Project Report

The ArCS II Cryosphere Program (Sub-1) Snow/Ice and Climate Team stayed at the SIGMA-A site, northwest Greenland ice sheet from 21 to 27 June 2023 to carry out research activities for the project. Originally, this expedition at the SIGMA-A site was planned in 2021; however, it was impossible to perform during the past 2 years due to COVID-19. In this year, we did our best to perform the expedition. For the access to/from the site, the Twin Otter by Kenn Borek Air (Canada) was used (Fig. 1).

During the period, the research team installed a new Automatic Weather Station (AWS) successfully (Fig. 2).

In addition, the research team conducted in-situ glaciological measurements, GPS measurements, and drone measurements. The AWS measures surface pressure, air temperature/relative humidity/wind speed/wind direction at 3 and 6 m above the snow surface, snow temperature at 3 difference depths, and upward and downward shortwave/longwave/near-infrared radiations (Fig. 3). Because the AWS is equipped with the ARGOS satellite transmitter, the in-situ measured data can be monitored near-real time. The present-day Greenland ice sheet has experienced drastic snow/ice mass losses due to various kind of processes, which affects the global climate system substantially through e.g. sea level rise. It is expected that the SIGMA-A AWS provides important basic measurement-based information of the rapidly changing physical conditions of the ice sheet.

On June 14, all members of ArCS II Cryosphere Program (Sub-1) observation team for FY2023 gathered for the in-situ field works. From right to left: Nozomu Okawara (MRI), Tetsuhide Yamasaki (Avangnaq Arctic Project), Masashi Niwano (MRI), Rigen Shimada (JAXA), Sojiro Sunako (NIED) and Motoshi Nishimura (NIPR).

The observation site in Qaanaaq Village is equipped with a kitchen and beds for each participant, providing a comfortable living environment. While living together at the site for more than one month, we will conduct field observations on the Greenland ice sheet and ice cap, set up and maintain observation equipment, and cooperate with each other.

Currently, we are steadily preparing for the installation of meteorological instruments (SIGMA-A) on the inland ice sheet, which is the most important mission of this year.

SIGMA-B site is one of the most important meteorological observation sites in the Arctic, where one of the Automatic Weather Station (AWS) is installed by the ArCS II project. This was the first visit to the site in about a year, and maintenance work was performed.
The team improved the performance of the instrument by quickly and accurately removing weather sensors that needed to be replaced and installing new ones. We also checked the overall functionality of the instrument, paying close attention to other functions such as battery charge status and communication capabilities.

After the maintenance work was completed, meteorological observations of the Qaanaaq Ice Cap resumed and monitoring will continue. These data will play an important role in the study of climate change and other environmental factors in the Arctic region. The data will also be shared with the international scientific community and is expected to contribute to the improvement of global climate models.

SIGMA-B AWS data is available on the Arctic Data archive System (ADS):

• SIGMA-B Automatic Weather Station (AWS) Data