Cajada et al. (2026): Reversal of the warm Arctic -cold Eurasia intraseasonal coupling by CO₂ removal
M. Inês Cajada, Seok-Woo Son, Ye-Jun Jun, Shih-Yu Simon Wang, Jin-Ho Yoon and Seung-Ki Min, IN: Environmental Research Letters, https://doi.org/10.1088/1748-9326/ae6dd7
Midlatitude winter climate variability arises partly from its interactions with Arctic climate variability. A prominent example is the intraseasonal coupling between warm temperature anomalies over the Barents–Kara Seas and cold anomalies over central Eurasia, commonly referred to as the Warm Arctic–Cold Eurasia (WACE) relationship. Numerous studies have examined how this coupling may weaken under continued greenhouse gas warming. Yet, it remains unclear whether the WACE response to CO₂ warming reflects an irreversible change in atmospheric circulation or a reversible response to altered background conditions. In this study, the reversibility of the WACE relationship is investigated using a large-ensemble CO₂ ramp-up and ramp-down experiment. The WACE relationship is projected to weaken under increasing CO₂ concentrations.