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对汉江上游与黄河中游晋陕峡谷公元1800a以来发生的大洪水事件进行统计与对比分析。结果表明:1)历史时期汉江上游大洪水发生频率高于晋陕峡谷。1920a以后,随着全球气候变暖,汉江上游和黄河中游大洪水都有发生频率增大、间隔年份缩短的趋势。2)受副高边缘到达时间差异的影响,汉江上游大洪水时间过程呈“M”型;晋陕峡谷大洪水时间过程呈“A”型。3)影响两地降水的环流形式相似,但水汽的主要来源有所不同。在汉江上游,水汽来源既有东南季风也有西南季风带来的暖湿气流;在黄河中游,东南季风带来的水汽是降水的主要来源。两地降水多少及大洪水的发生时间、强度与频次,受到东南季风、西南季风强弱及其组合情况的共同影响与控制。
Statistics and comparative analysis were made on the major floods that occurred since 1800 a in the upper reaches of the Hanjiang River and the middle reaches of the Yellow River and the Shanxi-Shaanxi Gorge. The results show that: 1) The frequent floods in the upper reaches of the Hanjiang River during the historical period are higher than those in the Jin-Shaan Canyon. After 1920a, with the global warming, the floods in the upper reaches of the Han River and the middle reaches of the Yellow River have increased in frequency and shortened in the interval. 2) Under the influence of the difference of edge arrival times of the subtropical high, the time course of the major flood in the upper Hanjiang River was “M” type; the time course of the major flood in the Jin-Shan Gorge was “A” type. 3) The circulation patterns affecting the precipitation in both places are similar, but the main sources of water vapor are different. In the upper reaches of the Hanjiang River, the source of water vapor is both warm and humid currents from the southeast and southwest monsoons. In the middle reaches of the Yellow River, the water vapor from the southeast monsoon is the main source of precipitation. The amount of rainfall and the time, intensity and frequency of major floods in both places are jointly affected and controlled by the strength of the southeast monsoon and its combination.