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Real-time Observations of Greenland's Under-ice Environment (ROGUE): Our Traveling Roadshow

May 19th, 2011 by Matt Hoffman

May 16, 2011

The team packed and ready to depart for a day’s work. One person drives the snowmobile while the other rides on the sled with the cargo to mitigate the hazard of crevasses. Credit: NASA/Matt Hoffman

Each day we traveled to a new site in the area around Swiss Camp and set up a new GPS station on the ice sheet. We looked a bit like an Arctic version of the Beverly Hillbillies with Tom puttering the snowmobile out of camp pulling a big red sled piled up with boxes, bags, shovels, more boxes, pipes, solar panels, more pipes, and me precariously perched on top of it all. We crawled around at about 10 miles per hour to avoid rattling my teeth too much, especially when the wind has sculpted the blowing snow into crusty dunes called sastrugi. Our commute typically took about an hour which can be relaxing if the snow is soft and the weather is sunny and calm, or exhausting when it is windy and bumpy.

The view from the sled. The area around Swiss Camp is covered by a series of subtle hills and valleys that provide some variety to the commute. Credit: NASA/Matt Hoffman

Because the ice sheet is pretty featureless, we traveled by GPS to locations that we had pre-determined but never visited. These x’s in the snow were chosen to provide information about both local and regional ice motion around our future drill sites. It’s a bit funny to travel to a specific spot on the ground that looks pretty much like every other spot from horizon to horizon. It’s also a bit funny to use a $100 handheld GPS to locate the site to install a high-precision GPS station, but you’ve got to use the right tool for the job.  Handheld GPS navigation revolutionized travel across the flat white terrain of the ice sheet – without it, losing sight of camp from fog or traveling too far could be disastrous.

Even with GPS, traveling across the snow covered ice sheet can be disorienting under heavy cloud cover when the light is flat and the horizon disappears into a monotonous world of white in all directions. In those conditions, bumps in the snow are only apparent after you have driven over them too fast, and it’s really hard to tell how big anything is. One afternoon I was driving home in poor light, and about half way back I swore there was a little bug flying along side of the snowmobile. My initial (perhaps irrational) thought was that a fly had somehow been blown up onto the ice sheet and happened to be going the same way we were going. I was so convinced by what my eyes were telling me that I started to speed up to keep pace with the intrepid little guy who miraculously was cruising along at about 13 mph. After about a minute of this nonsense, my depth perception instantly snapped into place, and I realized that the fly was actually the GPS station we had set out the day before, about a half mile off in the distance. That night after dinner, Tom regaled us with stories of poor light in Antarctica that was so bad that you could hardly tell which way was up or if you were even moving!

Matt captures a picture of the World's Smallest Man! The lack of surface definition makes Matt and his subject appear to be in the same plane. In fact, the subject is actually over 8 feet tall! (no, not really...). Credit: Nestor Rial

We were fortunate on this trip to generally have very good weather. On sunny days, the appearance of the subtle hills and valleys that cover this part of the ice sheet broke up the monotony, and the interplay of the low-angle afternoon sun on the snowdrifts created glittering sculptures of light and shadow that unfolded before us as we drove home.

The landscape we travel through is not completely flat and white -- at least not when the sun is shining. Credit: NASA/Matt Hoffman

ROGUE: Real-time Observations of Greenland’s Under-ice Environment
The goal of the ROGUE project is to examine the nature and cause of short-term ice velocity changes near Swiss Camp, Greenland, by observing interactions between the ice sheet, the atmosphere and the bed.

MABEL: Spring 2011: What Is ROGUE and What Has It Done For Me Lately?

May 19th, 2011 by Tom Neumann

May 16, 2011

We installed our stations in spring, when the ample snow cover makes travel by snow mobile possible. Here, Matt notes the station location in a log book. Credit: Tom Neumann

On the way up to Greenland a few weeks ago, we discussed very briefly the science that has brought us here to Greenland this spring. Now that we have some pictures of our work, let’s discuss it in a bit more detail.  As you already know, Matt and I were traveling about by snowmobile to establish GPS stations to measure ice sheet motion. The major goal of the project is to monitor the conditions at the bottom of the ice sheet and record how the environment down there changes with time. Our part of the project will record how the ice sheet velocity at the surface changes, by installing a network of GPS stations near Swiss Camp.

There has been a significant amount of research conducted in the Swiss Camp region over the past several decades. Among other work, researchers have mapped the ice thickness, the ice surface topography, the temperature and wind speed, and the ice sheet velocity. On the map, our GPS stations are indicated by the red dots, while the yellow stars indicate our two drilling locations. The blue triangles are monitoring sites maintained by Koni Steffen and measure the local meteorology as well as ice motion (in a long-term monitoring project by NASA scientist H.J. Zwally). The red curve represents a flow line — a path along which ice flows. If one were to put a marker on the flow line near the Swiss Camp station in the upper right of the map, it would travel down the ice sheet along the red path. Data indicate that ice flowing along our path ultimately ends in a fjord that connects to the ocean. The red dot on bedrock in the upper left (QING) is our base station — a GPS station placed on rock that is essentially immobile, at least over the time period of this study.

