1957-2002年北大西洋海表风速时空分布特征及变化周期研究

Analysis of Sea Surface Wind Field in the North Atlantic Ocean from The Year 1957 to 2002

利用来自ECMWF的ERA-40海表10 m风场资料,采用EOF、功率谱等分析方法,对北大西洋海域海表风场的时空分布特征、变化周期等进行分析,研究发现：（1）北大西洋海域海表风场EOF分析的第一模态呈同位相分布,由高纬至低纬表现出＂高-低-高-低＂的分布特征;第二模态在空间分布特征上,北大西洋中部海域与东西两岸表现出反位相分布;第三模态的等值线也表现出东北-西南向,东部海域和西部海域表现出反位相分布特征,（2）北大西洋海域的海表风速在近44年期间整体呈显著的逐年线性递增趋势。在1958年至1967年期间,海表风速的变化趋势较为平缓,1968-1974年期间则表现出一波较为强劲的递增趋势,在1975年至2001年期间表现出缓慢的递增趋势。（3）北大西洋海域的海表风速存在明显的2.0~2.36年、3.71年以及26年以上的长周期震荡。

In this study, the ERA-40sea surface wind data from ECMWF(European Centre for Medium-Range Weather Forecasts) was used to analyze the characteristics of wind field in the North Atlantic Ocean. We use the EOF and Power spectrum methods were used to analyze the temporal and spatial characteristics, periods. Results show that:(1)North Atlantic sea surface wind field of the first mode EOF analysis showed the same phase distribution from high latitudes to low latitudes exhibit'high- low- high- low'distribution characteristics; second mode on the spatial distribution, the central North Atlantic waters and coasts exhibit anti- phase distribution; third-modal contours also showed northeast- southwest to the eastern and western sea waters exhibit anti- phase distribution.(2) North Atlantic sea surface wind speed in the past 44-year period as a whole showed a significant linear increasing trend year by year. In the 1958-1967 period, the trend of sea surface wind speed is more gentle,1968-1974 period showed a relatively strong wave of increasing trend in the 1975-2001 period showed a slow increasing trend.(3)North Atlantic sea surface wind speed obvious 2.0-2.36 years, 3.71 years, and 26 years of long-period oscillation.