不同类型ENSO事件对初冬北极海冰的影响

Impacts of different ENSO events on the early-winter Arctic sea ice

基于1951—2019年NCEP/NCAR再分析资料、Hadley环流中心海温、海冰密集度资料,通过合成分析和诊断温度异常方程,研究不同类型ENSO对初冬北极海冰的影响。结果表明,EP La Niña发展年初冬(11—12月),巴伦支—喀拉海海冰异常减少;CP La Niña发展初冬,巴伦支—喀拉海海冰异常增加。EP和CP型El Ni1o对初冬北极海冰的影响类似:格陵兰海海冰异常减少,而哈德逊—巴芬湾海冰异常增加。不同类型ENSO对初冬北极海冰的影响主要通过产生不同的大气遥相关,引起同期和前期的海表气温异常而实现。

Based on the 1951-2019 NCEP/NCAR reanalysis and Hadley Center sea surface temperature and Sea Ice Concentration(SIC)data,the impacts of different ENSOs on the early-winter Arctic sea ice were investigated through composite analysis and atmospheric temperature diagnostic equation.Results show that in the early winter of EP La Niña developing year,the SIC in the Barents-Kara Sea decreases significantly,whereas it increases significantly in the early winter of CP La Niña developing years.On the other hand,the impacts of EP and CP El Ni os are similar:the SIC in the Hudson-Baffin Bay increases significantly,while that in the Greenland Sea ice decreases significantly.Different types of ENSO influence the early-winter Arctic SIC via exciting different atmospheric teleconnections to the Arctic and modifying the local surface air temperatures.