【作者】 王雅强；

【导师】 吴正方；

【作者基本信息】 东北师范大学 ， 自然地理学， 2006， 硕士

【摘要】 气候作为人类赖以生存的自然环境的一个重要组成部分,它的任何变化都会对自然生态系统以及社会经济产生影响。气候变化的影响将会是多尺度和多层次的,气候作为一种重要的自然资源,同时作为自然环境的重要组成部分,从两个不同的方面在社会经济系统中发挥作用。气候变化将会不同程度地影响到全球和各地区社会经济等多方面,人类社会系统对气候变化的敏感性和脆弱性,随其地理位置、时间、社会经济发展水平和环境条件而变化,所以应该加强区域气候变化及其影响的研究,了解本区气候变化特点,这对于制定区域发展政策、进行生态建设将起着重要指导作用。本文以吉林省西部地区的五个县市,即白城、通榆、前郭、乾安和长岭为研究区域,利用五个站点的1951-2003年逐日降水数据,结合气象学和水文学的知识,利用MATLAB6.5的小波分析功能,Visual FoxPro6数据库、SPSS统计分析软件、EXCEL以及统计学的相关理论对该区夏季降水的多年平均状况和暴雨的时空分布规律做出了一些有意义的探讨,并根据暴雨的时空分布规律的研究成果提出了相关的抗洪防洪措施。该区属于半干旱生态脆弱区,研究夏季降水特征对于做好工农业生产有很大帮助。该区气候的显著特点是降水不足,年际降水时空分布不均,夏季多雨,且多以暴雨、阵雨的形式降落,形成洪水流走,暴雨过后常发生干旱。正是由于年际降水量分配不均,使年内旱、涝灾害相间发生,但旱灾要远远严重于涝灾,基本上是十年九旱,也正是因为如此,长期以来防洪意识疏忽,缺少防洪措施,致使在暴雨洪水来临时损失严重。因此找出本区降水的变化规律,为防洪做出理论上的依据是非常必要的。目前国内对吉林省西部地区做出的成果多数是研究本区干旱治理,对于降水的均值及极端降水事件即暴雨的研究还很少。论文统计及研究结果表明:半个世纪以来该区夏季平均降水量为301mm,降水总趋势是稳中有降,年内降水以7月最多,空间上以位于最南部的长岭降水最多,最西部的白城降水最少。50年代、60年代、80年代为相对多雨期,70年代和90年代为少雨期,未来短时间内仍以旱灾为主,但是洪灾也不可忽视。从五个站点以及整个西部的小波分析图看出夏季降水均表现出明显的准22年多雨少雨长周期振荡以及11—12年较长周期震荡,这与太阳黑子活动的双周期和单周期恰好吻合,这也验证了太阳黑子双周期为自然灾害多发期这一说法。在长周期中又有3年左右的甚低频波动;且各个尺度的周期都有变短的趋势。从22年尺度看,该区的两个多雨期分别是1960-1973年和1987-2000年,1959年之前、1974-1986和2001年之后为三个干旱期,而目前正处于长周期内的少雨时期,干湿期变化有四个突变点,分别是1959年、1973年、1986年和2000年。从11-12年尺度看,目前也处于少雨期,所以今后11-12年内该区仍应做好抗旱工作。更多还原

【Abstract】 As an important component of the nature environment, climate is vital to human survival.Every change of the climate can make an effect on nature eco-system and social economy.The effect will be multi-scale and multi-level. As an important nature resource, also climate isthe main component of nature environment. Therefore the effect on social economy systemwill be from two aspects. At different degrees, climate-change has an effect on every aspect ofglobal and regional social economy. Varying with the location, time, society developmentlevels and the environment condition, the social system is sensitive and vulnerable toclimate-change. Thus the study on regional climate change and its character should bereinforced. It is vital to the making of region development policy and the eco-construction.Taking five stations in the west of Jilin province as study area, they are Baicheng、Tongyu、Qianguo、Qian’an and Changling. Making use of their daily precipitation databetween 1951-2003, combining the knowledge of aerography and hydrology, using thewavelets function of MATLAB6.5、Visual FoxPro6 data-base、SPSS、EXCEL and thestatistics theory to do some significative discussion on the long time average status of summerprecipitation and the Temporal and spatial distribution rule, then pointing out interrelatedmeasures of controlling flood based on the results of Temporal and spatial distribution rule.This study area is semi-drought eco-frailty area, the research of summer precipitationcharacteristic is much helpful to industry and agriculture production. The evidentcharacteristic of climate in this area is inadequate precipitation, odds temporal and spatialdistribution, and rainy summer, but usually falling as rainstorm or shower, and then flowing asflood, drought usually happen after rainstorms. Just because of the odds temporal and spatialdistribution, drought and flood happen usually, but drought is much heavier flood, almost 9times in 10 years, just because of this, in a long period the consciousness of control flood is soweak and there is a lack of flood control measures that the loss is heavily when the flood iscoming. So finding out the variation rule of precipitation and making theory base for flood isvery necessary. At present, the research fruit of this area is almost about drought father, butthe research about the average status and extreme status such as rainstorm of precipitation isstill infrequent.The research and statistic results of this paper reveals: in the latest century, the averageprecipitation of summer is 301mm and the trend is decreasing steadily, the precipitation inJuly is the most, as to space Changling is the most which is southmost, Baicheng is the leastwhich is westmost. 1950s、1960s and 1980s are relatively rainy time, 1970s and 1990s arerainless time, in the future years drought is still the archenemy, but flood also can’t beneglected.We can see from the wavelets maps of the five stations and the whole west: summerprecipitation has obvious 22year rainy-rainless long cycle surge and 11-12year less longercycle surge, it is just coincident with the double cycle and single cycle of macula activity, italso validates the fact that natural disaster is much more in macula double cycle. During thelong cycle, there is low frequency wave of 3year and every cycle has the trend of shorten.From the 22 cycle, we can see the two rainy time are 1960-1973 and 1987-2000,before 1959,1974-1986 and after 2001 are the three drought time, and now we are on rainless time of longcycle, the four break dot of change from dry to wet are 1959、1973、1986 and 2000. From the11-12year cycle we can see nowadays is also on rainless time, so in the coming 11-12 yearswe still should pay attention to drought control in this area.According to the factual status of the study area, we establish the precipitation whichover 45mm per day as the rainstorm standard and over 100mm per day as severe rainstormstandard. The knowledge of probability theory reveals: in the half latest century, both thenumber and the quantity of rainstorm is decreasing, however, the quantity of severe rainstormhas biggish increase, in the five stations Changling has the most rainstorm and Qianguo hasthe least, the distribution of rainstorm in a year is completely consistent with precipitation. Inthe whole west area the frequency of rainstorm is 4.69time per year, the probability ofhappened rainstorm in a year reaches 96%, in the 53 statistical years only 1952 and 2002 hasno rainstorm. The probability of happened severe rainstorm in a year is 19%. In the sevengrades of rainstorms the one of 50-60mm is the most frequent, about 1.52time per year. Thereare many rainstorms in this study area, that is about 225 times, but not every rainstorm canbring flood, it is also according to the former base water level and the concrete status, so if wedo the control flood measure well, even the flood is coming, the situation of a disaster alsocan be artificial knocked-down.更多还原