Over the past 10 years, due to the Arctic Amplification of global warming in the North Pole region, there have been situations of accelerated temperature rise and drastic decrease in sea ice area in the North Pole;nevertheless, the air temperature of continents in the north hemisphere continue to drop.Particularly in recent years, there have been abnormally cold winters in large areas.During the winter season in China, the cold air activity that causes temperature drop, including cold waves that can cause dramatic temperature drops throughout the entire country, often travels southward together with the cold high pressure on the ground.Therefore, winter temperature anomaly in China could be related to the anticyclone activities on the Eurasian continent.In this study, on the basis of Lagrange’s theories, the NCEP/NCAR reanalysis data are used to trace anticyclone activities on the Eurasian continent from 1979—2012, and the strength index of the winter anticyclone on the Eurasian continent is defined.Based on this, we then analyze the features of anticyclone on the Eurasian continent for the past 30 years, as well as its relationship to winter temperature in China.The results show the following:
1)The index of anticyclone intensity exhibits obvious inter-annual and inter-decades fluctuations in the winter during 1979—2012, and the ACI exhibits a pronounced intensification over the past 10 years.
2)The winter temperature anomaly in China is negatively correlated to the strength of anticyclone activities on the Eurasian continent, i.e.when the anticyclone activities are strong, most part of China are colder, and vice visa.The negative anomalies of winter temperature increases in China in the past years were mostly related to the strong phase of anticyclone activities on the Eurasian continent.
3)Anticyclones with short lifetime occur most frequently, and have a more apparent impact on the winter temperature in China in larger regions.Anticyclones with long lifetimes occur less frequently, and mainly affect the temperatures of the Liaoning and central Inner Mongolia regions.Anticyclones with extremely long lifetimes account for 10%.
4)The Mongolian plateaus are the key region for winter anticyclone activities on the Eurasian continent, with 40% of anticyclones passing this region annually.They are highly mobile, with the Scandinavia peninsula, Mediterranean, Caspian Sea, Black Sea, Aral Sea and central Siberia areas as their main origins.