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NASA in Alaska 2014: Charting MABEL’s course

August 1st, 2014 by Kate Ramsayer

For more than 65 hours this month, NASA’s high-altitude ER-2 aircraft flew from Fairbanks over melting sea ice, glaciers, forests, permafrost, lakes, volcanoes and more. It zigged and zagged over the Beaufort Sea, and soared straight over the Bagley Ice Field.

The goal: to use a laser altimeter called MABEL to take elevation measurements over specific points and paths of land, sea and ice. To hit these marks, scientists and pilots painstakingly designed and refined flight routes. And then they adjusted those routes again to capture cloud-free views – a tricky proposition in a giant state with mountains creating complex weather systems.

A camera on the MABEL instrument captured shots of cracked sea ice, dotted with melt ponds, during a flight to the North Pole. (Credit: NASA)

A camera on the MABEL instrument captured pictures of cracked sea ice, dotted with melt ponds, during a flight to the North Pole. (Credit: NASA)

“We have targets to the north, targets to the south, and mountain ranges blocking both,” said Kelly Brunt, a research scientist at NASA’s Goddard Space Flight Center who was MABEL’s science flight planner.

Scientists studying forests, glaciers, water and more are using MABEL data to develop software programs for the upcoming ICESat-2 satellite mission, and sent Brunt lists of what they would like to be included in the Alaska campaign.

“We get everybody’s input, and start to put it on a map,” she said. She drafts routes with targets in similar weather patterns, so that if one is clear the others are likely to be as well. However, often targets are removed from a route, based on the weather assessment from the morning of the flight. During the deployment, routes are also constructed to target specific sites that were missed during previous flights for either weather or aircraft reasons. Lots of the work goes into straightening the flight line, Brunt said, since when the aircraft banks at 65,000 feet, the laser instruments swivel off their ground track and the scientists can lose miles worth of measurements.

The MABEL campaign's July 24 flight route covered glaciers, ice fields, forests, the Gulf of Alaska and more. (Credit: NASA)

The MABEL campaign’s July 24 flight route covered glaciers, ice fields, forests, the Gulf of Alaska and more. (Credit: NASA)

One flight to measure sea ice was pretty direct – it took the pilot straight to the North Pole over one longitude line, circled around and came back on another. A second route involved a zig-zag pattern over the Arctic. But both routes were designed to capture a range of summer ice conditions, including melt ponds, large stretches of open water, and small openings in the sea ice, known as leads.

Flights over Alaska itself were often mapped to pass over glaciers, lakes, ocean moorings or even tide gauges that others have measured before, to compare with the data MABEL collected. Students from the Juneau Icefield Research Program (JIRP) assisted MABEL researchers by providing ground-based GPS validation for a mission that flew over the upper Taku Glacier, close to a JIRP camp. And the MABEL team collaborated with NASA Goddard scientists flying a different instrument, called Goddard’s LiDAR, Hyperspectral and Thermal (G-LiHT) Airborne Imager – the two campaigns flew some of the same paths over interior Alaskan forests.

NASA ER-2 pilot Denis Steele, in a pressurized flight suit, before a July 16 flight over Alaska's glaciers. (Credit: Kate Ramsayer/NASA)

NASA ER-2 pilot Denis Steele, in a pressurized flight suit, before a July 16 flight over Alaska’s glaciers. (Credit: Kate Ramsayer/NASA)

From Fairbanks, Brunt worked with the campaign’s two pilots, Tim Williams and Denis Steele, to ensure the routes would work with the ER-2’s capabilities; and with weather forecasters to determine where to best focus efforts the following day.

In all, the campaign flew 7 flights out of Fairbanks. And today, the ER-2 – with MABEL aboard – flies back to California, collecting even more data about the elevation of the landscape along the way.

NASA in Alaska 2014: A Frozen Fieldtrip from Fairbanks

July 21st, 2014 by Kate Ramsayer

Not content with looking at ice from the air, on their day off from flying last week the MABEL and ER-2 team decided to look at ice underground. About a dozen of us went to visit the Permafrost Tunnel Research Facility, a U.S. Army site north of Fairbanks, Alaska, where the crew is based for a summer campaign.

