Simulation of the AAO Anomaly and its Influence on the Northern Hemispheric Circulation in Boreal Winter and Spring

Abstract

AbstractThe 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 the IAP9L‐AGCM model. The model simulation shows the sea temperature at high latitudes 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 tends to enhance Eurasian west wind and circulation anomaly at high latitudes in NH resulting in the increase of both surface temperature (SAT) and temperature at 850hPa 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.