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As glaciers recede in response to global climate change, significant growth of glacial lakes is being witnessed in the Himalayan region. Owing to their high elevations, rapid growth, and their occurrence behind loosely consolidated glacial moraine deposits, these lakes pose a significant threat of glacial lake outburst floods (GLOFs). This study focused on tracing the glacial lake evolution in the Shyok catchment of the Upper Indus Basin over a 30-year period (1992–2022) and carrying out a GLOF hazard assessment. Multitemporal medium- and high-resolution satellite imagery was used to inventorize, detect spatiotemporal change in, and classify glacial lakes with areas more than 0.001 km2 , as well as to extract various lake characteristics. The GLOF hazard assessment was carried out using a multicriteria approach based on the analytical hierarchy process (AHP). We found significant increases in the total number, from 143 (1992) to 240 (2022), and combined area, from 8.45±0.02 km2 (1992) to 13.26±0.04 km2 (2022), of glacial lakes. Out of 63 glacial lakes with areas >0.05 km2 , four lakes were classified as very-high-hazard lakes, with GLOF susceptibility indices above 0.75, and 12 were classified as high-hazard lakes, with GLOF susceptibilities indices of 0.66–0.75. These hazardous lakes have had a high growth rate owing to increasing temperature trends in the region. Our findings also suggest that the GLOF hazard of these lakes is going to continue increasing as a result of lake expansion and enhanced exposure to landslides and avalanches. The identification of potentially dangerous glacial lakes and assessing their GLOF hazard will help prioritize future research and develop better mitigation strategies for potential future disasters in the area. [ABSTRACT FROM AUTHOR]

Climate warming has caused accelerated glacier recession in the Eastern Himalayas. This phenomenon has consequently resulted in the development of new glacial lakes and expansion of the existing ones. The outbursts of these lakes has the potential to cause flashfloods with negative impacts for the downstream community. This study used Remote Sensing data products to develop a glacial lake database of Dibang River Basin for the year 2020. The multi-temporal Landsat series data was used to examine the surficial changes in glacial lakes larger than 0.1 km². The key parameters derived from previous glacial lake studies were used to identify the Potentially Dangerous Glacial Lakes (PDGLs) and conduct their hazard assessment. Finally, the Indian Monsoon Data Assimilation and Analysis (IMDAA) data was used to analyze the Temperature and Precipitation trends from 1980 to 2020 to understand timpact of climate change on lake behaviour. Our findings reveal that the study region has 403 glacial lakes with a total area of 55.73 km² in 2020. The area of selected glacial lakes has increased from 29.96 km² in 1985 to 32.56 km² in 2020 at a rate of 0.07 km² per year. Twelve (12) lakes were identified as PDGLs in the study region. After applying the weighted index method, 4 lakes among them were categorized as high, 5 as medium and 3 as low hazard glacial lakes. The Mann Kendal test of Tmin, Tmax and Tmean revealed an increasing trend with a Z statics value of >0, whereas mean precipitation on the contrary showed a significant decreasing trend with a Z statics value of <0. The changes in climatic variables (i.e., temperature and precipitation) indicate that the warmer conditions prevail in the region, causing glacier shrinking and retreat, formation of new lakes and expansion of existing ones. Hence, we propose the continuous monitoring and assessment of high hazard glacial lakes for the prevention and mitigation of Glacier Lake Outburst Floods (GLOFs) in the study region. [ABSTRACT FROM AUTHOR]

In the Himalayan Mountain region, a large number of glacial lakes have developed in the recent past due to glacier recession under the influence of climate change. In this study, we used high resolution satellite data such as Indian Remote Sensing (IRS) LISS-IV (5.8 m) and Google earth images supplemented with field survey to generate an updated glacial lake inventory of Upper Jhelum Basin (UJB) of Kashmir Himalaya. The Sentinel-2A (10 m), Landsat-OLI (30 m) and MSS (60 m), and Cartosat-DEM (30 m) were additional data sources used for glacial lake mapping and change detection analysis. A total of 393 glacial lakes covering an area of 21.55 ± 3.8km² were identified, mapped and inventoried. The lake inventory includes 102 proglacial lakes, 13 supraglacial lakes and 278 unconnected glacial lakes. Using the weighted index-based method, 21 glacial lakes were found as Potentially Dangerous Glacial Lakes (PDGLs). Out of these, 7 lakes were classified as High, 9 as Medium and 5 as Low hazard glacial lakes as per the hazard assessment. Change detection analysis of PDGLs from 1980 to 2020 revealed an increase in area from 5.92 km² to 8.46 km² thereby, indicating a growth of 2.51 ±0.9 km² (30%) at a rate of 0.063 km²/year. The formation and growth of glacial lakes in this area is attributed to continuous glacier recession under the warming trend of temperature and declining nature of precipitation. In this study, the findings showed that Tavg and Tmin are rising significantly at a rate of 0.004°C/year and 0.013°C/year respectively. This study provides an important database for future GLOF studies in the region. [ABSTRACT FROM AUTHOR]