Synergistic analysis of satellite, unmanned aerial vehicle, terrestrial laser scanner data and process-based modelling for understanding the dynamics and morphological changes around the snout of Gangotri Glacier, India

被引：12

作者：

Dhote, Pankaj R. ^{[1
]}

Thakur, Praveen K. ^{[1
]}

Chouksey, Arpit ^{[1
]}

Srivastav, S. K. ^{[1
]}

Raghvendra, S. ^{[1
]}

Rautela, Piyoosh ^{[2
]}

Ranjan, Rajeev ^{[1
]}

Allen, Simon ^{[3
]}

Stoffel, Markus ^{[3
,4
,5
]}

Bisht, Sanjay ^{[1
]}

Negi, Bhupender Singh ^{[6
]}

Aggarwal, S. P. ^{[1
]}

Chauhan, Prakash ^{[1
]}

机构：

[1] ISRO, Indian Inst Remote Sensing, Dehra Dun, Uttarakhand, India

[2] Disaster Mitigat & Management Ctr, Dehra Dun, Uttarakhand, India

[3] Univ Geneva, Inst Environm Sci, CH-1205 Geneva, Switzerland

[4] Univ Geneva, Dept Earth Sci, CH-1205 Geneva, Switzerland

[5] Univ Geneva, Dept FA Forel Environm & Aquat Sci, CH-1205 Geneva, Switzerland

[6] Geol Survey India, Uttarakhand State Unit, Dehra Dun, Uttarakhand, India

来源：

GEOMORPHOLOGY | 2022年 / 396卷

关键词：

Gangotri Glacier; Debris flow; Remote sensing; Unmanned aerial vehicles (UAVs); Terrestrial laser scanning (TLS); Rapid mass movement simulation (RAMMS); DIGITAL ELEVATION MODELS; LAKE OUTBURST FLOOD; GARHWAL HIMALAYA; CLIMATE-CHANGE; MASS-BALANCE; DEBRIS FLOWS; RETREAT; RECESSION; LANDSLIDES; ACCURACY;

D O I：

10.1016/j.geomorph.2021.108005

中图分类号：

P9 [自然地理学];

学科分类号：

0705 ; 070501 ;

摘要：

The glaciated areas of the Himalaya often experience mass movement, glacial lake outburst flood and other associated hazards, posing threat to the communities and infrastructure in the downstream areas. A large debris flow occurred during July 16-19, 2017 near the present snout of the Gangotri Glacier in the Garhwal Himalaya, India resulting in significant geomorphological changes in the vicinity. The present study assesses the applicability of multi-source remote sensing data from satellites, unmanned aerial vehicle (UAV) and terrestrial laser scanner (TLS) along with process-based modelling to understand and quantify glacier snout dynamics and morphological changes around Gangotri Glacier in the Garhwal Himalaya of India. We show that retreat rates of Gangotri Glacier snout along the lateral flowlines are (left flowline 29.6 m year(-1); right flowline 60.5 m year(-1)) are significantly higher compared to the central flowline (18.2 m year(-1)) during 2010-2020 leading to total loss in glacial ice area of 0.11 +/- 0.015 km(2). The snout dynamics and evolution of the new channel from the terminus of the adjoining Meru Glacier, connecting the moraine-dammed glacial lake and the Bhagirathi River, suggest that retreat of the Gangotri Glacier, intense precipitation and excessive seepage from the glacial lake were the important drivers of the debris flow in July 2017. The accumulated debris occupied an area of similar to 0.25 km(2) near the snout of the Gangotri Glacier and shifted Bhagirathi River by 36-200 +/- 9.35 m towards northeast. The synergistic analysis of pre-and post-event satellite, UAV and TLS-based digital elevation models (DEMs) and satellite images indicate that about similar to 8 +/- 0.066 x 10(6) m(3) of sediments were generated by the debris flow. The results from remote sensing data suggest that a significant portion (similar to 60%) of the deposited debris has been transported to the downstream areas between July 16-19, 2017 and October 2, 2017. Regular monitoring of the area is recommended, especially in light of climate change using earth observation data and ground measurements. The multi-source integrated framework implemented in this study is generic and can be applied for any debris flow or landslide studies in glaciated terrain. (C) 2021 Elsevier B.V. All rights reserved.

引用

页数：15