Permafrost thermal snapshot and active-layer thickness in Svalbard 2016-2017

This is chapter 1 of the State of Environmental Science in Svalbard (SESS) report 2018 (https://sios-svalbard.org/SESS_Issue1).

Permafrost plays an important role in the Earth System underlying 25% of the terrestrial parts of Planet Earth. It is a thermal condition occurring in the ground in cold regions, and is defined as ground (soil, sediment, or rock) that remains at or below 0°C for two or more consecutive years.

We have for the first time gathered information from all existing permafrost observation infrastructure in Svalbard. We report on the two essential climate variables (ECVs) for permafrost, the permafrost thermal state and the active layer thickness based on the existing permafrost monitoring sites in Svalbard. Several new boreholes were established in different parts of western Svalbard during the last years, thanks to efforts from Italy, Russia, Germany, Poland and Norway. These boreholes have allowed us to compare the permafrost ECVs from sites in Ny-Ålesund, Kapp Linne, Barentsburg, Adventdalen and Hornsund through the hydrological year 2016-2017. We have studied ground temperatures and interpolated active-layer thickness in 11 boreholes, and two active-layer monitoring grids. Svalbard has the warmest permafrost this far north.