{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,4,13]],"date-time":"2026-04-13T15:04:20Z","timestamp":1776092660344,"version":"3.50.1"},"reference-count":49,"publisher":"MDPI AG","issue":"23","license":[{"start":{"date-parts":[[2021,12,4]],"date-time":"2021-12-04T00:00:00Z","timestamp":1638576000000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"the Strategic Priority Research Program of the Chinese Academy of Sciences","award":["XDA20060201, XDA19070302"],"award-info":[{"award-number":["XDA20060201, XDA19070302"]}]},{"DOI":"10.13039\/501100001809","name":"the National Natural Science Foundation of China","doi-asserted-by":"publisher","award":["41501069"],"award-info":[{"award-number":["41501069"]}],"id":[{"id":"10.13039\/501100001809","id-type":"DOI","asserted-by":"publisher"}]},{"name":"the Second Tibetan Plateau Scientific Expedition and Research Program","award":["2019QZKK0201"],"award-info":[{"award-number":["2019QZKK0201"]}]},{"name":"the Natural Science Basic Research Program of Shaanxi","award":["2021JQ-451"],"award-info":[{"award-number":["2021JQ-451"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Remote Sensing"],"abstract":"<jats:p>Glaciers in the Qilian Mountains, China, play an important role in supplying freshwater to downstream populations, maintaining ecological balance, and supporting economic development on the Tibetan Plateau. Glacier snowline altitude (SLA) at the end of the melt season is an indicator of the Equilibrium line altitude (ELA), and can be used to estimate the mass balance and climate reconstruction. Here, we employ the height zone-area method to determine the SLA at the end of the melt season during the 1989\u20132018 period using Landsat, MODIS (Moderate Resolution Imaging Spectroradiometer) SLA and Shuttle Radar Topography Mission (SRTM) digital elevation model (DEM) data. The accuracy of glacier SLA obtained in 1989\u20132018 after adding MODIS SLA data to the years without Landsat data increased by about 78 m. The difference between the remote-sensing-derived SLA and measured equilibrium line altitude (ELA) is mostly within 50 m, suggesting that the SLA can serve as a proxy for the ELA at the end of the melt season. The SLA of Qiyi Glacier in the Qilian Mountains rose from 4690 \u00b1 25 m to 5030 \u00b1 25 m, with an average of 4900 \u00b1 103 m during the 30 year study period. The western, central, eastern sections and the whole range of the Qilian Mountains exhibited an upward trend in SLA during the 30 year study period. The mean glacier SLAs were 4923 \u00b1 137 m, 4864 \u00b1 135 m, 4550 \u00b1 149 m and 4779 \u00b1 149 m for the western, central, eastern sections and the whole range, respectively. From the perspective of spatial distribution, regardless of the different orientation, grid scale and basin scale, the glacier SLA of Qilian Mountains showed an upward trend from 1989 to 2018, and the glacier SLA is in general located at a comparably higher altitude in the southern and western parts of the Qilian Mountains while it is located at a comparably lower altitude in its northern and eastern parts. In an ideal condition, climate sensitivity studies of ELA in Qilian Mountains show that if the summer mean temperature increases (decreases) by 1 \u00b0C, then ELA will increase (decrease) by about 102 m. If the annual total solid precipitation increases (decreases) by 10%, then the glacier ELA will decrease (rise) by about 6 m. The summer mean temperature is the main factor affecting the temporal trend of SLA, whereas both summer mean temperature and annual total precipitation influence the spatial change of SLA.<\/jats:p>","DOI":"10.3390\/rs13234935","type":"journal-article","created":{"date-parts":[[2021,12,6]],"date-time":"2021-12-06T03:10:38Z","timestamp":1638760238000},"page":"4935","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":20,"title":["Recent Spatiotemporal Trends in Glacier Snowline Altitude at the End of the Melt Season in the Qilian Mountains, China"],"prefix":"10.3390","volume":"13","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-2224-7907","authenticated-orcid":false,"given":"Zhongming","family":"Guo","sequence":"first","affiliation":[{"name":"Shaanxi Key Laboratory of Earth Surface System and Environmental Carrying Capacity, Xi\u2019an 710127, China"},{"name":"Institute of Earth Surface System and Hazards, College of Urban and Environmental Sciences, Northwest University, Xi\u2019an 710127, China"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-3612-1141","authenticated-orcid":false,"given":"Ninglian","family":"Wang","sequence":"additional","affiliation":[{"name":"Shaanxi Key Laboratory of Earth Surface System and Environmental Carrying Capacity, Xi\u2019an 710127, China"},{"name":"Institute of Earth Surface System and Hazards, College of Urban and Environmental Sciences, Northwest University, Xi\u2019an 710127, China"}]},{"given":"Baoshou","family":"Shen","sequence":"additional","affiliation":[{"name":"Shaanxi Key Laboratory of Earth Surface System and Environmental Carrying Capacity, Xi\u2019an 710127, China"},{"name":"Institute of Earth Surface System and Hazards, College of Urban and Environmental Sciences, Northwest University, Xi\u2019an 710127, China"}]},{"given":"Zhujun","family":"Gu","sequence":"additional","affiliation":[{"name":"Pearl River Water Resources Research Institute, Pearl River Water Resources Commission, Guangzhou 510611, China"}]},{"given":"Yuwei","family":"Wu","sequence":"additional","affiliation":[{"name":"Shaanxi Key Laboratory of Earth Surface System and Environmental Carrying Capacity, Xi\u2019an 710127, China"},{"name":"Institute of Earth Surface System and Hazards, College of Urban and Environmental Sciences, Northwest University, Xi\u2019an 710127, China"}]},{"given":"Anan","family":"Chen","sequence":"additional","affiliation":[{"name":"Shaanxi Key Laboratory of Earth Surface System and Environmental Carrying Capacity, Xi\u2019an 710127, China"},{"name":"Institute of Earth Surface System and Hazards, College of Urban and Environmental Sciences, Northwest University, Xi\u2019an 710127, China"}]}],"member":"1968","published-online":{"date-parts":[[2021,12,4]]},"reference":[{"key":"ref_1","first-page":"193","article-title":"Impact of climate change on the alpine streamflow during the past 40 a in the middle part of the QiIian Mountains, Northwestern China","volume":"22","author":"Ding","year":"2000","journal-title":"J. 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