1368 / 2024-09-25 18:45:52
Satellite-Based Evaluation of Submarine Permafrost Erosion at Shallow Offshore Areas in the Laptev and East Siberian Seas
Bottom sediments, coastal upwelling, seafloor erosion, submarine permafrost, thermal abrasion, suspended matter flux, wind and wave forcing, Laptev Sea, East Siberian Sea, Arctic Ocean.
Session 2 - Arctic Ocean: Physical Processes and their Effects on Climate and the Ecosystem
Abstract Accepted
Polina Adamovskaya / Shirshov Institute of Oceanology;Russian State Hydrometeorological University
Alexander Osadchiev / Russian Academy of Sciences;Shirshov Institute of Oceanology

The Arctic region is known to be particularly susceptible to the climate change compared to other regions of the Earth. Such indicators of the ongoing changes to the global climate system as reduction in sea ice extent and increase in air temperature that, according to some studies, has been happening in the Arctic at twice the global rate, play a crucial role in intensifying the process of permafrost degradation. Vast areas of seafloor in the Laptev and East Siberian seas consist of submarine permafrost, which has experienced intense degradation over the last decades and centuries. Thermal abrasion of the submarine permafrost results in upward advection of suspended matter, which could reach the surface layer in shallow areas. This process is visually manifested through increased turbidity of the sea surface layer, which is regularly detected in optical satellite imagery of the study areas. In this study, satellite data, wind and wave reanalysis, as well as in situ measurements are analysed in order to investigate the main mechanisms of seafloor erosion in shallow areas of the Laptev and East Siberian seas. Synoptic, seasonal and inter-annual variabilities in erosion of several shallow areas in response to wind and wave conditions are described and, using reanalysis data, daily suspended matter flux during ice-free periods from 1979 to 2021 is evaluated. The obtained results contribute to our understanding of subsea permafrost degradation, the sediment budget, and carbon and nutrient cycles in the Laptev and East Siberian seas.