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20世纪中叶以来,随着全球变暖加剧,中国冰川普遍发生了退缩,对局地人民生活、生存环境及社会经济产生了深刻的影响,对位于西北干旱区的博格达峰地区尤为突出。本文首先采用趋势分析、突变检验和小波变换等方法对研究区周边气温、降水进行研究,同时应用Landsat 1-4、5、7MSS、TM/ETM+影像分析1972-2013年博格达峰区冰川变化特征,在此基础上系统探讨冰川变化与该区气候变化之间的响应关系。结果表明:11960-2013年研究区气温、降水变化倾向分别为0.19oC/10 a和12.4 mm/10 a;年平均气温在1990年前后存在显著突变,年降水量在1985年前后存在突变。气温主要表现为8~10 a的周期,降水周期性较差。目前处于气温偏高、降水偏少期;21972-2013年冰川面积减少46.71±1.32 km2,年均退缩率为0.66%±0.02%,冰川退缩趋势明显。其中1972-1990年,冰川年均退缩率为0.44%±0.03%;近20年来冰川退缩加剧,年均退缩率达到0.78%±0.09%;3通过分形理论对研究区冰川空间结构特征分析表明,预计未来冰川消融率将趋于稳定,但仍处于较高状态;4对比中国西部各地区冰川的变化,发现该地区冰川退缩和其他区域退缩速率相吻合;51990年之前博格达峰地区冰川变化受温度和降水共同控制,1990年之后冰川退缩主要由气温上升引起。
Since the middle of the 20th century, as global warming intensified, glaciers in China generally retreated, which had a profound impact on local people’s living, living environment and social economy, especially in the Bogda Peak region in the arid region of Northwest China. In this paper, we first studied the temperature and precipitation around the study area by using the methods of trend analysis, mutation test and wavelet transform. At the same time, the Landsat 1-4, 5, 7 MSS and TM / ETM + images were used to analyze the changes of glacier in the Bogda peak area from 1972 to 2013 Characteristics, on the basis of systematic study of glacial changes and climate change in the region of the response. The results show that the trend of temperature and precipitation in the study area from 11960 to 2013 are 0.19 o C / 10 a and 12.4 mm / 10 a, respectively. There is a significant change in annual average temperature around 1990, and the annual precipitation has a mutation around 1985. The main temperature is 8 ~ 10 a cycle, the precipitation cycle is poor. At present, the temperature is high and precipitation is less than normal. The area of glaciers decreased by 46.71 ± 1.32 km2 from 21972 to 2013, with an average annual shrinkage rate of 0.66% ± 0.02%. Glacial retreat tendency was obvious. The average annual retreat rate of glaciers was 0.44% ± 0.03% from 1972 to 1990; glacier retreat intensified in the past 20 years, with an average annual retreat rate of 0.78% ± 0.09%; 3 Based on fractal theory, the spatial structure of glaciers in the study area was analyzed, It is expected that the rate of glacier melting will stabilize in the future but it is still at a relatively high level. 4 Comparing the glacier changes in various areas of western China, it is found that the glacier shrinkage in this area is consistent with the rate of retreat in other areas. Under common control of temperature and precipitation, glacier retreat after 1990 mainly caused by the temperature rise.