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Wow, That Was a Lot of Snow

April 25th, 2015 by Lora Koenig
Tents before the storm (left) and snow reaching near the top of our tents after two storms (right).

Tents before the storm (left) and snow reaching near the top of our tents after two storms (right).

April 24, 2015 — I believe in one of my first blog posts I mentioned that we were working in an area of high accumulation (snowfall) on the Greenland Ice Sheet. I would like to change that to an area of VERY HIGH accumulation! Actually Southeast Greenland does receive the largest amount of snowfall on the entire ice sheet. In previous years we have experienced storms dumping over a meter of snow. This year we had one of those storms bringing well over a meter of snow and then 3 hours after the first storm ended we got a second, bigger storm, pushing our 5 days snow total to nearly 3 meters of snow.

The amount of snow is best summed up by a dinner conversation in our cook tent where Olivia, being on the ice sheet for the first time, asked Clem, Josh and I, ice sheet veterans, what the biggest storm we had ever been in was like. We all responded, in unison,” this is the biggest storm we have ever been in!” While the weather was not particularly cold or windy, it just kept snowing. The low wind made it possible for us to continue science measurements through the storm in a special tent, with no floor, providing both shelter and access to the snow.

The storm hit on the day we were finishing up drilling. We drilled a 56 m borehole into the aquifer, reaching water around 19 m below the snow surface just as we expected. Drilling ice cores is a routine practice on the ice sheet and allows us to see the structure of the ice and measure the ice density; it is less dense near the surface and then compacts to ice at around 35 m in this region. Josh drilled the ice core using both a mechanical drill, called the sidewinder, in the top 19 m of dry firn and with an electrothermal drill in the water saturated firn below. Josh would drill about 1 m of core every 10 minutes and then Clem and I would weigh it, measure it, record ice layers, record the ice temperature and bag certain sections for Olivia’s hydrology measurements. Once the core was processed we took the remaining core to the kitchen tent to melt for our drinking water. (The more dense ice from deeper in the ice sheet produces more water than the less dense surface snow, so we are happy to use it for making water for the camp.)

Lora with Clem reflected in goggles holding an ice core with water bubbles.

Lora with Clem reflected in goggles holding an ice core with water bubbles.

Lora processing an ice core.

Lora processing an ice core.

While we were finishing the drilling Kip and Olivia were working out the kinks of using their equipment for the first time on an ice sheet. They worked through a few freezing issues and quickly had the first every water samples from the aquifer. They melted a piezometer into the ice sheet, inserted a tube and started pumping up water. We were all ecstatic to see the water gushing out of their tube and into their sample bottles.

Water samples from the Greenland aquifer.

Water samples from the Greenland aquifer.

As the hydrology sampling continued so did the storm. We had not received another resupply flight so we were running low on fuel, did not have a snowmobile or sled to move the drill to our next site and our additional team mates and measuring equipment had yet to arrive to complete more science. We knew we were already very delayed so we made the decision to postpone our seismic measurements until the fall. In the meantime the snow continued to fall!

By the third morning of the storm we were all sinking into the snow at least up to our thighs, if not our chest. Our tents were about 7 meters apart and it could take 5 minutes, and half your energy, to break trail between them. We often found it easiest to craw on the surface as opposed to walking. While the hydrology crew collected samples the rest of us dug out camp. We dug about every 2 hours. Even during the night we would have to get out and dig. In the end Josh moved into a tent with Kip and Clem, a tight fit, but more comfortable than digging out his smaller mountain tent all night. We also moved our fuel and generators into the cook tent and let our science gear get buried in its cargo line, marked with tall poles at either end, until the end of the storm. This reduced the area we had to shovel.

Path through the snow.

Path through the snow.

Josh relaxing after digging out the cook tent.

Josh relaxing after digging out the cook tent.

As the snow continued to fall, the winds stayed low. We were thankful for the low winds but knew after the storm the katabatic winds, outflow of cold air that gravitationally flows off the ice sheet, would kick up with a vengeance. On April 20th we woke up to light snow and no winds. The storm was over so we dug out all the cargo creating snow piles over our heads. Now we needed a Helo to bring in more science gear, and fuel, so we could keep working. The surface conditions were so soft that we could no longer operate a snowmobile even if we had one. At that point we knew we would only get one site completed this season because we really couldn’t move.

