预测雷达数据的冰雪崩

Author:Lorenz Meier

The risk of natural hazards and the associated damage are globally on the rise. Extensive protection structures are costly and may not prevent damage by themselves. Spatial planning and preventative measures have become the most important actions for successful civil and assets protection. Permanent monitoring of the specific hazard processes allows for early detection of an imminent risk or the continuous modification of the hazard situation. The potential damage caused by an event can be remarkably reduced with warning and alarm systems – if set up and used correctly.

基于瑞士的技术公司Geopraevent是该领域的专家。GeopraEvent开发，安装和操作定制的报警和监控系统，以获得各种自然灾害，如雪崩（雪和冰），岩石秋季，碎片流量或洪水。所应用的技术包括不同类型的雷达，例如，基于意大利的地面穿透雷达和干涉技术解决方案IDS Georadar提供的基于意大利的领先提供商提供的干涉雷达。GeopraEvent目前在全球范围内运行60多种系统，其中许多在高山环境中。最近，其中一个清楚地证明了这种能力predict an imminent event and react early: the failure of the Trift Glacier on Weissmies situated above the village of Saas Grund in Switzerland’s region of Wallis。

在高山环境中挑战监测任务

Fletschhorn（3993米），Lagginhorn（4010米）和Weissmies（4017米）的众所周知的峰会（4017米）将SaaS-Valley分开，瑞士南部的Simplon Valley分开。距离位于Hohsaas的缆车站方便易于到沃尔斯州，Weissmies是该地区最常见的山峰之一。

In summer 2014, the Trift Glacier, located on the north-west face of Weissmies, showed increased ice avalanche activity. The hanging glacier, formerly supported by ice from below, had destabilised due to glacier mass loss predominating in steeper areas. Canton of Wallis authorities approached Geopraevent with the request to monitor the glacier movement to enable early actions in case of possible ice failures resulting in a large ice/snow avalanche. The specialised engineers of Geopraevent visited the measurement site immediately and supplied the local decision makers and responsible authorities withglacier velocity dataon the evening of the day of installation.

集成到岩土性分析中的干涉雷达数据提供了判断局势的专家所需的详细信息。干涉测量雷达是无论可见性和天气条件如何，用于短期或长期监测多种位移尺度的可靠技术。雷达测量高精度的空间解决的变形速率。IDS GeoRadar IBIS FM radar是系统提供的尽管高海拔地区需要大气校正，但实时可靠和准确的位移数据。此外，如果天气不是问题，那么在这个位置安装了一台高清摄像头，并被证明是自动长期变形分析的优异替代方案。

Critical landslide and ice avalanche monitoring for safety

Despite the turbulent atmosphere over the glacier that can hamper the measurements at times, reliable measurements have so far been obtained daily. To account for the highly variable alpine conditions, Geopraevent added an extra processing step that verified the plausibility of the data before making it available to the customer via its在线数据门户网站。This provided sufficient data for VAW/ETH Professor’s Martin Funk group and the local geoformer GmbH’s engineers to解释现行危险for the area below the hanging glacier.

“经过近三年的连续雷达监测，统计数据显示，雷达在95％的日子里发出可行变形数据。由于雪雨引起的表面变化，雷达测量仅在大雪风暴期间暂时失败，“said Richard Steinacher, physicist and project leader at Geopraevent.

Compared to the rest of the glacier moving at about 10 centimetres per day, the unstable part initially moved at a significantly higher velocity of approximately 25 cm per day. Between 2014 and 2017, dozens of small and harmless ice avalanches could be predicted from the radar data usually a few days in advance.

通过预测不可避免地拯救生命

After 2.5 years of successful operation, the interferometric radar was replaced by a high-resolution camera in early 2017 for visual deformation analysis. This camera delivered excellent results that tracked the movements of the glacier daily if visibility conditions permitted. The camera analysis revealed a distinct acceleration of the glacier starting around August 20^th。In the beginning of September, it was clear that the glacier would fail soon.

To provide velocity data also during night and bad weather, Geopraevent re-installed the interferometric radar on September 7^th。Velocities were on the order of 80 cm per day and accelerated to more than 2 m per day on Saturday, September 9^th。对那一天的突破预测建议冰量高达400,000米³将在9月10日星期日的清晨失败^th。Consequently, 220 inhabitants of the濒临灭绝的村庄的萨斯格翁群落被疏散。Most of the unstableice volume collapsed, as predicted，周日，周日，6 A.M ..幸运的是，雷达干涉图透露的十分钟内拆除了几个小部分。没有发生伤害，凌晨8点。所有居民都可以回到家里。

Real time safety monitoring and long-term planning

IDS GeoRadar IBIS-FM system collects quantitative information on slope behaviour from either a spatial or a temporal point of view. It provides reliable early-detection alerts on impending failures in real time, as well as accurate geo-referenced outputs over long periods of time allowing users tointegrate radar data into geotechnical analysis of slope failure mechanisms。

“The IBIS-FM radar accurately monitors multiple scales of displacements in real time, from early detection of slow movements to fast accelerations associated with slope collapse. The great operative range, up to 4500 metres allows to safely deploy the system in comfortably accessible areas without exposing people and equipment to hazardous zones,”said Paolo Papeschi, IDS GeoRadar GEO business unit manager.“由于市场上最先进的自动算法，IBIS-FM在所有天气条件下提供可靠和准确的数据。监控专家可以更快地响应坡危险，确保运营商和公众的安全性。“

Geopraevent还在瑞士格劳布登州州格雷德尔州哥斯兰登·斯格尔登（Bergeld）的地区上方安装了一个IDS Georadar系统，在2017年8月发生了巨大的滑坡之后。2017年9月3日安装的雷达，永久监测Pizzo Cengalo和Pizzo Cengalo在所有天气条件下检测毫米运动。The radar allows to predict new rockfalls early and initiate appropriate measures; a rock fall event on 15 September 2017 was predicted about one day in advance.