Observed contribution of Barents-Kara sea ice loss to warm Arctic-cold Eurasia anomalies by submonthly processes in winter

Abstract

The warm Arctic-cold Eurasia (WACE) pattern of surface air temperature anomalies is a prominent feature of the Eurasian climate variations during boreal winter. The interannual WACE anomalies are accompanied by sea ice loss in the Barents-Kara (BK) seas, however, the causality between them remains controversial because of large internal atmospheric variability over subarctic Eurasia in winter. Here we disentangle the contribution of BK sea ice loss to the WACE anomalies based on a statistical decomposition approach. An anticyclonic circulation anomaly over subarctic Eurasia that forces the WACE anomalies is found to reach its peak 3 days prior to BK sea ice loss. After excluding this prior atmospheric forcing signature, the East Asian cooling matures about 15 days later as a result of the weakened moisture transport associated with the enhanced BK downstream ridge and East Asian trough due to BK sea ice loss. The results suggest that BK sea ice loss contributes ~65% and ~81% of the WACE-related East Asian cooling and Arctic warming at interannual timescale, respectively, whereas the WACE-related cooling over central Eurasia primarily results from internal atmospheric variability. Such submonthly lagged East Asia cooling caused by BK sea ice loss could be helpful in predicting winter extreme cold events over East Asia.

Unprecedented July Rainfall in North China in 2021: Combined Effect of Atlantic Warming and Arctic Sea‐Ice Loss

“…Figure 4 shows that the SIC over LESS (LESIC) was not only significantly correlated with NCPI, but was also at a record low in 2021. The LESIC could have decreased the sea surface albedo and enhanced the absorption of solar shortwave radiation, thereby causing a positive SSTA and inducing an anticyclonic anomaly at the lower level (Honda et al., 1999; Yan et al., 2021; Li, Zhang, et al., 2023). As a result, the polar vortex split and shifted southwards, which centered over the Novaya Zemlya, Bering Strait, and Queen Elizabeth Islands (Figure 3f).…”

The Impacts of Regime Shift in Summer Arctic Oscillation on Precipitation in East Asia

“…Although the AO is primarily generated by internal atmospheric dynamics [90], it may also be influenced by the lower-level sea surface temperature [12,91,92]. Some studies document that the reduction of Arctic sea ice can have distant impacts on the Eurasian climate by stimulating the propagation of Rossby waves [93][94][95]. Furthermore, global warming has led to frequent extreme precipitation events worldwide [96,97], and interdecadal changes in AO also occur under the background of global warming [98].…”

The linkage between autumn Barents-Kara sea ice and European cold winter extremes

“…Moreover, it has been linked to the occurrence of cold and harsh winters over Europe. Overall, the reduction of sea ice cover in the Barents Sea has emerged as a critical environmental and climatic issue in recent years, with far-reaching consequences for weather patterns and temperatures across Europe, particularly during winter (Honda et al, 2009;Petoukhov and Semenov, 2010;Li et al, 2023). This reduction of sea ice during autumn and early winter underscores the Arctic ecosystem's vulnerability and provides insights into the peculiar meteorological events occurring further south-the colder and more severe winters experienced across Europe.…”