[News Terms] The Cause of the Strongest Cold Wave: 'Arctic Amplification'

[Asia Economy Reporter Kim Jong-hwa] 'Arctic Amplification' refers to the phenomenon where the Arctic warms at more than twice the rate of the global average.

Antarctica is a continent covered by ice formed from snow that has accumulated over a long time without melting, whereas the Arctic consists of sea ice formed by frozen seawater. Because of this, unlike Antarctica, which has massive icebergs reaching thousands of meters, the sea ice in the Arctic is only about 1 to 5 meters thick.

Sea ice plays a very important role in the heat balance of the Arctic region. Since the sea ice covering most of the ocean reflects sunlight, a significant amount of heat does not accumulate on Earth but escapes. However, due to global warming, as the sea ice melts and the ocean surface area expands, the albedo decreases, causing the Earth to absorb more heat than before.

The Arctic sea ice is gradually melting away.
[Photo by Asia Economy DB]

In the Arctic, more solar heat is absorbed when the ocean is exposed compared to when it is covered by sea ice, and as more heat is absorbed, temperatures rise sharply. It is known that the Arctic temperature increase is generally about 2 to 2.5 times faster than the global average, but recent studies suggest it has accelerated up to 4 times faster.

As the Arctic temperature rises and the temperature difference between the Arctic and mid-latitudes decreases, the jet stream that surrounds the cold Arctic air weakens. When the temperature difference between the Arctic and mid-latitudes is large (i.e., when the Arctic temperature is lower), the jet stream strengthens, but when the jet stream weakens, the cold Arctic air moves down below the mid-latitudes, affecting the Korean Peninsula as well.