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Pine Island Glacier 2011: It’s Showtime!

December 9th, 2011 by Maria-Jose Viñas

By Bob Bindschadler

Greenbelt (MD), 23 November — After years of waiting, our time has finally come. The years have not been empty. There have been hundreds of e-mails, scores of telephone conferences and a handful of face-to-face meetings to iron out the mountain of details required to support more than a dozen scientists’ intent of unlocking critical mysteries within the light-less, frigid void beneath a thick floating plate of ice in one of the most remote regions on earth: the Pine Island Glacier.

Map showing the location of Pine Island Glacier, which is almost 1,400 miles (2,200 kilometers) away from McMurdo Station.

What causes my team of scientific experts and me to focus on this seemingly innocuous location is a silent change that is unfolding and already affecting millions of people in their everyday existence, quietly threatening billions more. Ice sheets, those vast continental-sized slabs of ice in Greenland and Antarctica, are shrinking. The ice they are shedding is raising sea level across the globe. This is bad news. The good news is that the rise is gradual. My job is to understand the processes that cause ice sheets to shrink so that credible projections can be shared with policy makers and planners. If we get this right, societies will have the chance to adjust to rising sea level in a deliberate manner and minimize the human and economic impacts.

We are heading to a particularly remote corner of the planet, expecting to be greeted with bone-chilling temperatures, violent winds and dangerous crevasses (deep cracks in the ice) because this is where satellite data tells us that the Antarctic ice sheet is losing ice most rapidly. The Pine Island Glacier (called PIG, for short, from here on,) has nearly doubled it speed in the past 15 years and is thinning at rates of nearly 10 meters (30 feet) per year. It alone is responsible for 7 percent of the total global rate of sea level rise. The pattern of change satellites have captured shows that the changes are greatest at the coast and decrease inland. That means the trigger for these changes is located at the coast where the ice meets the ocean. PIG is 1200 meters (4000 feet) deep at the coast where it plows into the ocean forming a thick floating ice shelf. As the glacier forces its way into the frigid waters, the ocean resists its icy intrusion. The ice shelf can be thought of as a plug that limits the rate at which the PIG can drain the ice sheet. The little Dutch boy’s thumb inserted into the dike to hold back the sea is a particularly apt metaphor, in this case.

The problem is that the ocean is melting the underside of this PIG ice shelf, making it thinner and allowing the PIG to flow faster. This is what we’ve come to study. This is where the key to ice sheet stability and future sea level will be revealed. Damn the wind, damn the cold, damn the crevasses—we are on a mission and we will get our answers. This is the level of drive and determination that is required to do the work we have given ourselves.

In future blog posts, we’ll write about who we are, what we plan to do and, inevitably, how our initial plan changes as we wrestle with Mother Nature. For now I hope this captures your interest and sets the stage. I have had the luxury this year (this will be my sixteenth Antarctic expedition I’ve led) of enjoying Thanksgiving with my family, but already my mind is turning southward and my packing occupies a large corner of my bedroom. Yesterday was my last day in the office and I couldn’t leave with the others who were thinking most about tomorrow’s Thanksgiving pleasures until I felt all the unfinished work I left behind could withstand a two-month hiatus. It felt strange to close the office door that final time, but once I imagined the house lights being turned down on all the other work, I could feel the glare of the stage lights being cranked up to their full brightness on this field expedition. It’s showtime! The waiting and planning are over and this adventure is about to begin.

Learn more about the Pine Island Glacier expedition on the project’s website, or by reading this NASA web feature.

SEAT: Satellite Era Accumulation Traverse: Happy Sunday Around McMurdo

December 6th, 2011 by Maria-Jose Viñas

By Clement Miege

Hello everybody! This is Clement, for my first blog post! Sunday, November 27 was our day off, so we went exploring the surroundings of McMurdo Station. At around noon, Michelle and Lora decided to go cross-country skiing on sea ice while Jessica and Randy went to Scott Base for some shopping at the Kiwi store, which is stocked with lots of Antarctic T-shirts and other souvenirs.

On our side, Ludo and I took advantage of the wonderful weather and hiked the Castle Rock loop. I hiked this trail last year and it is by far my favorite walk near the station. We started at the fire house at around 11:30 AM. Because the trail is pretty long (9.8 miles), we were required to take a radio with us and give our estimated return time and the contact info for our point of contact in town to the responder on duty at the firehouse.

