Observed bottom warming in the East Siberian  Sea driven by the intensified vertical mixing

Wang, Xiaoyu; Mu, Longjiang; Chen, Xianyao

doi:https://doi.org/10.5194/os-21-577-2025

Articles | Volume 21, issue 2

https://doi.org/10.5194/os-21-577-2025

© Author(s) 2025. This work is distributed under
the Creative Commons Attribution 4.0 License.

https://doi.org/10.5194/os-21-577-2025

© Author(s) 2025. This work is distributed under
the Creative Commons Attribution 4.0 License.

Articles | Volume 21, issue 2

Research article

|

13 Mar 2025

Research article |

| 13 Mar 2025

Observed bottom warming in the East Siberian Sea driven by the intensified vertical mixing

Xiaoyu Wang, Longjiang Mu, and Xianyao Chen

Data sets

Oceanographic data collected within the Pacific Arctic Ocean by the Russia and China cruises in the summer of 2016 [Data set] Xiaoyu Wang and Yan He https://doi.org/10.5281/zenodo.4507584

ERA5 hourly data on single levels from 1940 to present H. Hersbach et al. https://doi.org/10.24381/cds.adbb2d47

Global Ocean Physics Reanalysis Copernicus Marine Service https://doi.org/10.48670/moi-00021

Global Ocean Gridded L 4 Sea Surface Heights And Derived Variables Reprocessed 1993 Ongoing Copernicus Marine Service https://doi.org/10.48670/moi-00148

Short summary

The East Siberian Sea has nearly 80 % of the subsea permafrost worldwide. The cold layer with a temperature around −1.5 ºC above the seafloor prevents heat transporting from above to melt permafrost and release methane from sediments. However, we observed a warming trend at the seafloor caused by wave-induced vertical mixing in the shelf. The intensified mixing can transport enormous heat downward, leading to warming of more than 3 °C at the bottom, putting the subsea permafrost at high risk.