摘要
特大暴雨的成因和预测 ,至今仍是世界性科学难点之一。然而 ,我们运用内外因耦合方法 ,对 1998年长江发生的 6次持续性大暴雨到特大暴雨过程 ,事先比较准确地报出了其中 5次。特大暴雨的内外因耦合的原理是 :特大暴雨必须在暴雨天气形势基本具备情况下 ,与月亮奇异位置时的非线性引力效应及其引潮力共振减压的触发相耦合而引起。两者缺一不可 ,其机理是 :引潮力共振减压是在暴雨区上空施加一个异常的提升力 ,加强暴雨区的上升运动 ,引起水汽凝结潜热加速释放 ,形成中尺度系统 ,并且通过多次正反馈 ,导致暴雨区水汽凝结潜热的强烈释放 ,从而形成特大暴雨。由于引潮力共振严格取决于月亮奇异位置的发生时刻 ,即它是瞬时的和突然发生的 ,因而特大暴雨往往属于突发性的非线性现象是不足为奇的。
The causes and prediction of the torrential rains is still a well-known challenge in the world today. But used the coupling method of internal and external factors, we have accurately predicted five ones of the whole 6 ones which is the continued heavy rainstorms or torrential rains in the Yangtze River during 1998. For example, at most desperate juncture of fight a flood in the Yangtze River, on August 11 we forecasted that on August 11 and from August 13 to 15 there would be continuous heavy rainstorms from the east of Sichuan Province to the west of Hubei Province, and on August 19 to 20 would be continuous torrential rains in Sichuan Basin. They all were proved to be true. The coupling principle of internal and external factors of the torrential rains is that: the torrential rain is a complex system of nonlinear and sudden changed, it needs be processed as open system. Our research indicate that the torrential rain must be the based on synoptic situation of rainstorm, and coupled with the nonlinear gravitational effect and its decompression of tide-generating force resonance(TGFR) at the time of lunar strange position. Neither can be neglected. The mechanism both of them is that: the decompression of TGFR impose on a abnormal promoted force, reinforced the rising motion of the rainstorm area, rising the speed up release of condensational latent heat, forming the mesoscale system, and through much time positive feedback, bring about strong release of condensational latent heat, thus creates the torrential rains. Owing to the TGFR strongly depends on the happened time of lunar strange position, namely it is instantaneous and sudden changed, thus we are not surprised that the torrential rains frequently belong to sudden changed and nonlinear phenomenon.
出处
《地球信息科学》
CSCD
2001年第2期53-59,共7页
Geo-information Science
基金
国家科技部攀登-特别支持费
联合国"减灾科学与公共管理相结合"全球计划资助