The walk toward the summit of Castle Rock is very pretty, with amazing views everywhere: behind us, we had Mount Discovery and the Royal Society Mountain Range. In front of us, we had incredible scenery with Castle Rock in front of Mount Erebus and Mount Terror. While approaching Castle Rock, we were able to enjoy a nice scramble leading us to the summit, with fixed ropes set for safety on the ascent. After a quick break at the summit, where it was really windy, we decided to head back down.

Here is our hike in pictures so you can enjoy it as well.

One of the three “apples” that you can find along the Castle Rock loop —a warm emergency shelter and a good spot for resting safe from the wind.

Castle Rock on the left, with Mount Erebus in the background.

Ludo and I: Happy faces at the Castle Rock summit!

Open water, and huge tabular icebergs. The ocean is not far from town — in January, an icebreaker will open a path to get to McMurdo and resupply the station.

Ludo, following the flag line on his sled!

It took us about 4 hours to walk/slide through the whole loop. In fact, we cheated a little bit, taking advantage of the last shuttle to go back to McMurdo station from Scott Base, which knocked off about 2 miles. It was a wonderful trip; it was good to be outside while the weather was nice!

But that wasn’t the end of our day! After dinner, Jessica, Randy, Ludo and I went with a small group to Pegasus runway, an airfield near Mc Murdo station, to visit the remnants of a plane that crashed in 1970 and got stuck in the ice. It took us an hour to get there, travelling in a Delta. After spending a little time checking out the plane, we got back to the station at around 8:30 PM, ready to go to bed after a long day of adventures outside.

Jessica, Ludo, Randy and I are standing on the tail of Pegasus. It was the first time that I got to walk on top of a plane, pretty cool!

Pegasus, with visitors.

Here are some bits of info that I was able to collect on this crash, where fortunately nobody died. The plane, a C-121J named Pegasus, took off from Christchurch, New Zealand in October 1970. The flight to McMurdo went well until a storm started developing near the runway. Unfortunately, the flight had already passed the point of safe return, which meant that it did not have enough fuel to make it back to Christchurch. The only choice remaining was trying to land with no visibility. After a long time circling above the runway to get a little bit of visual information, the pilots attempted to land and the plane slid into a heavy snowdrift deposed by the storm, spun and broke its entire right wing and finally stopped. Luckily, nobody died in this accident.

If you would like to get more information on this story, follow this link.

Now this site is becoming a touristic attraction but it still shows a part of the Antarctic history. After this dramatic event, more precautions have been taken to allow planes to boomerang back to Christchurch if they run into bad weather.

SEAT: Satellite Era Accumulation Traverse: Ice cores: From Antarctica to the lab

November 4th, 2011 by Maria-Jose Viñas

By Lora Koenig

Two weeks ago, I traveled to Utah to help the team finalize planning for this season and to visit the ice core lab and our 2010 ice cores at BYU. The entire was there, except for Ludo, who was in Hawaii competing in a triathlon. (Ludo is not only a top scientist but a top triathlete. I hope he is not getting too use to the warm weather because in less than a month he will be facing temperatures around 0°F.)

There were a few tasks to complete in Utah. The first was to look at many different types of satellite data on the region where we will be traveling to make sure there aren’t any crevasses or other dangers along the route. A crevasse is a crack in the ice. As the ice flows (yes, ice flows just like a mound of putty), it can crack when it goes over a bump or accelerates. Here is a recent picture of crevasses in Western Antarctica, from a NASA Operation IceBridge flight.

Photo Credit: Michael Studinger/NASA

As you can imagine, we would not want to drive a snowmobile in an area like this. So we spent hours looking over maps of the rock bed under the ice sheet to look for bumps, visible and radar satellite images of the surface of the ice sheet, and satellite data showing the velocity of ice flow to make sure that we are traveling on the safest possible route. We ended up moving one ice core drilling location slightly to avoid a dark spot that we could not clearly identify in one of the radar images, just to be extra cautious. Once the route was established, we generated waypoints (coordinates) every kilometer to load into the GPS units that we will use for navigation. The place we are going to is big, white and flat: It is very easy to lose your sense of direction, so we rely heavily on GPS units for navigation.

For some great images and videos on how ice flows in Antarctica please check out this video, made by our NASA colleague Eric Rignot who (thanks again, Eric!) also checked the data that sits behind these videos to help ensure our safe route.

If you would like an in-depth look, this file, which opens on Google Earth, shows our final route with points every 1 km.

Our second task in Utah was to visit last year’s ice cores and have our first meeting to discuss the initial data coming from them. First, here is a picture of a core in the field, taken in December 2010.

