Abstract:During June-August 2010, significant circumglobal teleconnections existed in the Northern Hemisphere which originated from the negative disturbance around the exit of upper level jet stream over the Atlantic. The disturbance propagated downstream along the teleconnection wave train, causing Russian heat wave, heavy rains and floods in Pakistan and northwestern and northeastern China. The teleconnection analysis shows that the negative disturbance firstly caused positive perturbation and the development of blocking high in western Russia, resulting in persisting high temperature and drought. Secondly, the negative disturbance propagated to northern West Asia, causing cold air to move southward and meet the northward and westward Indian summer monsoons in northern Pakistan and produced torrential rains. In early August, the disturbance continued to propagate downstream along the upper level jet stream over Asia, causing floods in northwestern and northeastern China and the Korea Peninsula. The sudden rain storm and landslide in Zhouqu, Gansu Province and the extremely heavy rain in Songhuajiang River region occurred just in this stage. The meridional circulation over the Eurasia developed exceptionally during 2010 summer and the meridional cell of the upper level jet stream was great, causing cold air from high latitudes and warm air from low latitudes to interact continuously. This induced the establishing, strengthening, and maintaining of high latitude blocking high in western Russian, and low latitude severe floods in Pakistan and rainstorm in mid latitudes of China. Monsoons acted as a key factor for the heavy rains and floods with the display of interaction of two warm and humid air flows from the Arabian Sea and Bay of Bengal and the southward cold air flow along the blocking high over northern Pakistan, as well as the interaction of warm and humid air flows from the Indian Ocean and the Pacific and the moisture from westerlies over northeastern China and the Korea Peninsula.