西安市降雨模式变化研究

发布时间：2018-03-28 07:22

本文选题：降雨模式　切入点：降雨量变化　出处：《西安建筑科技大学》2015年硕士论文

【摘要】：20世纪80年代以来,西安市进入了快速而稳定的城市化发展阶段,城市规模不断扩大。极端降雨和内涝事件频发,对城市雨水排出设施提出更高要求。近年研究和关注的气候变化热点中,降雨模式特性研究受到较多关注,明确降雨模式变化,对城市雨水排水管网的设计可提供理论支撑。本文收集了西安市1961~2014年共计54年的自记降雨资料,分段统计了年均降雨量及降雨日数、大雨量、暴雨量及其降雨日数、降雨强度、标准化降雨指数SPI和雨型等,对西安市降雨模式进行多时间尺度和趋势分析。主要结论如下:(1)西安市54年年均降雨量整体呈减少趋势,年均降雨日数整体呈减少趋势,降雨日数减少幅度大于降雨量减少幅度,降雨的集中度在增加。大雨最多发生在9月,暴雨最多发生在7月,年均总大雨降雨日数和降雨量、暴雨降雨日数和暴雨量均呈上升趋势,并且降雨量的增加幅度均大于降雨日数的增加幅度。(2)西安市干旱主要以轻旱和中旱为主,1995年之后的干旱主要以中旱为主,轻旱和中旱在7~9月份的发生频率均较其他月份比较低;54年分段年均SPI指数分布趋势与西安市分段年均降雨量变化趋势一致。(3)相同降雨强度,在不同时期重现期不同,同一强度降雨的重现期在近年分段呈下降趋势;在相同重现期条件下,短历时降雨强度呈现共5次先升高后降低的周期变化,历时越短周期变化越明显;短历时和长历时降雨的降雨强度随年份的增加整体呈减少趋势。(4)随着选样年份的增加,西安市60min短历时降雨的降雨过程更趋于缓和,120min的短历时降雨的雨型由双峰型变为单峰型,降雨集中度有变大趋势,且主要集中在5~30 min时段发生。
[Abstract]:Since the 1980s, Xi'an has entered a rapid and stable stage of urbanization. The scale of the city has been expanding. Extreme rainfall and waterlogging have occurred frequently. More attention has been paid to the characteristics of rainfall patterns among the hot spots on climate change that have been studied and paid close attention to in recent years, and it is clear that rainfall patterns are changing. In this paper, the self-recorded rainfall data of 54 years from 1961 to 2014 in Xi'an are collected, and the average annual rainfall and rainfall days, heavy rainfall, storm rainfall and rainfall days, rainfall intensity are counted. Standardized rainfall index (SPI) and rainfall pattern were analyzed in this paper. The main conclusions are as follows: (1) the average annual rainfall in Xi'an is decreasing in 54 years, and the annual rainfall days in Xi'an are decreasing. The number of days of rain decreased more than the amount of rainfall, and the concentration of rainfall increased. Heavy rain occurred most in September, and heavy rain occurred most in July, with the average annual total rainfall days and rainfall. The number of rainstorm days and storm rainfall are both on the rise, and the increasing range of rainfall is larger than that of rainfall days.) drought in Xi'an is mainly light drought and moderate drought, and the drought after 1995 is mainly moderate drought. The frequency of mild drought and moderate drought in July and September were lower than that in other months, and the distribution trend of SPI index in 54 years was the same as that in Xi'an.) the rainfall intensity was the same as that in Xi'an, and the recurrence period was different in different periods. The recurrence period of the rainfall of the same intensity showed a downward trend in recent years, and under the condition of the same recurrence period, the intensity of the short-duration rainfall increased first and then decreased for a total of five times, and the shorter the duration was, the more obvious the change was. The rainfall intensity of short duration and long duration rainfall decreased with the increase of year. 4) with the increase of sample selection year, the rainfall process of 60min short duration rainfall in Xi'an tended to moderate the rainfall pattern of short duration rainfall of 120min from double peak type to single peak type. The rainfall concentration tends to increase, and it mainly occurs in the period of 5 ~ 30 min.
【学位授予单位】：西安建筑科技大学
【学位级别】：硕士
【学位授予年份】：2015
【分类号】：TU992.0

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