Changes in the Frequency of Extreme Cooling Events in Winter over China and Their Relationship with Arctic Oscillation

• Published in: Sustainability
• Main Authors: Shuaifeng Song, Xiaodong Yan
• Format: Article in Journal/Newspaper
• Language: English
• Published: MDPI AG 2021
• Subjects: extreme cooling events; Arctic Oscillation; winter in China; atmospheric circulation; envir; geo; Arctic; Human health
• Online Access: https://doi.org/10.3390/su132011491; https://doaj.org/article/bd6cc34a85b846d6b2df3e1e8d8915a7

Extreme weather and climate events are becoming increasingly frequent and have gained an increasing amount of attention. Extreme cooling (EC) events are a major challenge to socioeconomic sustainability and human health. Based on meteorological stations and NCEP/NCAR reanalysis data, this study analyzed the temporal and spatial distributions of EC events in winter in China by using the relative threshold and the relationship between EC events and the Arctic Oscillation (AO) index during the period of 1961–2017. The results show that the frequency of EC events in China decreased by 0.730 d in these 57 years, with a trend of −0.1 d/10 y. Northeast China had the highest frequency of EC events in winter, with an average of 4 d. In addition, EC events are significantly negatively correlated with the AO index in China, with a correlation coefficient of −0.5, and the AO index accounts for approximately 21% of the EC event variance. The strongest correlations are mainly located in Northwest China. Our research shows that significant changes in the mid–high latitude atmospheric circulation anomalies, which are associated with the AO, are responsible for EC events. These findings provide theoretical guidance for the prediction and simulation of EC events.