五十年来秦巴山地气候变化趋势及空间分布研究

【作者】 高翔；

【导师】 白红英；

【作者基本信息】 西北大学 ， 自然地理学， 2011， 硕士

【摘要】 秦岭是横亘在我国中部的著名山脉,更是我国气候的重要分界线。本文利用1959-2009年50年来秦岭地区南坡20个站点,北坡13个站点总计33个标准气象站点的逐年月平均气温、降水资料、研究区县界图和1：5万秦岭地区DEM图,利用GIS技术分析研究了50多年来秦岭地区气候变化趋势及秦岭山地气温空间分布特征。其主要研究结果和进展如下：(1)50多年来秦岭地区气温及降水变化趋势50年来秦岭地区年均温呈显著上升趋势,其北坡变暖更为显著,年均温增加达1.2℃,南坡年均温增加达0.5℃。年均温的明显上升发生在1993年。四季气温除夏季呈微弱的减少趋势,两地区春、秋、冬三季平均气温均呈极显著的上升趋势(p<0.01),其中冬、春两季平均气温上升更为显著。秦岭北坡地区四季气温的变化速率与变化幅度均高于南坡,且两地区四季温差均逐渐减少。秦岭南北坡地区1-5月,9-12月气温均呈增加趋势,尤以2,4月和9月增温更为明显,其中北坡增温更为迅速。秦岭南坡地区年降水量呈不显著的减少趋势,北坡地区则呈微弱的增加趋势。秦岭南北坡地区春季和秋季降水量均呈减少趋势,两地区春季降水量均通过了显著性水平检验(p<0.05)；夏、冬两季两地区降水量均呈增加趋势,其中北坡夏季降水量增加显著(p<0.01)。秦岭地区4月降水量呈显著的减少趋势。(2)秦岭山地50多年来年平均气温及1月均温的空间分布特征基于DEM制作了秦岭山地年均温栅格影像图。秦岭地区年平均气温空间分布总体上是南高北低,西部高山地区年均气温较为明显地低于其他地区,低值中心在太白山附近地区,最低值为0.35℃,气温较高的地区为关中平原地区以及陕南的部分地区,气温的最高值为16.25℃。秦岭1959-1969年的1月均温的范围是-11℃～4℃,1979-1989年1月气温范围为-10℃～4℃,最低温度较之前20年上升了1℃此期间秦岭北坡、南坡均出现增温趋势,0℃等温线发生明显上升。至21世纪初(1999-2009)年间,1月均温分布为(10℃～5℃),最低温度和最高温度均比60、70年代增加1℃。(3)50年来秦岭1月0℃等温线变化趋势1月0℃等温线走势与秦岭主脉走向大体一致,50多年来秦岭地区1月零摄氏度等温线有逐渐的北移趋势,利用GIS的空间分析功能按每十年时间顺序提取五条等温线海拔区间范围的均值为别为：1091米、1101米、1127米、1116米、1187米,可以看出等温线五十年间发生了上升,其对应的海拔高度上升约100米左右,尤以近十多年来上升幅度明显。更多还原

【Abstract】 Qinling Mountains is a famous mountain lies in the central of China, and also is the important boundary of climate. The study using the data of annual mean monthly temperatures and precipitation between 1959 and 2009 acquired from 33 standard meteorological sites(20 in south and 13 in north) in the region of Qinling Mountains, and the county bounded map and DEM map of study area. Creating the spatial distribution map of Average annual temperature and January temperature in Qinling Mountains with the help of GIS spatial interpolation technique, and using climate trend rate and climate tendency coefficient method to contrastively analyst the trend of temperature and precipitation in levels year、season and month in past 50 years based on the existing climate data. The main study results and progress as follow:(1) the annual mean temperature in the southern and northern regions tended to significantly increased, and the northern regions warmed more significantly.1993 and 2007 are the turning points of the change of annual mean temperature. Except that summer mean temperature tended to faintly decrease, the average temperature of spring, autumn and winter in both regions showed a very significant increasing trend(p<0.01), which the winter and spring mean temperature increased more significantly. The rate and amplitude of seasonal mean temperature in northern regions were faster and greater than those in southern regions, and the seasonal mean temperature between two regions were gradually reduced. Monthly mean temperature from January to May and September to December in southern and northern regions showed an increasing trend, especially February, April and September warming more significantly, which in northern regions warmed more rapidly.The annual precipitation in southern regions of Qinling Mountains showed a decreasing trend that was not pronounced, while which in northern regions tended to faintly decrease. 2007 was a turning point of annual precipitation in northern regions. The spring and autumn precipitation in Qinling Mountains area showed a decreasing trend, and spring precipitation have passed the significant level test(p<0.05); while the summer and winter precipitation showed an increasing trend, which the summer precipitation in northern regions increased significantly(p<0.01). The monthly precipitation of March and April in southern regions of Qinling Mountains significantly reduced; while April precipitation was a significant upward trend and June precipitation has a significant decreasing trend in northern regions.(2) The spatial distribution features of annual mean temperature and January average temperature in Qinling area:The distribution of annual average temperature in Qinling Mountains area is greatly influenced by topography in past 50 years. The spatial distribution of annual mean temperature in Qinling Mountains area is generally present that southern higher than northern. annual mean temperature of the western mountain region is obviously lower than others parts, the center of low temperature lies in the vicinity of Taibai Mountain and the minimum value is 0.35℃; the temperature of Guanzhong plain and parts of Shannan regions is higher than other parts, and the maximum value is 16.25℃. we can show that the temperature of Guanzhong region is higher than Shannan region’s by the distribution of temperature.The temperature of Qinling Mountains in January ranged from-11℃to 4℃between 1959 and 1969, the high temperature areas were most concentrated in Shannan regions, and Taibai Mountain area was the center of low temperature.0℃isotherm trend in January was broadly consistent with the run of Qinling Mountains’s main vein. The range of temperature in January between 1969 and 1979 was roughly same as that in past 10 years, but there was a small increase in temperature in Guanzhong regions and the range was wide. The temperature in January ranges from-10℃to 4℃between 1979 and 1989, there were a increase trend in temperature in both the southern and northern slope of Qinling Mountains during this period, and the 0℃isotherm was clearly run north, the spatial distribution of temperature between 1989 and 1999 was same as that. The range of increase in temperature is obvious (10℃—5℃)between 1999 and 2009, especially in the valley region of northern slope, the temperature has significanted increased, and was higher than the temperature of the peak with same latitude.(3) Correspondence of 0℃isotherm and elevation in Qinling Mountains in January in past 50 yearsThe 0℃isotherm in January was gradually run north in past 50 years,the average elevation of 5 isotherm in chronological respectively were 1091 meters、1101 meters、1127 meters、1116 meters and 1187 meters, we can show that isotherm was run north in past 50 years, and the corresponding elevation also had a increase trend.更多还原