Ice, Ocean, and Faxe Kondi

Hi everyone,

I returned from Greenland yesterday, and thought I would give a little summary on how our three week trip to Ilulissat went.

On June 19, David (my advisor), Denise (David's wife and our amazing chef), Carl (a student of David's who recently finished his PhD), and I left JFK Airport bound for Reykjavik, Iceland. Reykjavik was just an overnight stopover on the way to our final desination: Ilulissat. Ilulissat is a town of 5000 people on the west coast of Greenland and is located right beside Jakobshavn glacier, the world's fastest flowing and most productive glacier. The glacier flows into Jakobshavn fjord at a rate of 10km/yr, and continually calves off large icebergs, which flow down the fjord and eventually into the ocean. About 10% of the ice over Greenland drains into the ocean through this fjord, making it a strong indicator of how the ice sheet is changing in general. Scientists have found that Greenland is losing ice at a rate of about 200 Gigatons/year (which is about 200 cubic kilometers worth of ice each year).

The "Ice Front" is the spot where the ice sheet ends, and the icebergs start to break off. The image below shows the ice front position over the past 150 years. Notice the huge retreat that happened after 2001. We believe that changes in the local ocean properties are driving these changes in the glacier, and our current project involves observing the ocean inside and outside of the fjord, as well as making numerical computer models to study the ocean circulation and the ice evolution in the fjord.

In the past 15 years the ocean water near Jakobshavn has changed considerably, and these changes may be attributable to global warming. In some of his earlier work, David found that in 1997 a large body of warm (3 degree), salty water from the North Atlantic ocean appeared on the west coast of Greenland, and has remained there since. Before this, the warmest water was 2 degrees and considerably fresher. This warmer water represents huge potential for increased glacier melt.

4 years ago, David and Carl started taking measurements in and around Jakobshavn fjord. I'm going to leave the results of that out for now, since I don't want to steal any of the surprise from Carl's next paper! One thing I can say, though, is that the warm Atlantic water has travelled all the way into the fjord and is likely increasing the melt rate and the calving frequency at the ice front.

The first part of our trip was a seven day boat cruise to study the ocean near the fjord mouth, and also in Disko bay, the large bay around Ilulissat. David has a container at the Ilulissat airport and we spent our first few days getting all of our equipment ready. We also found time to enjoy some expensive Greenlandic beer (88 kroner, about $17 per pint), eat the Tom Yum Pizza (a local specialty), do some night hiking, and form our very own rock band, the Qeqertarrsuaqs (see below). We also adopted new Greenlandic personas. I was given the name Nanoq, meaning Polar Bear!

We boarded our ship, the Porsild, on a Friday afternoon and headed to the mouth of the fjord. I had never spent more than a day on a ship before, so spending a week straight on a boat was definitely unchartered territory for me. Not showering for a week was also unchartered territory that, unfortunately, we would all explore. The ship was fairly small, but comfortable and clean. The captain's name was Fari, and there were two crewmen, Erik, and Soren. Besides a few words, they didn't speak English, and we literally spoke zero Danish or Greenlandic. We were forced to get creative with our gestures and hand motions but we managed to get by just fine. We had 4 bunks in a little v-shaped room in the hull of the ship, and also had a small kitchen, bathroom, and table. Even by New York standards it was cozy down there.

The bulk of our work on the ship was doing CTD (conductivity, temperature, depth) measurements. From conductivity you can determine the salinity of the seawater. In the past, Carl and David have done 12 CTD stations. This year, we extended our measurements, doing 66 stations over a much larger spatial scale. We found some surprisingly warm water in Disko Bay, which will be interesting to track in future years. Also, our Disko bay measurements hinted at an ocean circulation which we hadn't expected to see.

The scenery on the boat was incredible. For the first and last days, we were navigating through a minefield of beautiful icebergs. At one point we hit an iceberg extremely hard. I was in the bathroom at the time and saw the white berg drift past us with a big red paint streak from the boat. Erik leaned over the front to check for leaks and luckily didn't find any (see below!). Further away from Jakobshavn, the ice cover was less intense and we were basically in clear ocean. There was one rough day which was challenging for my stomach, but for the most part the weather was great. The temperatures were between 5-10 C most of the time and we hardly had any rain. Also, we had 24 hour sunlight for our entire trip! Below is a Greenlandic sunset, which is as dark as it got.

