Urban effects on the distribution of heavy convective rainfall
Urban effects on the distribution of heavy convective rainfall
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城市对强对流降雨分布的影响
DOI：
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发表时间：
1975
期刊：
影响因子：
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通讯作者：
F. Huff
中科院分区：
文献类型：
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作者：
F. Huff
利用1971-1973年夏季在圣路易斯地区运行的225个5500平方公里范围内的记录雨量站的数据，调查了城市对暴雨分布的潜在影响。主要目的是定量确定无意的天气影响对与城市和郊区下水道设计有关的短时强降雨频率和幅度的影响，以及在应用计划影响天气以缓解农业和城市供水短缺方面的影响。重点分析了(1)雨区，这是在中西部等以雷暴为主的气候中产生强短时率的基本对流单位，以及(2)在网络内产生25毫米或更多降雨量的强暴雨的分布。城市受影响雨量与农村(未受影响)雨量的比较是评估城市效果的主要评估工具。结果显示，与农村(对照)细胞相比，受城市影响的细胞产生的水分明显更多。这种过剩在中强风暴中最为严重，显然最常见的原因是有组织的天气系统中的自然大气降雨过程增强。这场25毫米的暴雨显示，在圣路易斯和奥尔顿-伍德河这两个城市工业区的下风向经常发生的地区，发生的暴雨明显最多。得出的结论是，在大型城市-工业区，暴雨的频率分布在城市、郊区和农村之间可能会有很大差异，这可能需要重新评估当前使用的下水道设计暴雨参数。
Data from a network of 225 recording rain gages in 5500 km2, operated during the summers of 1971–1973 in the St. Louis area, were used to investigate potential urban effects upon the distribution of heavy rainfalls. The primary purpose was to determine quantitatively the effect of inadvertent weather modification upon the frequency and magnitude of short-duration, intense rain rates that are pertinent to urban and suburban sewer design and of concern in applications of planned weather modification to alleviate agricultural and municipal water supply shortages. Emphasis was placed upon analysis of (1) rain cells, the basic convective unit responsible for the production of heavy short-duration rates in thunderstorm-dominated climates, such as the Midwest, and (2) the distribution of heavy rainstorms producing 25 mm or more of rainfall within the network. Comparison of urban-affected and rural (nonaffected) rain cells was the primary evaluation tool in evaluating the urban effect. Results showed a substantially greater water yield from the urban-affected cells compared with that from the rural (control) cells. The excess was greatest in moderate to heavy storms and apparently resulted most often from enhancement of the natural atmospheric rainfall processes in organized weather systems. The 25-mm rainstorms showed a pronounced maximum of occurrence in a region that frequently lies downwind of two urban-industrial areas, St. Louis and Alton-Wood River. It was concluded that the frequency distribution of heavy rainfalls may vary significantly between urban, suburban, and rural areas in large urban-industrial regions and that this may necessitate reevaluation of sewer design storm parameters in current use.