Amderma open water period characteristics based on satellite observation of the sea ice concentration, archives for the 1979-2018 period

Abstract

The aim of this study is to estimate the Amderma station (the Kara Sea) ice-free period using sea ice concentration satellite datasets in comparison to observation data. The work follows the research performed for the Western Coast of the Yamal (Marresalya) being the part of the Arctic coastal dynamics study. The OSISAF, JAXA and NSIDC (resolution 25 km, 1 day, 1979-2018) sea ice concentration datasets were used to characterize the water area adjacent to the station within the 30-50 km radius. The threshold (15%-concentration) and the author's "sliding window" methods were used to detect open water start and end dates. According to the satellite data, the ice-free period in the 30-50-kilometer water area along the Amderma coast is shifted by 2-3 weeks closer to December if compared to observations. At Amderma station (in the contrast to Marresalya), there are no significant trends in ice-free period start dates. On the adjacent water area, the destruction of the ice cover occurs earlier by 3-6 weeks if compared to the 1980’s, and the end date by 3-6 weeks later. The duration of the open water period over 40 years has increased by 32-36 days at the station and by 52-120 days (40-100%) in the adjacent water area.