雪崩的监测研究综述

A review of study on snow avalanches monitoring

雪崩是藏东南地区非常严重的一种自然灾害,准确且及时地监测并获得雪崩活动信息在雪崩灾害的减灾防灾中发挥着最为重要的作用。雪崩活动的监测包括实地监测和遥感监测两种基本类型,其中实地监测可以采取雪体试验、定点长期监测和次声地震波三种方法,不同方法相互印证会取得更好的监测效果。近年来随着摄影测量及航空航天科技的发展,遥感监测在雪崩的灾害管理、预测预警以及工程防治中的作用也愈加重要。与实地观测和定点监测相比,雪崩的遥感监测不直接接触不稳定性积雪,所以安全性更高。雪崩的遥感监测采用光学、激光和雷达三种传感器,搭载在地面、航空或者卫星平台之上,可以对不同空间尺度的雪崩进行临时或连续性观测。不同的传感器及平台都有各自的优势和局限性,在实际的雪崩监测中需根据成本、可到达性以及观测目标等因素灵活应用。大范围雪崩的自动监测及其算法问题依然是雪崩遥感监测的难点。藏东南是湿雪雪崩的高发地区,可以采用实地观测和高分辨率的RS-2U雷达影像相结合的方法进行长期监测,并采用哨兵-1号、SPOT或QuickBird光学影像进行验证。波密嘎隆拉隧道附近是藏东南雪崩的高发区,又是连接波密县和墨脱县的主要公路,适合建设固定的雪崩观测站进行长期观测。

Snow avalanches are frequent and destructive mountain hazards in snow-covered mountains.Accu⁃rate and timely information on avalanche occurrence is a key factor for avalanche warning,crisis management and avalanche documentation.There are two monitering means on snow avalanche:field-based approaches and remote sensing.Of the field-based approaches,three methods can be taking:snow test,long-term site observa⁃tion,as well as seismic and infrasound detections.However,field-based approaches fail in creating continuous datasets on avalanche activity on inaccessible regions.The use of remote sensing instruments in avalanche sci⁃ence has large potential to help fill these data gaps.In this paper,we review past and current avalanche detection using ground based,air-,and space borne remote sensing data from optical,laser,and radar sensors,and ana⁃lyze their advantages and disadvantages.Being a young and evolving scientific field,automatic detection and al⁃gorithm,remote sensing of large spatial avalanches is still a challenge the researchers have to be faced.Which platform-sensor combination should be deployed depends largely on the spatio-temporal scale of the monitoring purpose.Both optical time-lapse cameras and terrestrial LiDAR scanners are recommend deploying for continu⁃ous slope-scale monitoring.For regional-scale monitoring of avalanche activity,optical-and radar satellite data are the preferred technology.The Southeastern of Qinghai-Xizang(Tibet)Plateau,with a wet snow avalanche region and abundant snowfall in spring,it is recommend that radar satellites,such as RS-2U or Sentinel-1 to monitor the avalanche in this region,and validated by Very High Resolution(VHR)optical remote sensing im⁃agery like SPOT6/7 or QuickBird under clear conditions.The Doxiongla Tunnel is an ideal site to monitering av⁃alanche on field base.