Recent summer warming in northwestern Canada exceeds the Holocene thermal maximum

Eastern Beringia is one of the few Western Arctic regions where full Holocene climate reconstructions are possible. However, most full Holocene reconstructions in Eastern Beringia are based either on pollen or midges, which show conflicting early Holocene summer temperature histories. This discrepan...

Full description

Bibliographic Details
Published in:Nature Communications
Main Authors: Porter, Trevor J., Schoenemann, Spruce W., Davies, Lauren J., Steig, Eric J., Bandara, Sasiri, Froese, Duane G.
Format: Text
Language:English
Published: Nature Publishing Group UK 2019
Subjects:
Article
Arctic
Canada
Yukon
Climate change
permafrost
Beringia
Online Access:http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6456611/
http://www.ncbi.nlm.nih.gov/pubmed/30967540
https://doi.org/10.1038/s41467-019-09622-y
Description
Summary:Eastern Beringia is one of the few Western Arctic regions where full Holocene climate reconstructions are possible. However, most full Holocene reconstructions in Eastern Beringia are based either on pollen or midges, which show conflicting early Holocene summer temperature histories. This discrepancy precludes understanding the factors that drove past (and potentially future) climate change and calls for independent proxies to advance the debate. We present a ~13.6 ka summer temperature reconstruction in central Yukon, part of Eastern Beringia, using precipitation isotopes in syngenetic permafrost. The reconstruction shows that early Holocene summers were consistently warmer than the Holocene mean, as supported by midges, and a thermal maximum at ~7.6–6.6 ka BP. This maximum was followed by a ~6 ka cooling, and later abruptly reversed by industrial-era warming leading to a modern climate that is unprecedented in the Holocene context and exceeds the Holocene thermal maximum by +1.7 ± 0.7 °C.

Similar Items