Cut into a forested bluff, with just a red, shed-like structure leading into the hillside, the Permafrost Tunnel doesn’t look like much from the outside. But inside, there are thousands of years of sediments, plants, and ice-age mammal bones frozen in the wall.

The Permafrost Tunnel Research Facility, dug in the mid-1960s, allows scientists a three-dimensional look at frozen ground. (Credit: Kate Ramsayer/NASA

The Permafrost Tunnel Research Facility, dug in the mid-1960s, allows scientists a three-dimensional look at frozen ground. (Credit: Kate Ramsayer/NASA

It’s hard to say what you notice first: the cold or the smell. The cold – it’s kept at a brisk negative 3 degrees Celsius (26.6 degrees Fahrenheit) – is now maintained during the summer with a chiller system. Opening and closing the tunnel door for decades, along with warming outside air temperatures, would otherwise melt the permafrost. The smell, explained our guide Tom Douglas, a geophysicist with the Army who conducts research in the tunnel, is from all the decaying organic material in the walls – plant and animal matter – coming into contact with the air and oxidizing.

A mammal bone sticks out of the wall of the Permafrost Tunnel. (Credit: Kate Ramsayer/NASA)

A mammal bone sticks out of the wall of the Permafrost Tunnel. (Credit: Kate Ramsayer/NASA)

Permafrost is ground that stays frozen for more than two years – including the summer months. In cold areas like Central and Northern Alaska, permafrost can build up over millennia, creating a kind of time capsule. In the Permafrost Tunnel, tiny roots of grasses and trees that lived 20,000 to 30,000 years ago drip from the ceiling.

“They’re preserved,” Douglas said. “They tend to be freeze-dried a little bit.” A giant, and surprisingly heavy, mammoth femur was found in the tunnel; horns of bison-like creatures still stick out of the wall. In a wedge of ice cutting through the permafrost, Douglas explained, researchers had melted a sample and found microscopic organisms that hadn’t been previously described.

The tunnel turned up a variety of ice-aged mammal bones - including the giant leg bone of a mammoth. (Credit: Kate Ramsayer/NASA)

The tunnel turned up a variety of ice-aged mammal bones – including the giant leg bone of a mammoth. (Credit: Kate Ramsayer/NASA)

The ice wedges themselves are some of the tunnel’s most impressive. They’re created when the surface of the ground freezes and contracts in the winter, creating cracks in the ground. When spring comes, meltwater fills in those cracks, freezing when it reaches the permafrost layer. The next winter, when the ground cracks again, it often does so along the weak areas where it cracked before – and then another round of spring meltwater freezes, pushing the ground apart even further. Over the years, a lattice-work of wedges forms.

Ice wedges form over centuries, creating polygonal patterns in the permafrost. (Credit: Kate Ramsayer/NASA)

Ice wedges form over centuries, creating polygonal patterns in the permafrost. (Credit: Kate Ramsayer/NASA)

The tunnel was dug in the mid-1960s, Douglas said, and has been used for a variety of research. One question he investigates is how well different radars and surveying equipment can identify underlying permafrost, which is key for building and road construction – you don’t want to build on ground that could thaw.

The necessity for that kind of research was evident on the way back to Fairbanks – the road dips along the hillside, thanks to the dynamic ground underneath.

Greenland Aquifer Expedition: On The Ice Sheet!

April 18th, 2014 by Maria-Jose Viñas

By Rick Forster

Our team finally made it to the ice sheet on April 8, after being delayed for almost two weeks due a series of storms. That day, we awoke to patches of blue sky over the village of Tasiilaq and were eager to get to the heliport for our scheduled 11:40 AM flight to the ice sheet. Lingering clouds over the ice sheet delayed our departure about three hours.

The village of Tasiilaq on the day of our flight to the ice sheet in SE Greenland where the Air Greenland B-212 helicopter is based.  (Credit: Rick Foster.)