Yellow stars mark hot-water drilling locations, while red dots indicate positions of the GPS stations Matt and I installed this spring. The somewhat cryptic naming scheme for the GPS stations indicate the distance from the ice edge as well as the distance north or south of the flowline. Hence, station 28N4 is 28 kilometers upstream from the end of the flowline and 4 kilometers north of it. Credit: Matt Hoffman

Our prior work in the area demonstrated that the surface velocity of the ice sheet is essentially the same between stations just 2 or 3 kilometers apart, but can be markedly different between points 5 or more kilometers apart. We also found that the velocity can change quickly during the summer, when lake drainages our common. The locations of our network of GPS stations (as shown on the map) are chosen to capture both the short term changes in velocity due to surface water drainage (which our sensors at the ice sheet bed should also record) as well as capture the spatial variability over a wide range of ice sheet surface elevation and ice thickness.

During summer, melting snow at the surface collects into streams, rivers and lakes at the ice sheet surface. When surface water finds a way in to the ice sheet, it can cause the ice sheet to accelerate and slide more quickly. Credit: Matt Hoffman

With luck, our GPS and borehole instrumentation will collect data for the rest of 2011 and well into 2012.  Together, the data from the project will provide insight into how and why the ice sheet moves the way it does during the summer season. This is important because one of the major goals of the ice community is to better predict ice sheet changes in the coming decades and centuries. A critical part of this predictive ability is a solid understanding of how ice sheet velocity changes as the amount of melt on the ice sheet surface in the summer changes. The ROGUE project is designed to provide this insight, as well as set up a reference data set for large-scale ice modeling studies.

ROGUE: Real-time Observations of Greenland’s Under-ice Environment
The goal of the ROGUE project is to examine the nature and cause of short-term ice velocity changes near Swiss Camp, Greenland, by observing interactions between the ice sheet, the atmosphere and the bed.

Real-time Observations of Greenland's Under-ice Environment (ROGUE): Second Time’s the Charm

May 16th, 2011 by Tom Neumannn

May 15, 2011

Snowmobiles are a critical part of polar research as they allow us to travel from a central camp to sites up to 50 miles away. The team worked through strong winds and blowing snow to free four snowmobiles that became drifted over when the platform holding them collapsed. Credit: NASA/Tom Neumann

With a 50-50 chance of good weather, Matt and I headed out to Swiss Camp on Wednesday, May 4. We were lucky to get a break in the clouds and the wind that allowed the plane to land and drop us off safely with Koni and company. The weather continued to deteriorate over the rest of the day as the winds picked up and the snow started to blow.

Everyone was hard at work when we arrived, cleaning up the debris from an impressively strong storm that moved through the area in February. According to preliminary data from the weather station at Swiss Camp, the wind speed exceeded 70 mph for nine straight hours. As you might imagine, this sort of wind was hard on weather stations, Swiss Camp, and anything sticking up out of the snow.

At Swiss Camp, part of the platform next to the kitchen tent had collapsed, causing 4 snowmobiles, 3 barrels of fuel, and about 10 propane tanks to drop down into the snow where the storm quickly buried them. By the time we arrived this week, everything that had had fallen was buried by at least 6 feet of snow and ice. We joined the shoveling brigade through the blowing snow on Wednesday, and succeeded in freeing one of the snowmobiles and most of the fuel.

Tom pokes through a hole in the pit while digging for propane tanks. Credit: Nestor Rial

Removing a frozen skidoo is a team effort - all hands on deck! Credit: Nestor Rial

Tom takes a break during the digging on Wednesday. Credit: Nestor Rial

The wind died down by Thursday, and we freed the remaining snowmobiles by the end of the day.  Everyone was pretty worn out, as you might imagine.  The amazing part of it all was that Koni had all of the snowmobiles functional by the end of the day. We were left with an impressively large hole in the snow next to Swiss Camp, a lot of tired arms and wet clothes, and ready to start the work we came to do.

Thursday dawned clear and calmer, showing that we still had a substantial amount of work left to do. Credit: NASA/Matt Hoffman

ROGUE: Real-time Observations of Greenland’s Under-ice Environment
The goal of the ROGUE project is to examine the nature and cause of short-term ice velocity changes near Swiss Camp, Greenland, by observing interactions between the ice sheet, the atmosphere and the bed.

Real-time Observations of Greenland's Under-ice Environment (ROGUE): Boomerang!

May 4th, 2011 by Tom Neumann

May 3, 2011

Your trusty correspondents, Tom (left) and Matt (right), on the way to Swiss Camp! Credit: NASA

When thrown properly, a boomerang will always come back to the thrower.  (When thrown improperly, it ends up over the neighbor’s fence where a dog chews on it, and you don’t get your boomerang back, but that is another story for another day.) This afternoon, Matt and I enjoyed what is known as a boomerang – after an hour and a half flight to Swiss Camp, we weren’t able to land, and so returned to Kangerlussuaq for the night. Perhaps I’m getting ahead of myself.