The calm was short lived. By the afternoon the Katabatic started with the furry we expected. The winds increased to 30 knots very quickly. Over the next 3 days the winds blew and moved all the snow around again. We were digging out our tent almost every hour. All we were doing was digging. Digging out the tents, digging the snow out of our pockets, goggles, gloves, everywhere!  We were tired! We made a decision to end the season once a Helo could get in since we had completed most of the measurements. Today, April 23, we finally got a Helo and all flew back to Kulusuk for a nice shower and warm meal. Tomorrow we will day trip back to remove our camp and, hopefully, let Anatoly make the first every electromagnetic resonance measurement on the aquifer.

Finally our helo arrives and sinks to its belly.

Finally our helo arrives and sinks to its belly.

“Groundwater” Study Hits the Ice Sheet

April 23rd, 2015 by Olivia Miller, University of Utah
The team on a walk to the airport to organize gear.

The team on a walk to the airport to organize gear.

Hello! This is Olivia and I’ll be writing about the hydrology work we are doing this year on the Greenland ice sheet. A few years back some scientists on our team discovered liquid water inside the ice sheet. They partnered with us to study the water in greater depth.

We think that the snow melts at the surface, percolates down through the snow and firn, and pools inside the ice. The water fills up the air space between the ice crystals, creating an aquifer inside the ice sheet that we think behaves similarly to aquifers found on land. The hydrology that we are doing this season is basically a “groundwater” hydrology study, except that in this case it is an “ice-sheet-water” hydrology study. We will try to test our ideas about how the aquifer behaves and understand what that means for the ice sheet and sea level rise more broadly.

To answer these questions, we will collect measurements of how deep the water is and how much pressure it has to determine where the water is entering and exiting the aquifer. We will test how quickly the water travels through the firn and also collect water samples. The chemistry of the water will tell us information about how long the water has been inside the ice sheet. All of this information will give us a much better idea of how the aquifer is filling up, and where the water is going, and how quickly it moves. This kind of information is important for understanding how ice sheet melt relates to sea level rise. If the aquifer is storing water for long periods of time, than it may have less of an immediate impact on sea level rise. However, what happens if it fills up and suddenly drains quickly? Or maybe it is constantly draining?

To make our measurements and collect our samples, we had to do a lot of work to modify traditional groundwater hydrology tools and instruments to work at very cold temperatures. Groundwater hydrologists often use piezometers, long pipes that have a small opening at the bottom to let water in, to access the aquifer they are investigating. To install a piezometer into the ground, you can pound it in. To install our piezometer into the ice, we have developed a piezometer with a heated tip that can melt through the hard ice layers.

Another challenge we face is that many of the samples we collect cannot freeze, and yet we expect the temperature at our field site to often be below freezing. When we collect these samples, we completely fill the sample bottle so there is no air space in the bottle. We do this so that we can analyze gasses that are dissolved in the water back in the lab. If these samples froze, the water would expand and break the bottle, ruining the sample. To prevent these samples from freezing, we have modified several coolers to be extra-insulated and to have special heaters inside them.

It has been quite the learning experience to take all of our groundwater hydrology work to such a different environment! But this is part of what makes the science exciting. We get to try something that has never been done before.

Ready, Set, Go!

April 14th, 2015 by Lynn Montgomery, University of Maryland

 

The team loads the final gear for the first flight.

The team loads the final gear for the first flight.

After many long days of waiting, we got an update yesterday that our helicopters would be down until April 16. We have had bad luck so far with delays – mechanical difficulties and bad weather. The team’s morale sunk to an all-time low with this news. We had been anxiously awaiting a call each day to tell us we were going to fly.

This morning, April 10, we got the news that we would probably not be flying because the helicopter was still not ready to go. Disappointed, we went on about our daily activities including going to the store and exploring town. When we got back, we heard exciting news. Fin, our pilot, had called saying he was on his way and to get ready for two flights today! The team sprang into action, furiously packing bags, driving to the airport, and getting camp and science gear into the final loads.

