A study on the relationship between the Arctic and mid-latitude temperature in winter

Abstract

Arctic amplification and sea ice loss has gotten stronger as global mean surface temperature rises. Moreover, warmer Arctic could influence mid-latitude climate, particularly during boreal winter season.30 For example, temperature over East Asia (North America) is linked to that over the Barents-Kara sea (the East Siberian-Chukchi sea)18 in such a way that warmer Arctic and colder mid-latitude, which is known as the Warm Arctic Cold Continent (WACC).44 Here we identify the linkage between Arctic warming and mid-latitude cooling by introducing conditional probability. During individual winter from 1979 to 2018, negative correlation between Arctic and midlatitude temperature is found in general. In details, East Asian cooling is related to Barents-Kara sea and Greenland warming, North American cooling is related to North Pacific warming. However, there are some years with stronger connection but others with very weak. Conditional sampling based on rapid tropospheric daily warming (RTDW) occurred in the Arctic, high frequencies of cold in mid-latitude regions are observed. Although it is not demonstrated that warming in the Arctic is not the direct cause of the cold in the mid-latitude region, our finding suggests that Arctic warming and cold mid-latitude is well connected and cannot be independent of each other.