Presumed Little Ice Age glacial extent in the eastern Tian Shan, China

Mountain glaciers across the Tian Shan provide critical freshwater resources for the arid and semi-arid areas in Central Asia. Glacial extent during the Little Ice Age (LIA) has been investigated in individual valleys, but its spatial characteristic across a large region still remains unclear. We delineated the presumed maximum LIA glacial extents in three study regions of the eastern Tian Shan (the Boro-Eren, the Bogeda, and the Barkol-Karlik ranges) using Google Earth and the 30 m Shuttle Radar Topography Mission digital elevation model. The corresponding contemporary glaciers were extracted from the Second Glacier Inventory Dataset of China. The total area of 865 contemporary glaciers was estimated to cover 791.6 km2 during a LIA Maximum and decreased to 484.6 km2 around 2006–2010, with a relative area loss of 38.8%. The spatial pattern of glacier area loss exhibits a west–east decreasing trend between these three regions. This map provides a data set to investigate the pattern of LIA glacial extents and assess climate impact on water resources in the eastern Tian Shan at a centennial time scale.

横贯天山（Tian Shan）的山地冰川为中亚干旱与半干旱地区提供了至关重要的淡水资源。此前已有研究针对单个山谷开展了小冰期（Little Ice Age，LIA）冰川范围的调查，但大区域尺度下的空间分布特征仍不明确。本研究借助Google Earth与30米分辨率航天飞机雷达地形测绘任务（Shuttle Radar Topography Mission，SRTM）数字高程模型，对天山东段三个研究区（博罗埃伦山脉、博格达山脉、巴里坤-卡尔里克山脉）推定的小冰期最大冰川范围进行了勾绘。对应的现代冰川源自中国第二次冰川编目数据集（Second Glacier Inventory Dataset of China）。研究区内的865处现代冰川，在小冰期鼎盛时期的总面积达791.6平方千米，至2006-2010年左右缩减至484.6平方千米，相对面积损失率达38.8%。三个研究区的冰川面积损失空间格局呈现自西向东递减的趋势。本数据集可为百年尺度下探究天山东段小冰期冰川分布格局、评估气候变化对水资源的影响提供数据支撑。