Temporal trend and dynamics of the active layer at different monitoring points in Maritime Antarctica and Peninsula

Antarctica provides a unique opportunity to understand changes in permafrost and global climate. Four monitoring sites were selected between maritime Antarctica and the Peninsula to study the temporal trend, air and soil temperature, and dynamics of the active soil layer. The Mann-Kendall method was used to determine the presence of a trend (complete series, seasonal and annual), the Sen-Slope test to check the degree of slope of the trend, and the Pettitt test to determine the exact date of the sudden change in the trend line. The thickness of the active layer - ALT - was estimated using the monthly maximum temperature. The local effects of each site influenced the dynamics of the active layer and the thermal regime. Deception heat balance was influenced primarily by geothermal activity, mainly at depth. In summer and autumn, the isotherm increases with depth at Low Head, Deception and Hope Bay. The Mann-Kendall test was significant for all sites studied. The ALT was thicker near the peninsula than in places in Shetland. Global warming causes increasingly frequent and intense extreme events, added to natural variability and the effect of local and regional climate factors.