Development of GPS as a Volcanic Plume Sensor

1360810这笔赠款支持开发代码，希望能够使用安装在世界各地靠近活跃火山系统的地点(如冰岛的阿留申群岛)的现有全球导航卫星系统(GNSS)接收器，对喷发的火山灰和气体进行可靠、自动和远程探测。安装在世界各地的大多数现有的连续运行的GNSS接收器用于检测和量化由构造、地震、火山、地表载荷或地下流体动力学--地球被迫变形--引起的微妙(Mm)或不那么微妙(M)的位置变化？面包皮。在对已知有喷发火山灰云活动记录的火山附近站点的全球导航卫星系统信噪比观测的初步分析中，PI证明了探测烟羽的技术的可行性。该项目将进一步开发和测试使用全球定位系统信号强度数据自动探测火山羽流的算法，并将依靠多年来从数百个地点获取的全球导航卫星系统数据来确定反演的精度。这些地点将包括来自不同制造商的具有美国GPS和俄罗斯GLONASS功能的卫星接收器。这一结果将通过对阿拉斯加和冰岛火山羽流的扫描雷达观测来验证。不同接收器的性能将被编目，以向寻求实施GPS烟羽传感网络的火山科学家提供反馈。除了开发全球导航卫星系统探测火山灰羽流的代码外，该项目还将涉及全球定位系统数据的正演模拟，试图将GPS信号强度观测与火山灰浓度和颗粒大小联系起来。鉴于全球有多个全球导航卫星系统网络在许多活跃的火山系统附近运行，对保护生命和财产有影响，并对减轻航空公司的危害特别感兴趣，因此在工具包中加入了另一种以边际成本探测危险火山灰羽流的观测模式。

1360810LarsonThis grant supports development of code that hopes to allow for reliable, automated, remote detection of plumes of erupted volcanic ash and gas using extant global navigation satellite system (GNSS) receivers installed at locations around the world that are proximal to active volcanic systems (e.g., the Aleutians, Iceland). Most extant continuously operating GNSS receivers that have been installed around the world are used for detection and quantification of subtle (mm) or not so subtle (m) position changes caused by tectonically, seismically, volcanically, surface load or subsurface fluid dynamics-forced deformation of the Earth? crust. In preliminary analyses of GNSS signal to noise ratio observations at stations proximal to volcanoes with a known record of eruptive ash cloud activity, the PI has demonstrated the feasibility of the technique for detection of plumes. This project will further develop and test algorithms to automatically detect volcanic plumes using GPS signal strength data and will rely on GNSS data taken from hundreds of sites over multiple years to establish the precision of retrievals. The sites will include U.S. GPS and Russian GLONASS capable satellite receivers from various manufacturers. The results will be validated against scanning radar observations of volcanic plumes in Alaska and Iceland. The performance of different receivers will be catalogued to provide feedback to volcano scientists seeking to implement GPS plume sensing networks. In addition to developing code for GNSS detection of volcanic ash plumes, the project will involve forward modeling of GPS data in an attempt to link GPS signal strength observations to ash concentrations and particle size.Having another observational modality in the toolkit for detection of hazardous volcanic ash plumes at marginal cost, given that multiple GNSS networks are operating around the globe with many proximal to active volcanic systems, has implications for the protection of life and property and is of particular interest to mitigating airline hazards.***