Extension of the Ice-Free Period in the Laptev Sea According to Remote Sensing Data

Abstract

The features of the spatial distribution of the long-term average ice-free period (IFP) characteristics and their trends in the Laptev Sea are calculated and described quantitatively based on the microwave remote sensing data for 1979–2021. The spatial distribution of the long-term average duration of the IFP mainly follows the spatial distribution of the long-term average IFP start dates. The highest value of the long-term average duration of the IFP is observed in the areas where the Anabar–Lena and Western New Siberian stationary flaw polynyas are formed. It is shown that south of 78° N, the duration of the IFP increased statistically significantly by +17 ± 7 days/10 year on average. The areas of the Laptev Sea north of 80° N are characterized by statistically insignificant changes in IFP characteristics. The duration of the IFP extends due to both the shift of the IFP start dates to the earlier time (an average rate of changes is –10 ± 4 days/10 year) and the shift of the IFP end dates to a later time (an average rate of changes is +8 ± 4 days/10 year).