The village of Tasiilaq on the day of our flight to the ice sheet in SE Greenland where the Air Greenland B-212 helicopter is based. (Credit: Rick Forster.)

Once we saw the Air Greenland helicopter returning from its last trip to the local settlements for the day, we knew our flight was next. The trip to our research site on the ice sheet takes about 30 minutes.

The Air Greenland B-212 helicopter landing in Tasiilaq. (credit: Rick Forster.)

The Air Greenland B-212 helicopter landing in Tasiilaq. (credit: Rick Forster.)

The two-week weather delay meant I had to return to the University of Utah while Clem and Ludo would stay on the ice sheet for about 10 days to gather data and perform experiments on the Greenland aquifer. It was a hard decision to make, but I had commitments and if I stayed with the team on the ice sheet, we would all have to leave before all the science could be completed. Ludo and Clem’s schedules were more flexible so they will be able to extend their trip to spend extra time on the ice. I went with the team to the ice sheet to help unload the camp gear from the helicopter at the research site.

From left to right: Clément Miège, Ludovic Brucker, and Rick Forster happy to be finally boarding the helicopter for the flight to the ice sheet. (Credit: Rick Forster.)

From left to right: Clément Miège, Ludovic Brucker, and Rick Forster happy to be finally boarding the helicopter for the flight to the ice sheet. (Credit: Rick Forster.)

The flight to the site was spectacular, going over sea ice chocked fjords and outlet glaciers draining the ice sheet.

An outlet glacier draining the Greenland ice sheet into an ice covered fjord. The individual rough blocks of ice within the smooth surface of the frozen fjord are icebergs that calved off the glacier last summer and are now trapped in the winter fjord ice. (Credit: Rick Forster.)

An outlet glacier draining the Greenland ice sheet into an ice covered fjord. The individual rough blocks of ice within the smooth surface of the frozen fjord are icebergs that calved off the glacier last summer and are now trapped in the winter fjord ice. (Credit: Rick Forster.)

Once at the research site, our team, including the pilot and flight engineer, quickly unloaded the cargo from the helicopter. The heaviest gear could be left closer to the helicopter, while the lighter pieces needed to be dragged farther away and held down by Ludo and Clem to keep them from being blown away from the winds generated by the helicopter taking off. The ice sheet surface was smooth and soft with knee-deep powder, great for skiing but not so good for moving cargo and setting up camp.

Clem, Ludo, and the science and camp cargo waiting for the helicopter to take off. (Credit: Rick Forster.)

Clem, Ludo, and the science and camp cargo waiting for the helicopter to take off. (Credit: Rick Forster.)

Clem and Ludo will spend the next week and half gathering additional data on the Greenland aquifer from a variety of ice penetrating radar systems and installing an automated weather station for our colleagues at Institute for Marine and Atmospheric research Utrecht.

Greenland Aquifer Expedition: Bonjour from Kulusuk!

April 4th, 2014 by Maria-Jose Viñas

By Clément Miège

It might be hard to believe but yes, we are still in town! We have been delayed for a full week now, every day getting ready for a possible flight the next day, and every morning, we get the same message: “Unfortunately, there will be no flight to the ice cap today due to weather and bad visibility with low clouds, but tomorrow looks more promising.” Oh, no! Even if it is fully justified, it is always a bit disappointing the moment you hear that, but I think our team has a good experience already with this kind of delay and we are able to switch quite easily and still be happy and optimistic for a flight the next day.

The main helping factor that puts us back in a good mood comes from the weather forecast. Indeed, every day we are able to see a clear-sky window that makes us think that we will be able to fly the next day. Sometimes, this weather window can be very tiny, but it is always there! Good spirits!

Tomorrow, again, it looks great, with a weather window in the afternoon (Forecast provided by the Danish Meteorological Institute .)

Tomorrow, again, it looks great, with a weather window in the afternoon (Forecast provided by the Danish Meteorological Institute .)

