Global outlook from the Global Terrestrial Network for Permafrost (GTN-P): Changes in thermal state of permafrost and active layer thickness over the last decade

• Main Authors: Streletskiy, Dmitry, Biskaborn, Boris K., Romanovsky, Vladimir E., Smith, Sharon L.
• Format: Conference Object
• Language: unknown
• Published: 2016
• Subjects: Antarctic; Antarctic Peninsula; Arctic; Active layer thickness; Antarc*; Climate change; Global Terrestrial Network for Permafrost; GTN-P; International Polar Year; IPY; permafrost; Siberia
• Online Access: https://epic.awi.de/id/eprint/42848/; https://hdl.handle.net/10013/epic.49409

Long-term monitoring permafrost thermal state and active layer thickness (ALT) is critical in providing the baseline for assessment of climate change impacts in polar and high mountain regions, modeling of ecosystem processes and as an input for many engineering applications on permafrost among others. The Global Terrestrial Network for Permafrost (GTN-P) provides systematic long-term measurements of permafrost temperature and ALT, and is part of the Global Terrestrial Observing System (GTOS) of the Global Climate Observing System (GCOS). The GTN-P launched a sophisticated data management system (DMS), which allows automatic data submission, standardization, quality control, and processing. Presently 1250 permafrost boreholes and 250 active layers sites are registered within the DMS (gtnpdatabase.org), but the geographic distribution of sites and length of observations vary considerably among regions. Using DMS capabilities we selected sites with data available during the last International Polar Year (IPY) and in the recent 4 years and estimated changes in thermal state of permafrost and active layer thickness between the two reference periods. The results show that following air temperature trends, permafrost temperature has generally increased across permafrost domain, however, there is considerable spatial variability. The highest increases in permafrost temperature are found in Canadian High Arctic and are pronounced in regions with cold continuous permafrost such as Siberia and North America. In the sub-arctic, where permafrost temperatures are relatively high, the warming trend is less pronounced and permafrost temperature is similar to that of the IPY snapshot. In alpine permafrost areas, however, most measurement sites also show significant warming since 2009. ALT exhibits large interannual variability, but has generally increased in the majority of regions, especially in European Arctic sector where several sites experienced permafrost degradation. In several sites at northwest Antarctic Peninsula, ALT ...