北大西洋海温异常影响中东急流的观测分析和数值试验

OBSERVED AND SIMULATED INFLUENCE OF SSTA IN NORTH ATLANTIC OCEAN ON MIDDLE EAST JET STREAM

采用1968—2009年的NOAA Extended Reconstructed Sea Surface Temperature(ERSST)资料、逐月NCEP/NCAR再分析资料以及改进的NCAR CAM3模式,分析了前期12月北大西洋海温异常对1月中东急流的影响。观测分析和数值试验结果表明,前期12月北大西洋关键区海温异常对1月中东急流具有重要影响,当前期12月北大西洋关键区海温为正(负)异常时,1月中东急流减弱(加强);前期12月北大西洋关键区海温异常通过激发下游地区的异常大气波列来影响1月中东急流的变化。

By using NOAA Extended Reconstructed Sea Surface Temperature （ERSST） data from 1968 to 2009, the monthly NCEP/NCAR reanalysis data from 1968 to 2009, and NCAR CAM3 model, this paper studied the influence of sea surface temperature anomaly （SSTA） in North Atlantic Ocean in the preceding December on the Middle East jet stream （MEJS） in January. The observed and simulated results show that there is an obvious response of January MEJS anomaly to the S STA in the key region of North Atlantic Ocean in the preceding December. When the SSTA is positive （negative）, the MEJS will become weaker （stronger） in January. The response of general circulation anomaly to the SSTA in the preceding December can propagate to downstream regions, which induces the MEJS anomaly in January.