【摘要】 应用气象资料,卫星、雷达资料及带通滤波方法,分析了引发云南德宏州2004-07-05特大山洪泥石流灾害的天气成因。结果表明,除了德宏州区域地质、地貌等自然原因外,德宏州入汛提前,入汛后多低温阴雨是造成这次灾害的前期气候背景;中尺度辐合天气系统、充沛水汽输送及辐合、低空急流的作用导致07-04T20～07-05T20发生特大暴雨,是引发此次山洪泥石流灾害的直接天气原因。更多还原

【Abstract】 Applied meteorological data, satellite infrared pictures, radar echo and the band-pass filter methodology, the synoptic causes for great flash flood and debris flow on July 5, 2004 in Dehong Prefecture of Yunnan Province is studied. The results indicated that the former climatic features, mesoscale synoptic system, water vapour transportation and convergence, as well as low tropospheric jet are the main direct meteorological causes besides the geological and geomorphological causes, for the flash flood and debris flow occurring in Dehong Prefecture on July 5, 2004. In 2004, the flood period of Dehong Prefecture began earlier 10 days than usual, the rainy season started on May 11. The lower-temperature and rainfall days are much more. The low tropospheric jet was formed at 08BST July 5 and the biggest wind speed is above 14 m/s. The biggest wind speed is lower 11 m/s at 20BST July 5, the low tropospheric jet disappeared. The duration of the low tropospheric jet is accordant with heavy storm in Dehong Prefecture（at 08BST～20BST July 5）. The 700 hPa water vapour flux increased abruptly when heavy storm took place at 08BST July 5, the central value added to above 16 g.cm^-1.hPa^-1·s^-1, and there is stronger water vapour convergence in Dehong Prefecture. The abundant water vapour transportation and convergence were important conditions to trigger this flash flood and debris flow occurring in Dehong Prefecture on July 5, 2004. These unusual meteorological phenomenon is one of important aspects for triggering the mountain hazards. On the other hand, satellite infrared and radar echo pictures can clearly reflect mesoscale synoptic system and its evolutive characteristics. The satellite infrared and radar echo pictures will play important role in the close forecast of flash flood and debris flow in the future.更多还原