Data for "Extremely wet summer events enhance permafrost thaw for multiple years in Siberian tundra"

Permafrost thaw can accelerate climate warming by releasing carbon from previously frozen soil in the form of greenhouse gases. Rainfall extremes have been proposed to increase permafrost thaw, but the magnitude and duration of this effect are poorly understood. Here we present empirical evidence sh...

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Bibliographic Details
Main Authors: Magnússon, R. Í. (Wageningen University & Research) ORCID=0000-0003-2254-2612, Hamm, A. (Stockholm University)
Other Authors: Magnússon, R. Í. (Wageningen University & Research), RightsHolder, Hamm, A. (Stockholm University), RightsHolder
Format: Dataset
Language:English
Published: 2022
Subjects:
Ice
Online Access:http://nbn-resolving.org/urn:nbn:nl:ui:13-e1-t4yg
https://easy.dans.knaw.nl/ui/datasets/id/easy-dataset:234258
Description
Summary:Permafrost thaw can accelerate climate warming by releasing carbon from previously frozen soil in the form of greenhouse gases. Rainfall extremes have been proposed to increase permafrost thaw, but the magnitude and duration of this effect are poorly understood. Here we present empirical evidence showing that one extremely wet summer (+100mm; 120% increase relative to average June – August rainfall) enhanced thaw depth by up to 35% in a controlled irrigation experiment in an ice-rich Siberian tundra site. The effect persisted over two subsequent summers, demonstrating a carry-over effect of extremely wet summers. Using soil thermal hydrological modelling, we show that rainfall extremes delayed autumn freeze-up and rainfall-induced increases in thaw were most pronounced for warm summers with mid-summer precipitation rainfall extremes. Our results suggest that, with rainfall and temperature both increasing in the Arctic, permafrost will likely degrade and disappear faster than is currently anticipated based on rising air temperatures alone.