Today our pilots (Troy and Derek) gave us the all clear to fly and begin our experiment for real, setting out the corner reflectors and transect lines. Just as good news for us was that yesterday the Henriette and the second Twin Otter, which had been stuck in Greenland, arrived bringing with them the radar that we will use on the ground to help test how CryoSat-2 sees the snow and ice from space. (Rosie and I were very pleased to see it get here, strange how you become attached to these things – We wont like it so much when we are dragging it over the snow and ice in -30°C)
So after checking the weather forecast again with Troy we went down to the airfield, loaded up the Twin Otter and were airborne by about 9.00 a.m (the top image is us loading up the Twin Otter). Due to the early start I managed to sleep all the way there and woke up when I felt the plane losing altitude. Troy and Derek were circling around the ice looking for a safe place to land, where the ice was thick enough to support our weight without us ending up in the ocean beneath. After a few low passes at about 15m to scout out the makeshift runway we landed pretty smoothly. You can see the landing in the video above. After we landed they taxied around for a bit to compress the snow and make a runway for us to take off from. This was my first ‘unseen’ (i.e. no one has ever been there before and one has test how thick the ice is) landing on sea ice and it was pretty exciting.
Photo: One end of our site marked by orange material and bin bags. You can just see the corner reflector behind the flag, which we use to line the site up).
Our first site was at 85.6° N 69.8° W, the furthest north I have ever been and will probably ever get to. The conditions were great around -25°C and not very windy, we set up the corner reflectors and marked their locations with large coloured sheets of material and bin bags full on snow, so Henriette and the other Twin Otter could see them from the air. Malcolm then used a satellite phone to call back to the base and tell the Henriette that they could leave to overfly our ground site, taking measurements with their airborne radar and laser. We also measured the ice we landed on – it was about 1.80 m thick (below is 100s of km of ocean).
Photo: Christian drilling through the ice to see how thick it was.
We then headed south again to 83.3°N 62°W to set up our second site. It was colder and windier here, but the set up went well again and the most important thing, we saw that the snow cover at the two sites appears to be different. This is important for our experiment as we want to see if the radar sees through the snow in the same way when the snow has different properties.
We only needed about 30 m of runway to take off from the second site as we were lighter after leaving the corner reflectors on the ice and we made it back to Alert for dinner. Rosie, Seymour and I have spent the rest of the evening making sure that our ground radar is working and as I’m typing this in the common room, Malcolm is using the data from the GPS buoys we put with the corner reflectors to track where they are moving as the ice moves.
P.S. I’m very tired while writting this so sorry if the grammer isn’t great!