《《Interpretation of recent trends in Antarctic sea ice concentration》.pdf

Interpretation of recent trends in Antarctic sea ice concentration Lejiang Yu Zhanhai Zhang Mingyu Zhou Shiyuan Zhong Donald H. Lenschow Zhiqiu Gao Huiding Wu Na Li Bo Sun Downloaded from SPIE Digital Library on 11 Dec 2011 to 07. Terms of Use: /terms Interpretation of recent trends in Antarctic sea ice concentration Lejiang Yu,a,b Zhanhai Zhang,b Mingyu Zhou,b Shiyuan Zhong,c Donald H. Lenschow,d Zhiqiu Gao,e Huiding Wu,b Na Li,b and Bo Sunb a Nanjing University of Information Science Technology, Applied Hydrometeorological Research Institute, Nanjing 210044, China b Polar Research Institute of China, 451 Jinqiao Road, Shanghai 200136, China yulegiang@ c Michigan State University, East Lansing, Michigan 48824 d National Center for Atmospheric Research, Boulder, Colorado 80305 e Chinese Academy of Sciences, Institute of Atmospheric Physics, Beijing 100029, China Abstract. We investigate seasonal trends in sea ice concentration and the relative contributions of the Antarctic Oscillation (AAO), the Pacific-South American two modes (PSA1 and PSA2), and the El Nino-Southern Oscillation (ENSO). The summer range of the trend in the Antarctic ˜ sea ice is the largest, from −83.8% to 59.6% per 29 yr over the period of 1979 through 2007, while the autumn range is the least, from −49.7% to 39.6% per 29 yr for the period of 1979 through 2007. In autumn, among the four indices the largest contribution to the trend in sea ice is the AAO; in winter the ENSO and the PSA1 are better than the other two indices; during spring and summer a change of more than 15% per 29 yr is associated with PSA1. No matter the season, the spatial pattern of the residual trend is similar to that of the total trend; moreover, the