Abstract:
Based on the definition of Kosaka's Silk Road teleconnection, this paper calculates the index of the autumn Eurasian wave trains and studies the relationship between the autumn Eurasian wave train and East Asian atmospheric circulation, precipitation and temperature in autumn in China. The results show that the autumn Eurasian wave train is positively correlated with the autumn precipitation in Northeast China, and negatively correlated with the autumn rain in West China. The results also show that there is a " −+−” anomalous wave from west to east over the Eurasia continent of 40°—60°N in the geopotential height field when the autumn Eurasian wave train is in the positive phase in autumn. The wave train leads to an abnormally low−pressure cyclonic circulation in Northeast China, resulting in an abnormally great amount of precipitation in the region. In comparison, it rains little in West China in autumn, due to the significant downdraft flow, weak anti−cyclonic circulation and weak water supply. On the other hand, the index of the autumn Eurasian wave trains in Northwest China is negatively correlated with the surface temperature of Northwest China, North Sichuan and part of Guizhou Province, probably because the abnormally great northwesterly airflow leads the cold air southward.