藏西北高原郭扎错湖泊面积变化与气候响应分析

高原内陆湖泊以其对气候变化敏感的指示作用,常用于分析区域气候变化趋势,为气候预报预测、生态气象服务等提供科学的数据支持。笔者基于1975年郭扎错地形图、1992—2018年TM/ETM+和GF1-WFV等卫星遥感影像资料,对郭扎错湖泊信息进行提取,并分析该湖近40年时空异质性以及面积变化与气候响应之间的关系,主要得出以下结论：（1）40年来郭扎错湖泊面积波动式萎缩,萎缩了3.22 km²,萎缩率为1.30%,其中2006—2019年间萎缩最为明显,从空间上来看主要变化区域在甜水河和崇测河入湖口处;（2）湖泊面积和年平均气温变化综合反映出20世纪90年代以前该区域气候趋势表现为暖湿化,随后趋于暖干化;（3）年平均气温是湖泊萎缩的主要影响因素,年平均降水量滞后性影响冰川,从而间接作用于湖泊面积变化,年平均蒸发量对湖泊面积剧变响应较为明显。

Climate Response for Gozhacuo Area Change in Northwest Tibetan Plateau

Plateau inland lakes, as an indicator of their sensitivity to climate change, are often used to analyze the trend of climate change in this region, providing scientific data support for climate prediction and ecological meteorological services. Based on the 1975 Guozhacuo topographic map, TM/ETM+ in 1992 to 2018 and satellite remote sensing image data, the spatial and temporal heterogeneity in recent 40 years and the lake area with climate response were analyzed. The results showed that (1) Guozhacuo area was shrinking in a fluctuant way, by 3.22 km² with the rate of 1.30%, and the shrinking area mainly located in the outlet of Tianshui River and Chongce River; (2) the change of lake area and annual average temperature comprehensively reflected that the climate trend of the region before the 1990s was warm and wet, then changed to warm and dry; (3) the annual average temperature was the main influencing factor for the shrinking of the lake, the hysteresis of the annual average precipitation affected the glacier, and then indirectly influenced the lake area, and the annual average evaporation change responded obviously to the significant variation of the lake area.