Permafrost Thaw Action Group The Permafrost Thaw Action Group was part of the Terrestrial Multidisciplinary distributed Observatories for the Study of Arctic Connections (T-MOSAiC). Together with MOSAiC [...] d collection of field data for quantifying permafrost thaw. It addresses the need for integrated observations of multiple connected components of permafrost landscapes, including soils, snow, and vegetation [...] vegetation. Illustration of the standarized permafrost monitoring protocol. The five spheres (snow, water, permafrost, vegetation and soil) with the associated parameters, measurement modes, and observation