The Bell 212 helicopter landed around 2:30 p.m. We began to pack all of our things in when the pilot announced we could only take 650 kilos instead of the initial weight we had thought of 800 kilos. We had already stripped our science and camp gear down to the bare bones to fit the first weight limit. With this new cut, we had to take out even more gear within minutes. Although we had to cut down the first flight, the rest will be put on the second flight. Josh, Olivia, and Clem left successfully landed on the ice sheet.

Clem, Olivia, and Josh ready to get into the field.

Clem, Olivia, and Josh ready to get into the field.

The helicopter made good time, returning for the second flight around 4:30 pm. This time, they upped the weight limit to 900 kilos from 650 kilos for the first flight. Instead of having a weight problem, we were quickly maxing out on volume. At the end, we successfully got most of our science, camp gear, and food in plus Lora and Kip! We are so excited that the initial team has set up camp and is ready for the first night out in the field. I will go in on one of the next few flights.

Packing the gear into the second flight.

Packing the gear into the second flight.

Lora and Kip packed in and ready to go!

Lora and Kip packed in and ready to go!

Flying off to the ice sheet.

Flying off to the ice sheet.

There are two sling loads planned for the next two flights to take in the drill and the two snowmobiles plus more science gear. Anatoly will arrive soon on April 15 and Nick on April 20. We are slowly but surely getting all of our gear and scientists into the field.

Hurry up and overweight!

April 7th, 2015 by Lora Koenig
Our gear and the C-130. We were dropped off with our gear in Kulusuk by the C-130.

Our gear and the C-130. We were dropped off with our gear in Kulusuk by the C-130.

Hurry up and wait may the best way to describe our schedule lately.   You never know exactly when a plane or helicopter will be ready to take you into the field or when the weather will be good. All you can control is when you have your gear ready to go.

The C-130 dropped us off in Kulusuk, Greenland on Sunday (3/29/15) with over 13,000 pounds of science gear, snowmobiles, food and people. All the gear was loaded on 3 big pallets and fork lifted outside the airport next to a shipping container. Joe immediately started breaking down the pallets so we could start organizing the gear for the field. Monday brought a storm so we had to wait until Tuesday to sort our gear into the approximate Helicopter loads. We will be using a Bell 212 Helo to get into the field using 10 flights over 5 weeks to get the gear in and out.

Sorting the gear was difficult this year. We will be conducting five different science projects to better determine the amount of water retained in the ice in this portion of SE Greenland (you will hear about each separately in the blogs to come). We have to make sure all the gear for each helo load includes everything we need for each particular science project. For instance, we had to make sure the generator for the drill came in with the drill, not with the radar equipment; that the tool kit for the hydro gear was loaded with the hydro gear; and that the emergency and camp gear flew in on the first helo flight, and so on.

As we were moving our boxes around Lynn was diligently taking notes on which boxes were in each load and how much they weighed. Just after our morning team meeting on Wednesday (4/1/15) we put all our boxes in to a spreadsheet to calculate the total weigh for each load. I will backtrack slightly here to tell you a little about Kulusuk, Greenland. It is a beautiful town with mountain peaks rising above it and a beautiful fjord. It is a destination for the very adventurous skier and tourist. It has about 350 residences and one small grocery store. In short, this is not the place you can pick up a spare part, for say, a highly specialized ice core drill or water sampling equipment. So it is very common that we overpack. Send in a few extra spares for the “just in case” scenario and multiple rolls of duct tape.

This year we packed a few extra spares. We were overweight!!! The rest of Wednesday morning was spent on the computer moving boxes around and cutting out what we could to get our gear weight down. In the afternoon we started shifting gear around, and making the changes we had to make.

View from Kulusuk over the sea ice. The low visibility has delayed flights.

View from Kulusuk over the sea ice. The low visibility has delayed flights.

