Estimating the Changes in Glaciers and Glacial Lakes in the Xixabangma Massif, Central Himalayas, between 1974 and 2018 from Multisource Remote Sensing Data

Abstract

The continuous melting of valley glaciers can impact the water levels of glacial lakes and create glacial lake outburst floods (GLOFs). The Xixabangma massif is one of the most populated areas in the Himalayas and has suffered from multiple GLOFs. To estimate the glacier melting rate in the past four decades and analyze the outburst risk of glacial lakes in the Xixabangma massif, we determined changes in glacier mass balance, glacier area and glacial lake area based on KH-9 images, TanDEM-X images, Landsat images, SRTM DEM and ICESat-2 elevations. Our results show that, from 1974 to 2018, the total glacier area shrank from 954.01 km2 to 752.46 km2, whereas the total glacial lake area grew from 20.90 km2 to 38.71 km2. From 1974 to 2000, 2000 to 2013 and 2013 to 2018, the region-wide glacier mass balance values were −0.16 m w.e./a, −0.31 m w.e./a and −0.29 m w.e./a, respectively. Three glacial lakes, named Gangxico, Galongco and Jialongco, respectively, expanded by 127.14%, 373.45% and 436.36% from 1974 to 2018, and the mass loss rates of their parent glaciers from 2000 to 2013 increased by 81.72%, 122.22% and 160.00% relative to those during 1974 to 2000. The dams of these three lakes are unstable, and their drainage valleys directly connect to a major town and its infrastructure. Due to current high-water levels, possible external events such as ice collapse, landslide, heavy rainfall and earthquakes can easily trigger GLOFs. Hence, we deemed that the Gangxico, Galongco and Jialongco glacial lakes are dangerous and require special attention.

Glacial Lake Outburst Flood Hazard and Risk Assessment of Gangabal Lake in the Upper Jhelum Basin of Kashmir Himalaya Using Geospatial Technology and Hydrodynamic Modeling

“…Glacial lakes are susceptible to breach outbursts under the conditions of rapid warming and incessant rainfall (extreme weather events). GLOFs may also occur due to the sudden ice/rock avalanche, landslides, cloud bursts, glacier surges, ice core melting, and glacier snout calving [33]. The temperatures in the entire Indian Himalayan region are significantly increasing, as evident from recent studies [45,162,163].…”

“…As illustrated in Figure 10, a significant variation in velocity and flow was observed across the glacier (accumulation zone, ablation zone, terminus). Several studies have carried the glacier surface velocity using satellite images at the catchment level [33,93,94,146] and on individual glaciers across the Himalayan region [147][148][149]. Garg et al [150] have studied the glacier surface velocity of the Sakchum, Chota Shigri, and Bara Shigri glaciers, revealing an average velocity of 10.2, 20.9, and 25.3 m/yr, respectively, using ASTER images.…”

“…Earlier, glacial lake studies in the former state of Jammu and Kashmir were carried out at different levels, for example, at the international level (glacial lake inventory of HMA) by Ives et al [32], Wang et al [33], and Chen et al [34]; at the national level by the Central Water Commission [35], National Remote Sensing Center Hyderabad [36], Ives et al [32], Fujita et al [37], and Worni et al [38]; and at the basin level by Dar et al [39] and Ahmed et al [40,41]. The Potentially Dangerous Glacial Lakes (PDGLs) in the area have been identified by seven previous studies.…”

Multitemporal Glacier Mass Balance and Area Changes in the Puruogangri Ice Field during 1975–2021 Based on Multisource Satellite Observations

“…The glacier boundaries within the Puruogangri Ice Field were extracted using the semi-automated band ratio method (Red/SWIR) [18] with band 3 and band 5 of the Landsat TM and ETM+ images from 2000 and 2012 and with band 4 and band 6 of the Landsat OLI images from 2015, 2017 and 2021. The first step was radiation correction, which included radiation calibration and atmospheric correction [10]. Then, the band ratio method was employed using a threshold of 2.0 to distinguish glaciers from non-glacial terrain.…”

“…Global glaciers (including ice sheets) cover an area of 14.51 × 10 6 km 2 and the volume of total ice reserves is about 27.6 × 10 6 km 3 , which stores 75% of global freshwater resources [4]. The Tibetan Plateau (TP) is the largest modern glacier area in the middle and lower latitudes of the world and the glaciers on most parts of the TP have generally been undergoing an accelerated retreat due to climate warming [3][4][5], which has had a great impact on water resources [6], sea-level rise [7] and increased glacial hazards, such as glacier collapse [8,9] and glacial lake outburst floods [10,11]. By studying the changes in mountain glaciers on the TP, it is not only possible to understand the characteristics and trends of glacier changes in this region but also to further investigate the relationships between glacier changes and climate change, regional water availability and disaster occurrence, which is of great importance [12][13][14].…”