基于信息熵的华北地区降水时空变化研究

发布时间：2018-03-25 16:02

本文选题：信息熵　切入点：华北　出处：《北京建筑大学》2017年硕士论文

【摘要】：半个世纪以来,华北地区工农业迅速发展,人口快速增长,严重加剧了水资源的紧张程度。因此,分析华北区域水资源特征,深入探索华北地区降水时空变化特征,对辅助区域水资源管理具有较大的现实价值。本文选取华北地区作为研究区域,以该区域21个雨量站点1960~2011年逐日降水资料为分析对象,以分析华北地区近50年降水时间和空间维度变化特征为研究目标,探索信息熵方法在水文科学研究中的应用潜力,期望为区域水资源管理、干旱预警等提供辅助决策支持。本文首先对国家气象中心提供的逐日降水资料进行数据预处理操作,根据信息熵理论,利用直方图法进行信息熵和互信息熵等的计算。然后结合模糊聚类分析方法,对华北地区进行分区研究。最后根据无序指数研究该区域降水在时间与空间上的变化。本文研究得出如下成果:1)利用信息熵理论和模糊聚类分析方法将华北地区划分为4个相异性显著的子区域,划分方法符合信息科学原理,具有较高的可靠性。2)华北地区整体的年降水量相较于春、夏、秋、冬四季具有最小的变异性;华北地区西北部年降水的变异性最小,而山东省境内降水的变异性较大。3)华北地区降水的年际变化中月尺度大于季尺度大于年尺度,且各月的降水变化差异较大。分季节讨论的话:春季大部分站点有较小的年际变化,其中4月份的年际变化最大;夏季中8月份的年际变化最大;秋季中11月份的年际变化最大;冬季大部分站点均表现出较大的年际变化,其中1月份的最大。4)华北地区年降水量和降水天数在不同月份分布不均匀的年际变化特征相似。综合考虑降水量和降水天数的月份分配不均匀性,发现1988年我国的降水有明显异常变化。5)华北地区降水量和降水天数的年代际变化一致。受东亚季风的年代际调整影响,华北地区降水60年代中期到70年代中期降水持续减少,到70年代末降水有所转折。6)熵理论可以有效的应用到区域降水时空变化特征分析中,为区域水资源管理与保护、干旱预警等提供辅助决策支持。
[Abstract]:In the past half century, the rapid development of industry and agriculture and the rapid growth of population in North China have seriously aggravated the degree of water resources tension. Therefore, the characteristics of water resources in North China are analyzed, and the characteristics of temporal and spatial variation of precipitation in North China are deeply explored. This paper selects North China as the research area, and analyses the daily precipitation data of 21 rainfall stations from 1960 to 2011. Based on the analysis of spatial and temporal characteristics of precipitation in North China in the past 50 years, the potential of applying information entropy method to hydrological science is explored, which is expected to be regional water resources management. In this paper, we preprocess the daily precipitation data provided by the National Meteorological Center, and according to the information entropy theory, we carry out the data preprocessing operation on the basis of the theory of information entropy. The information entropy and mutual information entropy are calculated by histogram method. Finally, the temporal and spatial changes of precipitation in North China are studied according to the disorder index. The following results are obtained in this paper: 1) using the information entropy theory and fuzzy clustering analysis method, the precipitation in North China is studied. Divided into four distinct subregions, The division method accords with the principle of information science and has high reliability. 2) the annual precipitation in North China is the smallest variability compared with spring, summer, autumn and winter, and the annual precipitation variability in northwestern North China is the least. However, the variability of precipitation in Shandong Province is greater. 3) the interannual variation of precipitation in North China is larger than the seasonal scale, and the monthly scale is larger than the annual scale. The variation of precipitation varied greatly from month to month. If we discuss every season, there is a small interannual variation in most stations in spring, in which the interannual variation in April is the largest, and the interannual variation in mid-summer and August is the biggest. The interannual variation was the largest in mid-autumn and November, and the interannual variation was significant at most sites in winter. The annual precipitation and the number of days of precipitation in North China are similar in different months, and the monthly distribution of precipitation and the days of precipitation are not uniform considering the monthly distribution of precipitation and precipitation days. It is found that the precipitation in China in 1988 has obvious anomalous variation. 5) the interdecadal variation of precipitation and precipitation days in North China are consistent. Due to the Interdecadal adjustment of the East Asian monsoon, precipitation in North China has been decreasing continuously from the mid-1960s to the mid-1970s. By the end of 1970s, the theory of entropy can be applied to the analysis of temporal and spatial variation of regional precipitation effectively, which can provide auxiliary decision support for regional water resources management and protection, drought early warning and so on.
【学位授予单位】：北京建筑大学
【学位级别】：硕士
【学位授予年份】：2017
【分类号】：P426.6

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