Glacier changes in the Qaidam Basin from 1977 to 2018

• 作者: SuGang Zhou XiaoJun Yao Yuan Zhang DaHong Zhang Juan Liu HongYu Duan
• 来源期刊: 寒旱区科学（英文版）
• 年，卷（期）: 2020,（6）
• 所属期刊栏目: Articles
• 页码范围: 491-502
• 页数: 12页
• 语种: 英文

摘要

Based on Landsat MSS/TM/OLI remote sensing images, glaciers vector data in the Qaidam Basin were extracted for 1977, 2002, and 2018, and their spatial-temporal variations were analyzed. Results show that there were 2, 050 glaciers covering an area of 1,693.54±40.96 km2 and having an ice volume of 108.65±2.43 km3 in the Qaidam Basin in 2018. Gla-ciers with areas <1.0 km2 accounted for the largest number, while glaciers with areas of 1.0-5.0 km2 accounted for the most glacierized area. In the past 50 years, the number of glaciers decreased by 177, and the glacier area and volume re-duced by 338.08 km2 (-8.12 km2/a) and 19.92 km3 (-0.48 km3/a), respectively. Retreat altitudes of glaciers were concen-trated at 4, 900-5, 600 m, 4, 700-5, 200 m, and 5, 000-5, 600 m and reduced areas accounted for 95.53％, 77.80％, and 69.19％in the Kunlun, Qilian, and Altun mountains, respectively. The area of north-oriented glaciers decreased the most (-125.43 km2), but the west-and east-oriented glaciers retreated at the fastest rate (i.e.,-27.11％and-27.10％). All gla-ciers showed a decreasing trend in sub-regions of the Qaidam Basin from 1977 to 2018. The decreasing trend was acceler-ated gradually from northwest to southeast in the northern part of the basin, while glacier change was the smallest in the middle section and gradually accelerated towards both ends of the basin's southern part. The temperature had continued to rise, and the precipitation had increased slowly in the Qaidam Basin during the past 50 years. The continuous rise in air temperature was the main reason for the retreat of glaciers.