Synchronous timing of abrupt climate changes during the last glacial period

• Published in: Science (American Association for the Advancement of Science) 2020-08, Vol.369 (6506), p.963-969
• Main Authors: Corrick, Ellen C., Drysdale, Russell N., Hellstrom, John C., Capron, Emilie, Rasmussen, Sune Olander, Zhang, Xu, Fleitmann, Dominik, Couchoud, Isabelle, Wolff, Eric
• Format: Article
• Language: English
• Subjects: Climate; Climate change; Climatology; Computer simulation; Continental interfaces, environment; Earth Sciences; Environmental Sciences; Geochemistry; Glacial periods; Global Changes; Monsoons; Ocean, Atmosphere; Sciences of the Universe; Temperature
• ISSN: 0036-8075; 1095-9203
• DOI: 10.1126/science.aay5538

Many geographically dispersed records from across the globe reveal the occurrence of abrupt climate changes, called interstadial events, during the last glacial period. These events appear to have happened at the same time, but the difficulty of determining absolute dates in many of the records have made that proposition difficult to prove. Corrick et al. present results from 63 precisely dated speleothems that confirm the synchrony of those interstadial events. Their results also provide a tool with which to validate model simulations of abrupt climate change and calibrate other time series such as ice-core chronologies. Science , this issue p. 963 Rapid climate changes occurred synchronously throughout middle and high latitudes during the last glacial period. Abrupt climate changes during the last glacial period have been detected in a global array of palaeoclimate records, but our understanding of their absolute timing and regional synchrony is incomplete. Our compilation of 63 published, independently dated speleothem records shows that abrupt warmings in Greenland were associated with synchronous climate changes across the Asian Monsoon, South American Monsoon, and European-Mediterranean regions that occurred within decades. Together with the demonstration of bipolar synchrony in atmospheric response, this provides independent evidence of synchronous high-latitude–to-tropical coupling of climate changes during these abrupt warmings. Our results provide a globally coherent framework with which to validate model simulations of abrupt climate change and to constrain ice-core chronologies.