In this photo, Michelle (right) is labeling the core and I (left) am getting the core tube ready for storage. The arrow on the ice core bag shows which direction is up.  It is very important that all the cores are labeled in order, or we would lose our time series. The metallic tube in the center left of the picture protects the core during shipping. The core in the tube gets placed in the white core box sitting open on the left side of the picture. (Also, notice that Michelle is standing on a bright green pad to help insulate her feet from the cold snow. It’s a veteran trick for keeping your toes warm.)

Here is that same core in the lab today.

Summer is holding what was about 8 feet of the core and the rest of the about 50 feet of core is stacked in the boxes behind her, waiting for analysis.

Here is a very basic explanation of what happens to the cores once they arrive at Summer’s lab at BYU. (Normally, Summer would be the one writing this, but she is currently studying glaciers in Bhutan.)

When the core arrives, we put it in the freezer.  Here is Landon peering out of the freezer door:

In the freezer, we weigh the core to determine its density and measure its electrical conductivity, which tells us about its chemical composition. A volcanic event would be detected in the cores by the electrical conductivity and can be used to set a point in time. We take all these measurements twice, or even three times, to make sure they are accurate.

Here is a picture of a core that Landon is preparing, sitting on the freezer’s core handling tray:

This freezer is set to -4°F, so when not posing for a picture, Landon would normally be in a parka with gloves on.  As you can see, the core is still in its protective bag, which will be removed when actually processing the core. From here, the core is cut up into sections less than an inch (2 cm) long, and melted for the next stage of analysis.

I will add a quick note here that on last year’s traverse Landon was our lead driller. Both Landon and Jessica are masters students at BYU. They are not only integral players of the field teams, but are also the lead students for the lab analysis of these cores.

Once we have melted the core and put it in a bottle, we send it over to Jessica.

Here is Jessica operating the mass spectrometer (black box to the left in the picture with the blue screen) that will measure the stable water isotopes used to date the core. The isotopes in the snow have an annual cycle and it is this cycle that determines age of the core.  An isotope is an atom, in our case an oxygen atom, that has different variations with different number of neutrons and atomic numbers.  Oxygen has three stable isotopes: 16O, 17O, and 18O.  The peaks and valleys in the ratios of 18O/16O reflect the warmer (summer) and cooler (winter) temperatures, respectively.   Once the mass spectrometer determines the number of isotopes, we can establish the age of the core, in a way similar to counting tree rings. During this process, the core is in the little blue vials just to the right of Jessica.

After spending some time in the lab, we looked at the data from the first core that has been analyzed.  At this point the density and isotopes have been measured and Summer is carefully working to put together the depth-age scale, which is the age of the core at each depth where the core use to sit in the ice sheet.  I will use the density data from the core to determine an age-depth scale from the layers in the radar data and if all goes well the radar and ice core will line up giving us confidence in our analysis.

Last Monday, when I returned to Goddard, I had received my travel itinerary.  We will be leaving the U.S. on Nov 17th to make our journey down to Antarctica.  With all of this preparation, I am eagerly awaiting getting my feet on the Ice.

SEAT: Satellite Era Accumulation Traverse: When Canada Stands In for Antarctica

October 21st, 2011 by Patrick Lynch

By Summer Ruper

Hello SEAT blog followers. I am Summer Ruper, and I would like to share with you a little bit of the ice coring adventure that begins well before the field team heads to Antarctica. Before we start drilling ice cores in the harsh cold and wind of Antarctica, we have to train our field team on the drill and sampling procedures. To do this, we took a trip to a slightly warmer region with ice: Athabasca Glacier in the Columbia Ice Field. Athabasca Glacier is near the Canadian town of Banff, and is one of the most visited glaciers in the world. It’s a beautiful area, and plenty of ice to play with.

To begin, we must first answer the question: What is an ice core? Simply put, it is a core sample collected from a glacier or ice sheet. But the ice core is not entirely made up of ice; with the snow fall and wind also come dust, salts, and even ash from volcanic eruptions. All of this is contained in the ice cores and provides information about how snowfall, temperature, and winds have changed over time. A lot of important information is buried in the ice and snow on glaciers and ice sheets, but you have to get the ice out in order to get at that information.

Piece of ice with bubbles inside. These bubbles provide information on the composition of the atmosphere at the time they were trapped in the ice.

Piece of ice with bubbles inside. These bubbles provide information on the composition of the atmosphere at the time they were trapped in the ice.

