Simulation of the AAO anomaly and its influence on the Northern Hemispheric circulation in boreal winter and spring
FAN Ke~ 1,2,3 ,WANG Hui-Jun~11 Nansen-Zhu International Research Center, Insititute of Atmospheric Physics, Chinese Academy of Sciences, Beijing 100029, China2 Department of Atmospheric Science, Yunnan University, Kunming 650091,China3 Graduate University of the Chinese Academy of Sciences, Beijing 100049,China
AAO anomaly and its influence on the Northern Hemispheric circulation and temperature over north of Asia are studied by analyzing the output of IAP9L-AGCM model. First, Sea temperature associated with Antarctic Oscillation (AAO) is investigated using IAP9L-AGCM model. The model simulation shows that the sea temperature at high latitude in SH may cause the AAO anomaly and the east tropical Pacific ocean is closely related to Pacific Southern America (PSA) teleconnection. Second, the results show that positive AAO tend to enhance Eurasian west wind and circulation anomaly at high latitude in NH, resulting in the increase of both surface temperature (SAT) and temperature at 850 hPa over North Asia during the boreal winter and spring. The meridional teleconnection responsible for possible mechanism is pronounced in the simulation. Therefore, model simulation supports our previous observations.