Institute of Archaeology


PALAEOTHAW: Unlocking records of past permafrost thaw through isotopes of fossil bones

PALAEOTHAW is investigating past and present permafrost thaw through stable isotope analysis. 

Megaslump formed as a result of rapid permafrost thaw, Peel Plateau, NWT, Canada. Photograph by Julian Murton.

Permafrost (ground which remains frozen for a least two consecutive years) holds vast stores of carbon. When frozen, this carbon is isolated from the Earth’s atmosphere, but as our climate warms and permafrost thaws, it gets released as greenhouse gases, which further contribute to climatic warming. Permafrost thaw also destabilises landscapes, increasing the risk of erosion and landslides, which can damage homes, infrastructure, and transport networks.

To better predict and plan for changes to our permafrost landscapes in the future, processes of permafrost thaw need to be better understood. The past offers an important window through which we can do this. At the end of the last ice age, permafrost thawed across vast regions of Eurasia and North America. We have detected high magnitude changes in the sulphur isotope composition of the animals who lived in these environments at the time, which we suspect reflects changing permafrost conditions.

Bison horns preserved in permafrost sediments near Cherskii, Siberia. Photograph by Julian Murton.

To investigate the mechanisms that produced these sulphur isotope signals, we are analysing plant, soil, and water samples from modern permafrost environments. Applying this knowledge to fossil data, we will create high resolution records of past permafrost thaw and show how quickly permafrost responded to global and regional temperature change. This information will play an important part in informing us about the likely rate and nature of permafrost thaw in the future as our climate warms.

Related outputs


  • Leverhulme Trust RPG-2021-254 (2021-25)