Summary/Abstract
High-latitude peatlands, which store one third of the global soil carbon, are changing rapidly in response to climate change, including permafrost thaw. This article reconstructs hydrological conditions since the seventeenth century using testate amoeba data from 103 high-latitude peat archives. This research shows that 54% of the peatlands have been drying and 32% have been wetting over this period, illustrating the complex ecohydrological dynamics of high latitude peatlands and their highly uncertain responses to a warming climate.