Saturday, March 31, 2012

Waking up in qetortaq - we needed to be out before nine so that school could go into session - we broke up into two teams. Jeremy and Stefan went off to the Tracy Glacier to do more CTD work while the rest of us went out just around the corner from the village to deploy an Ice Mass Balance and GPS buoys. 

Drilling for the Ice Mass Balance Buoy Deployment
The Ice Mass Balance Buoy measures the growth and melt of sea ice over a period of time. This helps us understand the processes that control the melt of sea ice. On this expedition we are using these buoys to monitor the melt processes near the glacier. It seems somewhat counterintuitive but the sea ice actually grows in thickness just before it melts. What happens is that the sea water which is at -1.5 C interacts with the melt water from the glacier which is at 0 C. As fresh water is more buoyant it floats onto the underside of the ice where it might freeze. So, just before the melt cycle the ice might grow thicker. 

Using these buoys we are also getting a temperature profile through the ice which tells us how the heat is being transferred from the atmosphere to the ocean. 

The plane, the runway and the people 
The GPS buoys are specialized GPS receivers capable of measuring the latitude, longitude and height to a few centimeters. They allow us to look at the effects of tidal changes on the sea ice. They are also used to monitor the small scale movements of the ice that are not visible to the naked eye that could influence the breakup of the pack when the ice melts. 

After deploying the buoys we dropped Susanne and Shane back at the village and continued on to a small set of grounded icebergs right outside the village. Given all our previous experiences we went to some lengths to protect our computers from the cold. Peter had slipped his laptop inside his overall so that it would remain warm courtesy his body heat. I had all the batteries to run the plan inside my overalls. In getting to the site we had shovel a small runway for the plane.  Lars and Christian, the two hunters who were with us, took turns with me in shoveling off the four inches of snow that covered the area. They are both near sixty years of age but went to it with such gusto that they made short work of it. 

Peter flew a nice mission over the icebergs although the cameras failed to take any pictures. 
He wound up landing the plane in the snow where it did a single cartwheel but was not damaged. 
Carrying water home

When we got back to the village, Shane and Peter took off on a walk and wound up being invited to 
a party at a house where they feasted on walrus, seal, fish and chocolate cake. In the evening six of us and two of the hunters shared a house. Lars and Christian had both carried back large lumps of ice from the grounded icebergs which they broke up and dumped into our water containers. We were all somewhat dreading the long trek back and suggested that we get an early start but the hunters insisted on a mellow ten o'clock start and just urged us to hydrate for the return. 

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