Unraveling the secrets of the Arctic: how melting ice is affecting our climate

 Recent decades have witnessed rapid changes in the Arctic climate, with rates of warming exceeding the global average by three to four times. This surprising climatic phenomenon of "Warm Arctic, Cold Eurasia" has profound consequences, arousing scientific interest in the mechanisms underlying it.

Arctic sea ice extent has been declining rapidly, decreasing by about 12.2% per decade in summer over the past 40 years. Previous studies have shown that the decline of Arctic sea ice plays a key role in creating a "Warm Arctic, Cold Eurasia" climate regime. However, the limitations of available observations have raised questions about whether internal atmospheric variability may be masking the true impact of sea ice decline.

Dr. Shenping He, a senior scientist at the Geophysical Institute at the University of Bergen and corresponding author of the study published in Advances in Atmospheric Sciences, used large-scale experiments to unravel the effects of Arctic sea ice loss and internal atmospheric variability on this climate regime.

In cooperation with various international institutions, the study showed that the reduction of sea ice could indeed trigger a "Warm Arctic, Cold East Asia" model. However, the cooling effect of East Asia due to reduced sea ice can easily be obscured by atmospheric variability, leading to larger cold or warm anomalies.

In another study published in the same journal, the team also investigated future changes in Arctic sea ice, focusing on newly formed winter ice. As the Arctic warms, the increase in the area of the open ocean in winter contributes to the formation of new ice. This recent ice provides important information about Arctic-air-sea interactions and broader atmospheric coupling in the Northern Hemisphere.

Their findings indicate that newly formed ice in the Arctic is expected to continue to increase until mid-century under different emission scenarios, stabilizing thereafter under more moderate scenarios, but decreasing under higher emissions.

These new studies not only quantified the direct impact of Arctic sea ice on winter temperatures, but also found a trend toward increased ice formation in the winter Arctic. The obtained data provide an important insight into climate change in the era of the "new Arctic".