Marine Heatwaves in Siberian Arctic Seas and Adjacent Region

Abstract

We used a satellite-derived global daily sea surface temperature (SST) dataset with resolution 0.25 × 0.25∘ to analyze interannual changes in the Arctic Shelf seas from 2000 to 2020 and to reveal extreme events in SST distribution. Results show that the second decade of the 21st century for the Siberian Arctic seas turned significantly warmer than the first decade, and the increase in SST in the Arctic seas could be considered in terms of marine heatwaves. Analyzing the spatial distribution of heatwaves and their characteristics, we showed that from 2018 to 2020, the surface warming extended to the northern deep-water region of the Laptev Sea 75∘ to 81∘N. To reveal the most important forcing for the northward extension of the marine heatwaves, we used three-dimensional numerical modeling of the Arctic Ocean based on a sea-ice and ocean model forced by the NCEP/NCAR Reanalysis. The simulation of the Arctic Ocean variability from 2000 to 2020 showed marine heatwaves and their increasing intensity in the northern region of the Kara and Laptev seas, closely connected to the disappearance of ice cover. A series of numerical experiments on the sensitivity of the model showed that the main factors affecting the Arctic sea-ice loss and the formation of anomalous temperature north of the Siberian Arctic seas are equally the thermal and dynamic effects of the atmosphere. Numerical modeling allows us to examine the impact of other physical mechanisms as well. Among them were the state of the ocean and winter sea ice, the formation of fast ice polynias and riverine heat influx.

Model Study of the Effects of Climate Change on the Methane Emissions on the Arctic Shelves

“…We have found that sea ice and atmospheric dynamics primarily determine the variability of the Siberian shelf water state. We refer to [11] to show that early ice release and increased air temperature contributed to the formation of an anomalously high surface water temperature for this region, making it possible to consider these events as marine heatwaves [71]. For the present study, the most important is that the model shows the significant reduction in the sea ice cover in summer and sea surface temperature rise at the Siberian shelves during the last years of the second decade of the 2000s.…”

“…As a member of the international project FAMOS (Forum for Arctic Modeling & Observational Synthesis, [67]), the model was tested in coordinated modeling studies and compared with observational data [68][69][70]. Recent studies on the SibCIOM simulation [11,45] are closely connected with the present investigation. We have found that sea ice and atmospheric dynamics primarily determine the variability of the Siberian shelf water state.…”

“…The numerical model SibCIOM was used previously in numerous studies of interannual and seasonal variability of the water and sea ice of the Arctic Ocean and the Arctic Shelves [11,[43][44][45]64]. The simulation results show the main processes related to climatic changes known from the analysis of observations.…”

“…Additional absorption of heat by the sea surface is followed by the warming of Arctic seawater [7][8][9]. An assessment based on a satellite-derived global daily sea surface temperature data set [10] has shown that the second decade of the 21st century for the Siberian Arctic seas was significantly warmer than the first decade [11]. The authors demonstrated that at the end of the second decade, the Siberian Arctic seas experienced anomalous warming.…”

Numerical modeling of methane hydrates dissociation in the submarine permafrost

“…Permafrost is widespread in the Arctic region, both in the continental region and in the vast areas of the shallow shelf of the Arctic seas [1][2][3]. A large amount of methane can be found in permafrost in a hydrated form [4].…”