ExtremeThaw Unprecedented permafrost thaw - Unlocking ground for new life and release of old soil carbon, pollutants and pathogens

Permafrost Permafrost thaw has severe consequences for ecosystems functions and services, ranging from the loss of slope stability, unlocking ancient carbon stored in the soils, releasing toxic compounds and microbes with melt water. At the same time, the unfreezing provides new ground for vegetation and soils. Environmental agencies are clearly aware of the potential ecological threats or 'benefits' related to permafrost thaw. Nevertheless, both policy makers and researchers have largely disregarded the ecological consequences of permafrost thaw as alpine areas are not intensively used. Our approach is to use the existing SLF permafrost and ground ice map as a basis to quantify (1) the risk of permafrost thaw in releasing ancient soil organic carbon to the atmosphere, legacy pollutants to alpine streams, and potentially pathogenic microorganisms to the environment and (2) the potential of newly unfrozen ground to harbour vegetation, microbial communities and to sequester C.