PERMAFROST AND THE CLIMATE FINGERPRINT IN SOILS

Soils in the zone of discontinuous permafrost reflect a temporal offset between the current state of the atmosphere and the climate conditions that initiatiated formation of ground ice. These thermal boundary conditions of sub-arctic pedogenesis are as usual mediated by water and sediment movement, tectonic context and lithology, and plant community succession over time. Consequently, the threshold for permafrost thaw is easy to quantify in terms of temperature, but challenging to predict within complex landscapes. We argue that sub-arctic soils illustrate the state of dynamic equilibrium in which most soils hover, between perfect translation of climate conditions into soil properties, and feedbacks that allow evidence of past climates to persist.