2000-2016年喀喇昆仑-西昆仑山地表温度时空变化特征

Spatial-temporal variation characteristics of LST during 2000-2016 in the Karakoram-West Kunlun Mountains region

为了揭示高寒地区气候变化特征及时空差异性,基于MODIS地表温度(LST)产品,利用气候倾向率、Mann-Kendall非参数检验等多种方法研究了2000—2016年喀喇昆仑-西昆仑山地表温度的时空变化特征及其与海拔和纬度的关系,主要结论如下.(1)2000—2016年喀喇昆仑-西昆仑山LST呈极显著上升趋势,速率为0.32℃/10a(P<0.001),表明该区域对全球变化响应敏感,其中夏季(0.5℃/10a)增温最显著,秋、冬季次之,而春季(-0.096℃/10a)呈降温趋势.(2)空间上,东帕米尔高原以及阿里喀喇昆仑山和西昆仑山东部高海拔区域升温较快;季节上,春、秋两季具有相似性,均呈中部降温、东西两侧升温的空间变化特征,但升温或降温趋势并不显著,夏季,低海拔区(Ⅰ)和高海拔区(Ⅲ)以升温为主,中海拔区(Ⅱ)以降温为主,而冬季呈现与夏季相反的态势.(3)年均地表温度与海拔的偏相关系数为-0.870,呈现出极显著的负相关关系;与纬度的偏相关系数-0.513,呈现出较为显著的负相关关系,说明LST与海拔的关系更为密切.

To reveal the characteristics and spatio-temporal differences of climate change in alpine regions,the temporal and spatial variation characteristics of Karakoram-West Kunlun Mountains region LST during 2000—2016 were studied using linear trend analysis and Mann-Kendall non-parametric test methods,based on the MODIS Land Surface Temperature(LST)products.The results indicate that:(1)LST in the study area showed a significant increasing trend from 2000 to 2016 at a rate of 0.32℃/10a(P<0.001),which indicated that the study area was sensitive to global changes.Among them,the warming trend was most remarkable in summer(0.5℃/10a),followed by autumn and winter,and there was a decreasing trend in spring(-0.096℃/10a).(2)In space,the East Pamir Plateau and Ali Karakoram and the high-altitude area of West Kunlun Mountain experienced rapid warming.In terms of seasonal changes,spring and autumn were similar,which showed a spatial variation of LST in the central part and warming on the east and west side,but the warming or cooling trend was not significant.In summer,the low-altitude areas(Ⅰ)and the high-altitude areas(Ⅲ)were mainly warming.The medium-altitude areas(Ⅱ)were dominated by cooling,while winter presented an opposite trend to summer.(3)The annual average LST had an extremely significant negative correlation with altitude(PCC=-0.870),and a significant negative correlation with latitude(PCC=-0.513),indicating that LST was more closely related to altitude.