This all occurred at an accelerated rate because we were told by Air Greenland that they could move our flights to our field site earlier, to Thursday (4/2/15). We worked fast and hard to get ready to go. Wednesday night we were tired but ready! Thursday morning brought another storm so instead of heading to the field we got some much needed rest. It is now early Friday (4/3/15) morning, with OK weather. We will have breakfast and wait at the hotel for a 9 am call from the helo pilot to see if we are on the schedule for today. Hopefully we will launch for the field toady with two flights. The first will take Josh, Clem and I along with the camp gear. The second will bring Kip and Olivia and the hydrology. Fingers crossed or getting to our field site and starting the actual science soon. Fingers crossed for getting to our final destination today.

East and West: The Geography of Antarctica

November 19th, 2014 by George Hale

At first, the geography of Antarctica might seem a little confusing. From space, much of Antarctica looks featureless and white, meaning there are few features to guide you. It’s one thing to know that Pine Island Glacier is in West Antarctica, but for some it might be unclear which part of the frozen continent is which.

In the most general terms, Antarctica can be divided into three major areas: West Antarctica, East Antarctica, and the Antarctic Peninsula.

LIMA_overview_map

An overview map of Antarctica produced by the British Antarctic Survey to accompany the Landsat Image Mosaic of Antarctica, or LIMA.

The Antarctic Peninsula is probably Antarctica’s most prominent geographical feature and home to scientific stations operated by the United States, the United Kingdom, France, Australia, and other nations. This curved extension of the continent extends nearly 250 miles north of the Antarctic Circle and points toward the southern tip of South America. The Antarctic Peninsula has a number of glaciers and floating ice shelves that are changing rapidly because this region is warming faster than the rest of the continent.

Running along the length of the peninsula, and extending across the continent is a mountain chain known as the Transantarctic Mountains. In addition to supplying spectacular views, the Transantarctics serve as a sort of dividing line separating East and West Antarctica.

A view of the Transantarctic Mountains  during IceBridge's 2013 Antarctic campaign.

A view of the Transantarctic Mountains during IceBridge’s 2013 Antarctic campaign.

Although the Antarctic Ice Sheet is a continuous mass of ice, it is sometimes helpful to think of it as two separate masses. The West Antarctic and East Antarctic ice sheets are separated by the Transantarctics, with ice on the west side generally flowing toward the Western Hemisphere and ice on the east side flowing toward the eastern hemisphere. (In both cases, this is actually flowing north…away from the South Pole.)

East Antarctica is considerably larger than West Antarctica, and its ice sheet is thick – nearly three miles (five kilometers) in some regions . The ice surface of East Antarctica is high and home to some of the coldest and driest condition on Earth.

The East Antarctic Ice Sheet is considered to be more stable than the West Antarctic. One reason is the shape and elevation of bedrock beneath the ice. Heavy masses of ice push down on bedrock, depressing some areas below mean sea level. If those low-lying areas happen to be near the edge of the ice sheet — which is the case in much of West Antarctica — then ocean water can make its way under the ice, speeding up glacier flow.

This is one of the reasons that, while both portions of the ice sheet are losing mass, West Antarctica is moving much faster. Recent studies of West Antarctica found that many of its fast-moving glaciers are in an irreversible decline.

sea ice shadow

Shadow of the NASA DC-8 on sea ice in the Weddell Sea. Credit: NASA / Jim Yungel

Antarctica is surrounded on all sides by the Southern Ocean. During the winter, ocean water freezes, forming a layer of sea ice of roughly the same area as the Antarctic continent. In recent years, sea ice around the continent has been increasing.

The ocean around Antarctica is divided into several seas. Starting to the right of the Antarctic Peninsula on the map is the Weddell Sea, which extends to Cape Norvegia, a small point of land jutting off of East Antarctica. Moving clockwise we go around the East Antarctic coast all the way to the Ross Sea, south of New Zealand. Next comes the Amundsen Sea, where large West Antarctic glaciers like Pine Island and Thwaites drain. We complete our trip around Antarctica by coming to the Bellingshausen Sea, to the left of the Antarctic Peninsula.

For maps of Antarctica, including some that use imagery from the Landsat satellite, visit:
http://lima.usgs.gov/download.php

To use an interactive Antarctic atlas, visit:
http://lima.usgs.gov/antarctic_research_atlas

Notes from the Field