When you look at long-trend forecasts (beyond the following 48 hours), the weather is changing a lot in short spans of time. Often, there are significant changes from one forecast to its updated version a couple of hours later. For example, a 5-day storm, with heavy precipitation, appears in the forecast, but then it it is removed from the next update. So our moods shift quite a bit. For even longer trends, it becomes a different story. Rick shared with Ludo and me his experience with the so-called “Canadian Forecast”. It consists of making the last 5-6 days of a 14-day weather forecast always be nice and sunny, to keep people happy through the winter so they can anticipate the end of it. We can verify this “happy weather trend” in Greenland with our own Danish Forecast — the five last days of this forecast are always sunny. We are keeping a record of the forecast since we arrived two weeks ago, and we can say this is a regular pattern.

After checking weather forecast here, our daily duties are not done yet! Next, we take a look at the data from a weather station that is currently in the field, in our future camp site. We dropped the weather station as part of our cargo last week, but we did not have time to set it up. It is however transmitting data and our IMAU colleagues gave us access to the transmitted data. Unfortunately, the signal for diurnal temperature is getting weak, it’s almost nonexistent anymore, which means that the weather station is getting buried. More and more snow will need to be removed to access our equipment when we will get to camp (maybe tomorrow?) Next, we take a look at the Kulusuk airport’s flight schedule for the day. We can see for example that the Tiniteqilaaq flight is canceled (“aflyst”, in Danish) and that the Isortoq flight is delayed. Then, we do the same thing for the Tasiilaq heliport schedule and then we speculate (while drinking our coffee) where our flight fits in this schedule. We are getting quite good at this exercise! Our flight never fits and we are always rescheduled. But there are some events that are still out of our control. Three days ago, a domestic conflict in Kuummiut required the police Marshall to solve it. Since the Marshall is based in Tasiilaq, the helicopter had to fly him there. That day we had woken up at 5:30 am for a flight scheduled to leave at 7:05, which got rescheduled to 11 am, and after three additional hours waiting at the airport, it eventually became a cancelled flight. Needless to say, the helicopter never made it to the Kulusuk airport. We simply went back to the hotel in the pouring rain. As Ludo likes to say: “This is again craptastic; good times!”

Sunday (March 30) was a beautiful day though, but we were not on the flight schedule — the pilots had to catch up with the Saturday flights had been cancelled. We took advantage of the nice weather to further test our field equipment. As I mentioned in an earlier post we will be testing a low-frequency radar system in the aquifer region on the ice sheet. Laurent Mingo at Blue System, who develops the IceRadar is letting us test a beta version of one of his radar systems. The IceRadar is currently used by many research groups on alpine glaciers, ice caps and ice islands. As such, it has been deployed in many regions of the world (Yukon, Rocky Mountains, Himalaya, Bhutan, Iceland, the Andes, the European Alps…) to perform ice thickness measurements and bed mapping, but also to look at the glacier englacial properties. I believe this is the first trip for the IceRadar to the Greenland ice sheet. So we are quite honored to have this system with us to try it over the aquifer.

Setting up the IceRadar for the first time in Greenland, with the 5 MHz antennas. The lower the frequency used for the radar, the longer the antenna has to be. For a 5MHz system, the antenna length is 20 meters (about 70 feet), and there are two of them (receiving and transmitting). (Credit: Rick Foster)

Setting up the IceRadar for the first time in Greenland, with the 5 MHz antennas. The lower the frequency used for the radar, the longer the antenna has to be. For a 5MHz system, the antenna length is 20 meters (about 70 feet), and there are two of them (receiving and transmitting). (Credit: Rick Foster)

After the setup, we try our radar going from the seasonal snowpack to the relatively thin sea ice – that gives us important changes in terms of dielectric constant, which look quite obvious in the radar profile. The system total length is about 50 meters (164 feet), so no sharp turns are allowed! (Photo credit: Rick Foster.)

After the setup, we try our radar going from the seasonal snowpack to the relatively thin sea ice – that gives us important changes in terms of dielectric constant, which look quite obvious in the radar profile. The system total length is about 50 meters (164 feet), so no sharp turns are allowed! (Photo credit: Rick Foster.)

