Interdecadal variation in the relationship between November Barents Sea Ice and the subsequent March Eurasian surface air temperature

Changes in Arctic sea ice concentration (SIC) significantly affect mid- to low-latitude climates, yet research regarding its effect on Eurasian climate change in early spring remains insufficient. Based on reanalysis datasets and model simulations, this study reveals a significant weakening in the relationship between the dipole pattern with opposite SIC anomalies in the northern (76^◦–82^◦N, 20^◦–50^◦E) and southern (70^◦–76^◦N, 47^◦–67^◦E) regions over the Barents Sea during late autumn and the dipole mode of surface air temperature (SAT) with opposite anomalies in the southern (15^◦–45^◦N, 35^◦–100^◦E) and northern (50^◦–75^◦N, 15^◦–180^◦E) regions over Eurasia during early spring around the 2000s. This change is attributed to different spatial patterns of SIC interannual anomalies in two subperiods. During Period 1 (1978/1979–1999/2000), the dipole SIC anomalous pattern may persist from November toward the following March, which modulates the SAT in situ by affecting turbulent heat flux and longwave radiation, which further strengthening eastward-propagating wave trains originating from the North Atlantic and inducing the dipole SAT pattern in Eurasia in the following March. In contrast, during Period 2 (2000/2001–2021/2022), consistent interannual SIC anomalies over the Barents Sea in late autumn weakened this relationship due to less pronounced wave trains propagating from the Barents Sea to Eurasia. The findings of this paper reveal that different patterns of Arctic SIC can lead to varying characteristics in the Eurasian climate, suggesting the complex relationship between Arctic and Eurasian climates.