. The presence of a mountain range in the middle of a continental shield like east Antarctica is, geologically, astounding. Says geologist Robin Bell, “It’s almost as if an archeologist in Egypt opened up a tomb and found an astronaut inside.”

Bell hopes to solve the mystery of the Gamburtsev range using data from roughly 200 flyovers, including radar signals (which penetrate through ice to create an image of the land surface beneath), magnetic measurements, gravity measurements, and laser sounding of the surface ice. This massive data collection effort, called the GAMBIT project, should yield the clues necessary for Bell and other Antarctic geologists to figure out when—and how—the Gamburtsev Mountains formed.


Sediment coring is another method scientists use to study the geology of Antarctica. Analyzing cores like these—from the ANDRILL project on the West Antarctic Ice Sheet—helps scientists understand Antarctica’s past climate and geologic history.

POLENET researchers have to find exposed rock to place their high-precision GPS units. The units are powered by solar panels during the summer and wind generators and batteries during the polar darkness.

Western Antarctica—younger and more geologically active than its eastern counterpart—holds its own share of mysteries. One stands out in literal stark relief: the Transantarctic Mountains. This craggy rock spine erupts from the ice in a line that marks the boundary between east and west Antarctica. The range seems to be associated with a period of rifting—stretching of the earth’s crust—that began in west Antarctica 180 million years ago, and may or may not be ongoing. Data from the POLENET project, mainly from seismic and GPS sensors drilled into coastal bedrock, will help establish whether rifting continues in west Antarctica. “I’m sure that when we get these instruments in place, there are going to be a lot of surprises,” says POLENET geologist Terry Wilson.

Already, GPS data have confirmed that Antarctica is rising (geologists say “rebounding”) from the loss of ice during the last ice age, which ended 12,000 years ago. The land itself is rising just a few millimeters a year. This may seem slight but it’s still enough to significantly impact calculations of the changing thickness of ice sheets. Scientists the world over are watching the Antarctic and Greeland ice sheets with keen interest, because as they melt in response to global warming, global sea level will rise, wiping out coastal communities.

The fate of the ice sheets may rest, literally, on what’s underneath them. Research by Slawek Tulaczyk and others suggests that the motion of ice sheets depends on interactions between the ice and the rock below. Lakes of melted water under the glaciers may reduce friction and cause ice sheets to flow faster to the sea. Meanwhile, the breakup of ice shelves around Antarctica means fewer buttresses to hold back ice sheets from advancing rapidly into the sea.


The Transantarctic Mountains.
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