In order to collect the ice cores, we use a specially designed ice core drill. The one we use is called the FELICS, and is designed and manufactured by Felix and Dieter Stampfli in Switzerland. Basically, the drill has a sharp ring on the end that cuts the ice and feeds the core into a one-meter long barrel. We pull the one-meter section up, empty it out of the barrel, and then drill another one-meter ice core from the bottom of the hole. We do this over and over again until we have drilled to a depth of about 20 meters, and have about 20 one-meter long ice cores.

Randy Skinner, Jessica Williams, and BYU students drilling an ice core on Athabasca Glacier.

Randy Skinner, Jessica Williams, and BYU students drilling an ice core on Athabasca Glacier.

On Athabasca Glacier, our field crew learned how to operate the drill, handle the ice cores, and generally deal with problems that might arise. We were also able to show the tourists visiting that glacier how the drill worked, let them see (and taste) the ice, and share a little of our knowledge and excitement about glaciers and the environmental records contained in the ice. We had a lot of fun, and Jessica and Randy are excited to transfer this experience to our work on the Antarctic ice sheet soon.

Summer Rupper showing an ice core to group of tourists on Athabasca Glacier.

Randy Skinner “sharing” an ice core with a budding glaciologist.

In another post, we will show you what we do with the ice cores once they return to the lab and share some of our preliminary results from last year’s ice cores.

Jessica Williams, Randy Skinner, and Summer Rupper look for the “perfect” spot to drill a core.

Jessica Williams, Randy Skinner, and Summer Rupper look for the “perfect” spot to drill a core.

SEAT: Satellite Era Accumulation Traverse: How Much Does It Snow In Antarctica?

October 4th, 2011 by Patrick Lynch

By Lora Koenig

Hello!  My name is Lora Koenig and I would like to welcome you to our Satellite Era Accumulation Traverse blog.  I know that is a mouthful so we will call it the SEAT blog. So have a SEAT, grab a hot drink, and enjoy the blog. From now until mid-January, my colleagues and I will tell you about our science and adventures, from preparing our gear in the U.S. to riding snowmobiles across West Antarctica in order to study how much snow falls in Antarctica.  You will hear about our team’s journey to Antarctica, the science we are doing and share in the fun we have while conducting field work in the coldest, driest, remotest and, forgive the pun, coolest continent on Earth.   We are headed to the West Antarctica Ice Sheet, to a place called Byrd Station.

Byrd Station sits amid the vast West Antarctic Ice Sheet, the scientific target of this two-year campaign to study how much snow has fallen there each year in the past thirty years.

I suppose I should start with a short background of why exactly we are headed off to Antarctica and what we plan on doing there.  But first a question: Have you ever wondered how we measure snow fall in Antarctica?   It is actually rather difficult because, quite frankly, there are not a lot of people around with rulers.   In the interior of the ice sheet, where we are headed, the snow falls each year and creates layers like a stack of pancakes — one pancake per year. The best way to measure snowfall, or accumulation, is by using ice cores that drill into the snow.  Think of taking a straw and sticking it into your stack of pancakes and then measuring the thickness of each pancake.  During this project we will be taking ice cores as well as using radars, that image the snow layers between the ice cores to measure accumulation rate, how much snow fell each year, over the past 30 years, the satellite era.  It is our goal to use the data we get from our field-work to be able to better measure accumulation directly from satellites in the future.

Fantastic sundog

The Antarctic sun creates a spectacular "sundog" behind Lora Koenig during her team's 2010 traverse in West Antarctica. The field campaign resumes this fall to study how much snow falls each year on the bottom of the world. Ice crystals in the atmosphere act as a prism to create this halo effect. Credit: Lora Koenig/NASA

That was a short introduction to the science. We will give you many more details as this blog develops between now and the end of the traverse in January 2011.   For now I want to introduce you to the team.   This project is funded by the National Science Foundation and NASA so we have team members from both NASA Goddard Space Flight Center and universities.   The team members  this season include: Jessica Williams, Randy Skinner and Summer Rupper from Brigham Young University; Clément Miège and Rick Forster from the University of Utah; Michelle Koutnik from the University of Copenhagen; and Ludovic Brucker and me, from Goddard Space Flight Center. In the next post, we will tell you about testing the ice core drill in Canada and preparing the radars for their trip to Antarctica. But first, meet the team:

Hi, my name is Jessica Williams and I just started my master’s degree at Brigham Young University in the Department of Geological Sciences.  I am currently working with Dr. Summer Rupper looking at the snow and ice records from the surface of Antarctica. I am excited to go to Antarctica to drill some ice cores to take back to the lab at BYU to study. Using a combination of density, electrical conductivity, and isotope records from the ice cores we will be able to get snow accumulation rates in West Antarctica. In preparation for this trip I went to Switzerland and Canada to practice using the drill and to gain experience living on the ice.

