CSIR-Central Scientific Instrument Organisation, Chandigarh 160030, India; Academy of Scientific and Innovative Research (AcSIR-CSIO), CSIR-CSIO campus, Chandigarh 160030, India.
National Centre for Sustainable Coastal Management, Chennai 600025, India; Sathyabama Institute of Science and Technology, Chennai 600119, India.
Sci Total Environ. 2020 Apr 20;714:136455. doi: 10.1016/j.scitotenv.2019.136455. Epub 2020 Jan 7.
The presented study reports applicability of Lake Detection Algorithm (LDA) for an automated extraction of glacial lakes over a large geographical region and dynamics of Samudra Tapu and Gepang Gath glacial lakes. The areal extent of lake boundary extracted through LDA and areal extent of manually interpreted lake boundary exhibit a remarkable agreement (R~0.99). Glacial lake dynamics is assessed in terms of areal and volumetric expansion for two selected glacial lakes from 1979 to 2017, i.e. Samudra Tapu (0.95 km), and Gepang Gath (0.67 km). They show volumetric expansion from 8.52 × 10 m (1979) to 80.34 × 10 m (2017) and 2.04 × 10 m (1979) to 32.44 × 10 m (2017) respectively. Statistical analysis (Mann-Kendall and Sen's slope) of climate data indicates rise in mean annual temperature (0.021 °C yr; 1961-2015) and fall in annual precipitation (-2.74 mm yr; 1951-2015) at different confidence intervals. Further Glacial Lake Outburst Flood (GLOF) is modelled using empirical relationship and Simplified Dam Breach Model (SMPDBK). The SMPDBK demonstrates discharge of 3866.52 and 2100.90 m s reaching Chhatru and Sissu village posing threat to life and property. The study also exhibits that glacial shrinkage under the influence of climate change causes expansion of glacial lakes. This expansion is expected to intensify catastrophic GLOF and resultant fatalities and destruction in the downstream region.
本研究报告了湖泊检测算法（LDA）在自动提取大面积地理区域内的冰川湖以及萨姆德拉塔普和格潘加特冰川湖的动态方面的适用性。通过 LDA 提取的湖边界面积与手动解释的湖边界面积之间存在显著的一致性（R~0.99）。通过从 1979 年到 2017 年对两个选定的冰川湖（萨姆德拉塔普（0.95 公里）和格潘加特（0.67 公里））的面积和体积扩张来评估冰川湖的动态。它们的体积从 1979 年的 8.52×10m 扩展到 2017 年的 80.34×10m 和从 2.04×10m 扩展到 2017 年的 32.44×10m。对气候数据的统计分析（Mann-Kendall 和 Sen 斜率）表明，在不同置信区间内，年平均气温（0.021°C yr；1961-2015 年）上升了 0.021°C yr，年降水量（1951-2015 年）下降了 2.74 mm yr。进一步使用经验关系和简化大坝溃决模型（SMPDBK）模拟冰川湖突发洪水（GLOF）。SMPDBK 演示了 3866.52 和 2100.90 m s 的流量，到达 Chhatru 和 Sissu 村庄，对生命和财产构成威胁。该研究还表明，气候变化的影响下冰川的收缩导致冰川湖的扩张。这种扩张预计会加剧灾难性的 GLOF 及其在下游地区造成的人员伤亡和破坏。