The weather observations from Swiss Camp reported by Dr. Koni Steffen (who is already out at Swiss Camp, the lucky guy) revealed high winds all morning, up to 40 kts. Far too windy for the Twin Otter to safely land. Consequently, the Twin Otter went elsewhere to pick up cargo from another science group. Matt and I watched the weather carefully during the day, and tried to get some productive work done.

Around 2 p.m. local time, the report from Koni was that the winds had died down, and the weather was improving. After additional reports at 3 p.m. and 4 p.m., the pilots decided it sounded good enough to fly north and check it out. Matt and I helped the cargo crew load the plane with our remaining bags, boxes, and pipes and head north to Swiss Camp.

Loading the last of our cargo - pipes to hold our solar panels and antennas. Credit: NASA

It is a short flight, about 90 minutes. As we approached our destination, the cloud layers were low, and it was very difficult to make out any features on the surface (other than Koni’s tents!) or the horizon. Without being able to see either the surface or the horizon, the pilots can not safely land the plane. After a few passes, we turned around and headed back to Kangerlussuaq.

Tom is overcome by the excitement of flying back to Kanger, and returns to his preferred state. Credit: NASA

We’ve left the cargo in the plane with the hopes of making a second try tomorrow morning. The forecast at the moment calls for cloudy skies and snow, which is not so promising for us. Things look to improve significantly on Thursday, so we are optimistic we’ll rejoin Koni and the crew very soon!

So, dear reader, this might be our last post for a couple of days, but then again – you never know when you’ll boomerang again!

ROGUE: Real-time Observations of Greenland’s Under-ice Environment
The goal of the ROGUE project is to examine the nature and cause of short-term ice velocity changes near Swiss Camp, Greenland, by observing interactions between the ice sheet, the atmosphere and the bed.

Real-time Observations of Greenland's Under-ice Environment (ROGUE): Planes, Snowmobiles, and Helicopters

May 3rd, 2011 by Matt Hoffman

May 2, 2011

The cargo is loaded and ready to go. Credit: NASA

We have completed most of our preparations and are ready for our flight to Swiss Camp tomorrow. Today was spent tracking down our final cargo items and getting every to fit into boxes and bags – a trip to the cargo warehouse, a run to the airport to load a plane, back to the warehouse to move a bunch of big boxes, a walk back to the logistics building for a pre-field briefing, a walk into town for last minute groceries, a quick lunch of musk ox burgers, warehouse again, airport again, rinse, repeat.

A total of three flights made it out to Swiss Camp today, and the pilots worked hard to get it all done. The plane we fly in to Swiss Camp is a DeHavilland Twin Otter (DHC-6), which is a turboprop that is 52 feet long and can carry a few thousand pounds of cargo and personnel. The ones flown in Greenland are outfitted with skis over the wheels to land on the snow of the ice sheet. The cabin is 18 feet long and about 5 feet wide, and it is amazing to watch all that can be packed into that space.

On the last load of today, the first thing on the aircraft was a snowmobile, followed by two 55-gallon drums of fuel. It already seemed like the cabin must have been pretty full, but added to this were a couple of big tent bags, seven shipping cases, each nearly the size of a washing machine, and a handful of miscellaneous smaller items. Every time I was sure the cabin was packed the pilots would shift things around and then call for more. In the end, we ran out of stuff before the pilots gave up trying to pack it all in.

Tomorrow Tom and I will fly fairly light with a 10-foot-long plastic sled, a couple dozen pipes, a dozen 70-pound batteries, and our personal bags.

Tom contemplating how this big snowmobile will get up and in that little door. Credit: NASA/Matt Hoffman

Once we are established in camp, we will begin our science work. This will consist of loading our pipes, batteries, cases, and GPS receivers onto a sled tied to the snowmobile, and driving 10-30 kilometers (5-20 miles) across the snow-covered ice sheet to various spots to install the stations. We have pre-selected locations surrounding the sites where boreholes will be drilled this summer using satellite images and datasets of ice thickness and the location of lakes that form on the ice sheet surface, but the final placement will also depend on things like time, weather, and ease of access.

After about 10 days of camping at Swiss Camp, our work will shift to its final phase, when we will fly by helicopter to the picturesque town of Ilulissat and visit our final site locations from there via helicopter.

Our communication from Swiss Camp will be limited, so, dear reader, we may have to fill you in on our exploits when we return. Stay tuned for the next installment, in which the pictures are likely to be much whiter and our clothing much puffier.

Nothing keeps your head warm like giant rolls of attic insulation. Credit: NASA

ROGUE: Real-time Observations of Greenland’s Under-ice Environment
The goal of the ROGUE project is to examine the nature and cause of short-term ice velocity changes near Swiss Camp, Greenland, by observing interactions between the ice sheet, the atmosphere and the bed.