My name is Randy Skinner and I am a geology professor at Brigham Young University in Provo, Utah. On an annual basis I instruct nearly 1,000 students, most in basic geology 101 classes.  In Antarctica I will be involved in helping to obtain ice cores and digging snow pits. The ice cores will penetrate down to a depth of 20 meters. We will drill 10 of these cores while making our traverse of several hundred kilometers in western Antarctica. The cores and information from the snow pits will be used to determine rates of snow accumulation.  I am very excited to be a part of this research, and to bring these experiences back to share with my future students.

Hi! I am Summer Rupper, and I am a professor in the geology department at Brigham Young University, Utah.  My research is largely focused on the interplay between glaciers and climate.  In particular for our work in Antarctica, my students and I are using the physical and chemical properties of ice to reconstruct the past 30-40 years of temperature and snow accumulation rates.  I was in Antarctica last year helping our team drill ice cores for this research.  This year, I, along with my students, will be continuing the processing of those ice cores in our freezer lab at Brigham Young, while the rest of the team heads back to Antarctica to collect more cores.  I am very excited to have such a great team going to Antarctica again this year, and can’t wait to hear all about their adventures upon their safe return.

Camping on the Ice

On Dec. 10, 2010, the science team set up one of four campsites used during the 2010 leg of the two-year campaign. The vastness of West Antarctica makes finding an open camp site rather simple. Credit: Lora Koenig/NASA

My name is Michelle Koutnik and I work at the Center for Ice and Climate at the University of Copenhagen in Denmark.  I grew up in Southern California, but now I enjoy living in Northern Europe.  I was in Antarctica last season as part of this project and I look forward to a second traverse across Central West Antarctica.  I use computer models of ice-sheet flow to understand ice-sheet evolution over tens of thousands of years.  This project is different because we focus on ice-sheet evolution over tens of years.  I have been working on a computer model focused in the region of Antarctica that we will be doing field work — I am excited for a real trip there instead of just a virtual one!  It will be great to face the challenges of the Antarctic environment and also to work with this team to accomplish our goals.

I am Clément Miège, a PhD student in the Department of Geography at the University of Utah. I am originally from France and I am currently working with Dr. Richard Forster on Greenland and Antarctic snow accumulation patterns. This year will be my second Antarctic field season. During this traverse, I will operate 2 high-frequency radars, in order to produce images of internal snow/firn layers. Later, those images will be used, with the help of ice cores, to give us snow accumulation rates. So we will be able to understand 30-40 years of history for this part of the ice sheet. I am very excited to be on this traverse to keep exploring Antarctica and share this extraordinary experience!!

Preparing Core Samples

Michelle Koutnik, of the University of Copenhagen's Center for Ice and Climate, prepared a core of Antarctic ice to be wrapped and put into core tubes for transport back to labs at Brigham Young University in Utah. But first, Koutnik measured the core's length, diameter and weight. Credit: Lora Koenig/NASA

Hi there! I’m Ludovic Brucker, one of the French citizens on the team.  I came to the US in early 2010 after defending my PhD on passive microwave remote sensing of Antarctic snow. I’m currently a scientist at NASA Goddard Earth Sciences Technology and Research (GESTAR) Studies and Investigations, Universities Space Research Association (USRA), Greenbelt, MD.  This season sounds incredibly exciting and I look forward to our deployment on the West Antarctic Ice Sheet to conduct a 400 miles (~650 km) scientific traverse with snow mobiles! After three years studying the evolution of Antarctic snow properties through the use of satellite observations, I’ll now have a chance to see how the snow really looks! I can’t wait to be on the ice and see how correct, or not, my ideas of Antarctica are!

My name is Lora Koenig and I am a physical scientist in the Cryospheric Sciences Branch at NASA’s Goddard Space Flight Center.  I am a remote-sensing glaciologist who uses satellites to monitor the ice sheets and I am always interested in how well measurements from space compare to those taken on the ground. My interest in ground truth data and learning more about ice sheets will take me to Antarctica for a third time this season.   I have always loved snow and ice.  I started skiing in the Pacific Northwest before I started school and my love for being in cold outdoor places continued into graduate school where I studied topics dealing with both seasonal snow and the polar ice sheets.   My expertise is in microwave remote sensing of the ice sheets.

 

Notes from the Field