【作者】 徐文明；

【导师】 孙照渤；

【作者基本信息】 南京信息工程大学 ， 气象学， 2006， 硕士

【摘要】 利用NCEP/NCAR提供的月平均潜热通量场、海平面气压场、高度场和风场资料,NOAA提供的海温场资料,以及我国160站气温资料,对太平洋的潜热通量和我国气温进行统计诊断分析。 潜热距平场的EOF分析表明,秋冬季最主要的空间分布为黑潮及其延伸体处与赤道中东太平洋的反位相特征;春夏季为澳大利亚以东与赤道中东太平洋的反位相特征。其时间系数在近55年来都有显著的下降趋势,且在70年代中期左右都发生了突变。 在年代际时间尺度上,冬季太平洋潜热在1975/1976发生突变,突变后,在黑潮及其延伸体处的海洋向大气输送潜热,沿赤道太平洋大气向海洋输送潜热,同时,欧亚大陆的海平面气压场为“南高北低”的形势,西伯利亚高压强度减弱,500hPa,乌拉尔山处的脊减弱,东亚大槽也减弱,我国上空的850hPa为偏南风。我国的冬季气温增暖,且北方地区的增温明显大于南方。突变前与之相反。 在年际时间尺度上,当冬季黑潮及其延伸体处大气向海洋(海洋向大气)输送潜热,东北太平洋海洋向大气(大气向海洋)输送潜热时,东北地区气温下降(上升),而华中华南地区气温上升(下降)。另外,在太平洋潜热场处于不同的年代际背景下,它与大气环流和我国气温之间的年际变化关系存在很大的差异。在太平洋潜热场突变以前,潜热在赤道太平洋,为正(负)距平。东西伯利亚高压和阿留申低压都减弱(增强),东亚大槽北部加深(减弱),南部减弱(加深),在我国东北地区为偏北(南)风,气温下降(上升),华南地区为偏南(北)风,气温上升(下降)。此外,海温场主要表现为赤道中东太平洋的增暖(变冷),但该地区的海温与我国冬季气温的关系并不显著。在太平洋潜热场突变以后,潜热在黑潮及其延伸体处为负(正)距平,东北太平洋为正(负)距平。西伯利亚高压和阿留申低压都减弱(增强),东亚大槽北部加深(减弱),南部减弱(加深),乌拉尔山处的脊减弱(加强),我国东部沿海和河套地区为很强的偏南(北)风,气温上升(下降)。此外,海温场同样表现为赤道中东太平洋的增暖(变冷),而它与我国冬季气温存在了关系显著的区域。更多还原

【Abstract】 Based on the latent heat flux, sea level pressure, height and wind monthly mean data from NCEP, the sea surface temperature data from NOAA and the air temperature data in 160 stations in China, the latent heat fluxes over the Pacific ocean and the air temperature in China were examined.The latent heat anomalies are analyzed by using EOF method. It is found that the 1st modes describe the contrary phrase of Kuroshio Extension and the equatorial mid-east Pacific Ocean in winter and fall, and the contrary phrase of the east of Australia and equatorial mid-east Pacific ocean in spring and summer. The time series show that there are declines during the recent 55 years and abrupt in the middle of 1970’s.In the decadal scale, there is an abrupt in 1975/1976 for the latent heat over the Pacific Ocean in winter. After the abrupt, the ocean releases latent heat in Kuroshio Extension, while the ocean gets latent heat in the equatorial mid-east Pacific Ocean. At the same time, the SLP over the Europe-Asian continent is ’south high north low’ mode, the Siberian High becomes weaker, the ridge over the Ural mountain becomes weaker, so does the East Asian Trough, and over China the wind is from south. The winter air temperature in China rises up, and the changing extent is larger in North China than in South China, and vice versa.In the annual scale, the winter air temperatures in the northeast of China rise up, while the air temperatures in the middle of China and South China go down, when the ocean gets latent heat in Kuroshio Extension and releases latent heat in the northeast of the Pacific ocean, and vice versa. In addition, the annual connections among the latent heat flux over the Pacific Ocean, the air cell and the winter air temperature in China are different, under different decadal backgrounds. Before the abrupt, the latent heat anomaly is positive in the equatorial Pacific Ocean, the East Siberian High and the Aleutian Low become weaker, the north range of the East Asian Trough strengthen and the south range weaken, and so the prevalent wind is from north in northeast of China, where the air temperature goes down, while the prevalent wind is from south in South China, where the air temperature rises up. Additionally, SST becomes warmer in the equatorial mid-east Pacific Ocean, while its linkage to the winter air temperature is not prominent. After the abrupt, the latent heat anomaly is negative in the Kuroshio Extension and positive in the northeast of the Pacific Ocean, the Siberian High and the Aleutian Low weaken, the north range of the East Asian Trough strengthen and the south range weaken, the ridge over the Ural mountain weaken, and so the prevalent wind is from south in the east of China and HETAO area, where the air temperature rises up. In addition, SST becomes warmer in the equatorial mid-east Pacific Ocean, and its linkage to the winter air temperature is prominent.更多还原