Abstract:

In this paper, the spreading way in the southern hemisphere that anomalous warm water piled in tropical eastern Pacific is analysed and then impact of ENSO episodes on the variability of the Antarctic sea ice extent is investigated by using a dataset from 1970 to 2002. The analysis results show that in ENSO period the anomalous warm water piled in tropical eastern Pacific is poleward propagation and westward propagation along southern equator current hasn't been discovered . The time of the anomalous warm water poleward propagation is about 1 year or so. ENSO episodes has a close relationship with the sea ice extent in the Amundsen Sea, Bellingshausen Sea and Antarctic Peninsula. Two years after El Nino appears, the sea ice in the Amundsen Sea, Bellingshausen Sea, especially in the Antarctic Peninsula decreases obviously. The process that El Nino influences Antarctic sea ice extent is that the warm water piled in tropical eastern Pacific is propagated poleward along the coast of southern America and causes the anomalous temperature raise near the pole and then lead to the decrease of the sea ice in Amundsen Sea, Bellingshausen Sea and Antarctic Peninsula. The sea ice has decreased obviously since 1980s, which has relevance to the frequent appearance of El Nino.