Researchers link the warming of the Arctic to severe winter weather in mid-latitudes and extrapolate its future

Images of melting glaciers and polar bears stranded on shrinking sea ice in the Arctic are perhaps the most striking images that have been used to highlight the effects of global warming. However, they do not convey the full extent of the consequences of Arctic warming. In recent years, there has been growing recognition of the Arctic’s role in driving extreme weather events in other parts of the world.

While the Arctic is warming twice as fast as the global average, mid-latitude winters have seen colder and more severe weather events. For example, the 2022-2023 winter saw record cold temperatures and snowfall in Japan, China and Korea. Likewise, many parts of Eurasia and North America experienced severe cold snaps, with heavy snowfalls and prolonged periods of sub-zero temperatures.

While there are multiple theories for this climate phenomenon, an international team of researchers led by Professor Jin Ho-yeon of the Gwangju Institute of Science and Technology (GIST), Korea set out to study the relationship between the northern hemisphere’s harsh winters and the Earth. Melting Arctic sea ice, a phenomenon referred to as “Warm-Cold Arctic” (WACC), and how this relationship has changed as the climate warms.

In their study published in npj climate and atmospheric sciencesthe researchers looked at historical climate data and turned to climate projection models to explore a possible relationship and assess how this phenomenon might be affected by different global warming scenarios.

Drawing on climate data from the European Center for Medium-Range Weather Forecasting (ECMWF) going back nearly 40 years, the researchers correlated winter temperatures in eastern Asia and North America with those of the Barents-Kara Sea and eastern Siberia-Chukchi. sea ​​in the Arctic region.

They note that lower winter temperatures in East Asia and North America are usually accompanied by higher temperatures in the Arctic sea. However, they also found that in some winters, such as the 2017/18 winter in East Asia, this pattern did not hold, suggesting that this association includes potential uncertainty due to factors other than Arctic sea temperatures that were at play.

However, using climate projections from the Additional Warming Predictor and Impact Experiments (HAPPI) that were intended to project future climate under 1.5°C to 2°C warming scenarios, the researchers found that the WACC pattern persists even when global temperatures have rose.

However, they found that the relationship between Arctic sea temperature and East Asian temperatures became more ambiguous as global warming intensified.

“We found that the relationship between Arctic warming and mid-latitude cold weather events will become more ambiguous under warmer climates, challenging projections of future winter temperatures,” says Yong-Hung, Ph.D. GIST student and member of the research team.

“Our study shows that while one can expect cold waves from mid-latitude Arctic warming to persist into a warmer future, they will become more difficult to predict,” adds Professor Jin Ho Yoon.

The results of this study highlight the importance of ongoing efforts to better understand the interactions between warming in the Arctic and mid-latitude climate as a means of creating alternative predictors of upcoming winter weather extremes.