Getting the 40MHz IceRadar ready, you can see the difference of the antenna size -- this is definitely easier to turn. (Photo credit: Rick Foster)

Getting the 40MHz IceRadar ready, you can see the difference of the antenna size — this is definitely easier to turn. (Photo credit: Rick Foster)

Rick watches Ludo and me maneuvering the IceRadar from the hotel. A new (feline) friend is also observing us, probably wondering what we are doing here! (Credit: Rick Foster.)

Rick watches Ludo and me maneuvering the IceRadar from the hotel. A new (feline) friend is also observing us, probably wondering what we are doing here! (Credit: Rick Foster.)

At the end of the day we have great news: the IceRadar is working well at the two frequencies tested, which is really promising toward our ice sheet measurements. YAY!

Finally, the hotel still does not have running water. As Ludo mentioned in an earlier blog post, the heating element in the water pipe supply line that prevents the water from freezing broke. And the road to get to the lake with fresh water is still being plowed, but the bad weather and drifting snow prevent the plow truck from making much progress. We are getting used to showering with a water bucket and becoming more and more efficient at conserving water.

Transferring water into bottles for drinking (Photo credit: Rick Foster.)

Transferring water into bottles for drinking (Photo credit: Rick Foster.)

Without water at the hotel, we are even more motivated for going to the ice sheet since we know we will not be missing a good hot shower anyway.

Our team has a really good feeling for tomorrow, so let’s hope for a “go” and keep our fingers crossed!

Cheers, Clément on the behalf of the aquifer team.

Greenland Aquifer Expedition: If you can’t get to the field, the field will come to you

April 3rd, 2014 by Maria-Jose Viñas

By Ludovic Brucker

 Kulusuk, 31 March 2014 — When I started writing this post, my opening was: Greetings from (still) white-out and windy Kulusuk :(

Updated opening sentence: Greetings from now rainy Kulusuk :( :(

The nice thing about weather forecasts is that they change all the time, so you never get bored watching them. The bad thing about weather forecasts is that they change all the time. What we have been experiencing over the past days was bizarre. We had a storm with sustained high winds and some gusts. We then had temperatures high enough to work outside without a jacket. We also had calm periods alternating every half hour or so with sustained gusting events, so intense that it wasn’t advisable to get near the windows. Now, it is raining.

Since everything was ready for days, we sat and watched the rain.

Since everything was ready for days, we sat and watched the rain.

We spent the last couple of days patiently waiting a phone call or an email. During these days, we made sure to be able to arrive at the airport ready for a put-in flight within an hour notice, if necessary. So far, a good weather window coinciding with availability of the B-212 helicopter and its crew has not happened. We like to think that we will have a flight tomorrow morning. This might happen. As Daniel L. Reardon said: “In the long run the pessimist may be proven right, but the optimist has a better time on the trip.” We are optimists, despite the weather teaching us to be realists.

In the mean time, at the hotel… there is no (liquid) water available anymore since Friday. The pipes bringing the water from a nearby lake are frozen, due to an issue with the pipes’ insulation. This sounds typical here, but usually the hotel’s water tank can get refilled with a winter water truck (please, don’t ask for details, I tried to understand but couldn’t figure this story out completely). But now the road (the only one road) is buried under more than 2 meters of drifted snow. Hence, the winter water truck cannot resupply the hotel’s water tank. We were preparing to melt snow. As Rick thoughtfully mentioned it at breakfast this morning: “if you can’t get to the field, the field will come to you” © Rick Forster. However, the hotel employees went to pick up some big jugs of water for drinking, cooking and even showering at the village! Our record is less than 2 liters used per shower. The colder the water, the less you use of it.

Getting ready for a last shower before departing.

Getting ready for a last shower before departing.

Today, we moved the rest of our cargo up at the airport, including our personal bags. We are really hoping to go to the field soon (that is tomorrow early morning). Keep your fingers crossed for us! Signed: Ludo, one of the three optimists.

Notes from the Field