Volcanic influence on centennial to millennial Holocene Greenland temperature change

• Published in: Scientific Reports
• Main Authors: Takuro Kobashi, Laurie Menviel, Aurich Jeltsch-Thömmes, Bo M. Vinther, Jason E. Box, Raimund Muscheler, Toshiyuki Nakaegawa, Patrik L. Pfister, Michael Döring, Markus Leuenberger, Heinz Wanner, Atsumu Ohmura
• Format: Article in Journal/Newspaper
• Language: English
• Published: Nature Portfolio 2017
• Subjects: Medicine; R; Science; Q; Greenland; Greenland ice core; ice core; North Atlantic; Sea ice
• Online Access: https://doi.org/10.1038/s41598-017-01451-7; https://doaj.org/article/52cbc67321eb436fb717441092e04d36

Abstract Solar variability has been hypothesized to be a major driver of North Atlantic millennial-scale climate variations through the Holocene along with orbitally induced insolation change. However, another important climate driver, volcanic forcing has generally been underestimated prior to the past 2,500 years partly owing to the lack of proper proxy temperature records. Here, we reconstruct seasonally unbiased and physically constrained Greenland Summit temperatures over the Holocene using argon and nitrogen isotopes within trapped air in a Greenland ice core (GISP2). We show that a series of volcanic eruptions through the Holocene played an important role in driving centennial to millennial-scale temperature changes in Greenland. The reconstructed Greenland temperature exhibits significant millennial correlations with K+ and Na+ ions in the GISP2 ice core (proxies for atmospheric circulation patterns), and δ18O of Oman and Chinese Dongge cave stalagmites (proxies for monsoon activity), indicating that the reconstructed temperature contains hemispheric signals. Climate model simulations forced with the volcanic forcing further suggest that a series of large volcanic eruptions induced hemispheric-wide centennial to millennial-scale variability through ocean/sea-ice feedbacks. Therefore, we conclude that volcanic activity played a critical role in driving centennial to millennial-scale Holocene temperature variability in Greenland and likely beyond.