Another success on the ocean cruise was our first ever mooring recovery. The mooring is basically a CTD that sits at the bottom of the ocean for a year collecting data. We have had a lot of trouble recovering our moorings in the past because the local fishermen catch them in their nets and then hold them ransom. The going ransom rate is $500, but typically it requires some negotiation to get them down to that price. This year, one of our moorings managed to evade the nets, and we sent an acoustic signal to it, which caused it to release itself from the anchor and float back to the ocean surface. We spent about half an hour looking for it because it was surrounded by icebergs, but we eventually spotted it! The data off the mooring looks great, and there are some interesting patterns that we are working on explaining.

After our boat trip, the next thing we did was take a trip out to our weather station, which is located at the closest piece of land to the ice front, about 60km inland from the coast. To get to the weather station, we have to get dropped off by helicopter, which is an awesome experience in itself. I got to sit in the cockpit on the way there! The view from the weather station is spectacular, looking out over the glacier and the fjord. We spent two days working on our weather station, which measures temperature, pressure, wind speed and direction, rainfall, snow accumulation, and humidity. Also, the weather station has cameras which take a photo of the ice front every hour and then send the photo back to NYU in real time. The whole station is powered by wind and solar energy, so it is completely self-sufficient.

Also, on our flight to the weather station, we deployed three Gonzak devices on the glacier, which are GPS devices in a black box. The idea of the Gonzaks is to the track the velocity at which the glacier is moving and also to compute the strain rates (how fast two points move relative to one another) in the glacier.

We camped at the weather station, which was slightly uncomfortable because we were basically sleeping on rock, but I think we were tired enough that it really didn't matter. We also celebrated Canada Day while we were there with a BBQ. The helicopter was due to pick us up on Monday morning, but some serious rain and fog hit on Sunday morning and didn't let up until late in the afternoon on Monday. The weather was pretty miserable for those two days and when we weren't working we basically spent our time hiding out in our tents trying to stay warm on dry. When the rain stopped Monday, Carl, Bror (a local guy that we hired to protect us from polar bears. Don't worry, he didn't have any work to do on this trip) and I took a great hike down to the glacier. The landscape is really rugged near the weather station and makes for really fun hiking. On Tuesday morning the fog cleared completely, and it was perfect flying conditions at the weather station. Unfortunately, Ilulissat was still fogged in, and we had to wait another 5 hours until the helicopter could come rescue us. It was a huge relief when I heard the sound of the rotor blades getting closer to us!

The next day, we got back in the helicopter again and started the most exciting day of the trip. We had two things to do: rescue the gonzaks from the glacier and deploy 12 xCTD probes (the x stands for expendable) in the fjord. The fjord is extremely jammed up with ice, making it impossible to get in with a ship to take measurements. An xCTD is a probe that we throw from the helicopter into patches of open water in the fjord. We basically fly around until we find a spot with open water and then the pilot hovers overtop of it while we throw the probe in. We hover there for about 5 minutes as the probe sinks 800m to the bottom of the fjord. There is a very thin copper wire connected to the top of the probe and the data comes back up that wire as the probe sinks to the bottom. We can see the data appearing in real time on a laptop in the helicopter. When the probe hits the bottom, we simply break the wire and then move onto the next spot. I was the thrower and David was the computer operator. It was so much fun! I was wearing a video camera on my head for part of that day, and I made a video below with some of the footage.


Ilulissat 2012 from Mitch Bushuk on Vimeo.

We had one free day at the end of our trip and Carl and I took advantage of it by taking a great hike. The hiking is really beautiful around Ilulissat. On our hike, we saw a rock where someone had etched there name into the lichen growing on it. It was dated 1954 and was still perfectly legible!

Tomorrow Carl and I are off to Newfoundland to find an iceberg! More updates on that later :)