Shifts in Greenland interannual climate variability lead Dansgaard–Oeschger abrupt warming by hundreds of years

• DOI: 10.5194/cp-21-529-2025
• Publication Date: 2025-02-24T12:51:11Z
• Authors: Chloe A. Brashear; Tyler R. Jones; Valerie Morris; Bruce H. Vaughn; William H. G. Rob...; William B. Skorski; Abigail G. Hughes; Richard Nunn; Sune Olander Rasm...; Kurt M. Cuffey; Bo M. Vinther; Todd Sowers; Christo Buizert; Vasileios Gkinis; Christian Holme; Mari F. Jensen; Sofia E. Kjellman; Petra M. Langebroek; Florian Mekhaldi; Kevin S. Rozmiarek; Jonathan W. Rhein...; Margit H. Simon; Giulia Sinnl; Silje Smith-Johnsen; James W. C. White
• Keywords: Lead (geology); Abrupt climate change

Abstract. During the Last Glacial Period (LGP), Greenland experienced approximately 30 abrupt warming phases, known as Dansgaard–Oeschger (D–O) events, followed by cooling back to baseline glacial conditions. Studies of mean climate change across transitions reveal indistinguishable phase offsets between shifts in temperature, dust, sea salt, accumulation, and moisture source, thus preventing a comprehensive understanding “anatomy” D–O cycles (Capron et al., 2021). One aspect that has not been systematically assessed is how high-frequency interannual-scale climatic variability surrounding centennial-scale temperature changes transitions. Here, we utilize East Ice-core Project (EGRIP) high-resolution water isotope record, proxy for atmospheric circulation, quantify amplitude 7–15-year isotopic events 2–13, Younger Dryas, Bølling–Allerød. On average, cold stadial periods consistently exhibit greater than warm interstadial periods. Most notably, often find reductions band led warmings hundreds years. Such large offset two parameters ice core never documented cycles. However, similar centennial lead times have found proxies Norwegian Sea cover relative (Sadatzki 2020). Using HadCM3, fully coupled general circulation model, assess effects on at EGRIP. For range conditions, strong relationship line with our observations colder simulated enhanced EGRIP location. We also robust correlation year-to-year North Atlantic fluctuations strength Together, paleoclimate evidence model simulations suggest plays substantial role prior warming. This provides clue about anatomy should be target future studies.