摘要
利用Sentinel-2卫星遥感数据监测了2016年和2018年发生在西藏阿汝错和色东普沟的冰崩灾害,重现了两次冰崩灾害事件全过程,2022年2月还对阿汝错冰崩区进行了实地调查。结果表明:阿汝错53号冰崩是一起冰川前部断裂解体后发生的冰崩,冰崩体于2018年7月全部消融,而阿汝错50号冰崩是一起典型的冰川前部垮塌产生的冰崩,2021年6月22日仍有冰崩体面积0.58 km^(2)。2017年和2018年4次大规模冰崩—岩崩—碎屑流事件不仅对色东普沟地表地貌形态和沟口水流状况产生了重要影响,对色东普流域造成了重大灾害。西藏东西两次冰崩灾害事件是气候变暖和局地强降水作用在特定的高山冰雪地形地貌结构上发生的。其中,阿汝错冰崩事件是由气候和天气驱动的外力强迫作用在该区多温和软性基岩的冰川特性上引起的,是一起历史罕见的低角度冰川的巨大灾难性不稳定事件。气候变暖引起的冰雪消融和局地强降雨是色东普沟冰崩–岩崩灾害事件发生的主要诱发因素,且呈多发、频发、周期性特点,今后很长的时间内仍会多次发生。
Sentinel-2 is a high-resolution optical Earth observation mission within the GMES(Global Monitoring for Environment and Security)programme,which is renamed Copernicus in 2012,jointly implemented by the EC(European Commission)and ESA(European Space Agency)for global land observation with high revisit capability to provide enhanced continuity of data so far provided by SPOT and Landsat.Copernicus is the most ambitious Earth Observation programme to date.It provides accurate,timely and easily accessible information to improve the management of the environment,understand and mitigate the effects of climate change and ensure civil security.At present,Sentinel-2 is one of the most important data source for remote sensing monitoring and application research,and has been widely used in monitoring natural disasters such as floods,forest fires,landslides,volcanic eruptions,and emergency response and humanitarian crises around the globe,and there are also great potentials in detecting glacier and ice and supporting relief efforts for cryospheric disaster.In this study,the glacier and ice avalanches occurred in Arutso Lake basin in northwestern Tibet and Sedongpu basin in southeastern Tibet in 2016 and 2018 were investigated using Sentinel-2 images and field surveys,and the evolution process of two events were reproduced,which has important reference significance for monitoring cryospheric hazard,emergency relief and management in other mountain regions on the world.Study shows that Arutso No.53 glacier avalanche completely melted away in July 2018 after lasting for two years from occurrence to final disappearance,while the area of Arutso No.50 glacier avalanche is 0.58 km^(2) left on June 22,2021 because of more thickness compared to Arutso glacier No.53.Four large-scale ice-rock avalanche and debris flow events in the Sedongpu basin in 2017 and 2018 not only had significant impacts on the river flow,landscape and landform in the basin,but also caused great disasters in the basin and downstream.Two glacier and ice avalanche events were caused by climate warming and local heavy precipitation,acting on specific topographic and geomorphic structure of glacier properties in high mountains.Specifically,Arutso glacier avalanche was caused by climate-and weather-driven external forcing,acting on specific polythermal and soft-bed glacier properties and is an unprecedented large catastrophic instability of low angle mountain glaciers.Glacier and snow melting caused by climate warming and heavy rainfall are main triggering factors for ice and rock avalanche in the Sedongpu basin,which is a typical hazard cascades originating from cryosphere,followed by rock fall,debris flow,dammed lake,and lake outburst flood disaster.It often occurs in the Sedongpu basin and will continue to occur for a long time in the future,and the high mountain ridge covered with ice and snow in the right side of back of the basin is still a high-risk area for ice and rock avalanches in the future.
作者
除多
才旺顿珠
拉旺顿珠
索朗塔杰
平措桑旦
多吉扎西
明玛次仁
平措
Chu Duo;Caiwang Dunzhu;Lawang Dunzhu;Suolang Tajie;Pingcuo Sangdan;Duoji Zhaxi;Mingma Ciren;Ping Cuo(Tibet Institute of Plateau Atmospheric and Environmental Sciences,Lhasa 850000,China;Tibet Key Laboratory of Plateau Atmosphere and Environment Research,Lhasa 850000,China;Gaize Meteorologial Bureau,Gaize 859200,China;Rutog Meteorologial Bureau,Rutog 859700,China)
出处
《遥感技术与应用》
CSCD
北大核心
2022年第6期1289-1301,共13页
Remote Sensing Technology and Application
基金
第二次青藏高原综合科学考察研究项目(2019QZKK0603、2019QZKK010312),西藏自治区科技创新基地自主研究项目(XZ2021JR0001G),国家自然科学基金项目(41561017、42061014)。
作者简介
除多(1969-),男,西藏白朗县人,博士,正研级高工,主要从事卫星遥感应用研究,E-mail:chu_d22@hotmail.com。
