Several countries are conducting many kinds of observations on the Greenland Ice Sheet (GrIS) to understand the complicate processes of losing mass of the GrIS under Global Warming. Japan had set an observation site on the northwestern GrIS on June in 2012 by collaborative expedition with Meteorological Research Institute, National Institute of Polar Research, Hokkaido University and so on.
The observation site is called as "SIGMA-A site", and meteorological and glaciological observations had been conducted in 2012-14 and installed an Auto Weather Station (AWS) at SIGMA-A in 2012. The meteorological data measured at SIGMA-A have been sent to Japan everyday by a satellite since 2012. Because SIMGA-A is within accumulation zone of the GrIS, the AWS was buried by snow year by year. To keep the AWS, we have to extend the poles of the AWS periodically. One of our missions of this expedition is an extending of the poles of the AWS.
We flied from Qaanaaq village to SIGMA-A site using a charter helicopter of Airgreenland. We transported 1 ton of equipment and 6 members of the expedition by 2 flights, made tents on the Ice Sheet and started the life of the research on the ice. Air temperature at SIGMA-A was –10°C. It was comfortable for us. At the 3rd day of the camp, we tried to re-build the AWS. We made a 4m-long tripod with aluminum poles and hung a chain block at the top of the tripod. We pulled out the main pole of the AWS from joint parts nearby snow surface, and laid down the divided upper part of the main pole. After we replaced several sensors, we connected an extension pole of the main pole at the bottom of the lying AWS, and raised the divided upper part of the main pole by hand near the divided bottom part of the main AWS. We hoisted the upper part of the main poles with a chain block, and joint the upper part to the bottom part. We fixed stays immediately.
We were only 6 persons and did not have any heavy machines on the ice. We had discussed and confirmed the process of those over and over. I felt relieved when AWS had sent correct meteorological data to Japan finally.
This expedition was conducted by collaborative studies with ArCS, SIGMA-II project and The experimental research fund for global environment conservation, the ministry of the environment Japan.
Sumito Matoba (Hokkaido University / A member of Theme 2)
The members of the expedition rolling up their sleeves just before maintenance of the AWS at SIGMA-A
Auto Weather Station at SIGMA-A site