PBO H2O: Using EarthScope GPS Data to Generate Water Cycle Products

地球镜板块边界观测站（PBO）是美国最大的用于科学研究的GPS网络。它的特点是高质量的仪器，一个开放的数据政策，以及易于获得的定位产品的地壳变形研究。最近的研究表明，许多PBO站点也提供了有关每个GPS天线周围陆地表面状况的宝贵信息。来自这些GPS站点的数据被用于监测三个关键水文变量的波动：土壤湿度、雪深/雪水当量和生物量。来自GPS站点的水循环产品是独一无二的，因为该方法对每个PBO天线周围10,000平方米的区域很敏感。这填补了典型的现场传感器（100平方厘米）和卫星测量（100平方公里）之间的关键差距。这些数据对于气候研究、水资源管理和天气预报具有重要意义，从而在改善农业生产的同时改善并可能减轻洪水和干旱等自然灾害。这些研究领域的进步直接关系到美国的经济和公共安全。全球定位系统水循环产品和误差评估每天都在生成，并向公众提供。为加强科学分析，每个PBO站点都提供了辅助气象数据（温度、降水）和其他遥感环境数据集。这项研究是跨学科的，加强了全球定位系统与传统水循环科学界之间的联系。根据这项研究开发的所有产品均可通过联安援助团向公众提供（http://pbo.unavco.org）。在线数据工具允许公众访问和可视化水循环产品。为这个项目开发的技术和标准正在广泛提供，从而将水循环研究扩大到美国和国外的其他GPS网络。

The EarthScope Plate Boundary Observatory (PBO) is the largest GPS network for scientific studies in the United States. Its hallmarks are high-quality instrumentation, an open data policy, and easily accessible positioning products for crustal deformation studies. Recently it has been shown that many PBO sites also provide valuable information about land surface conditions surrounding each GPS antenna. Data from these GPS sites are being used to monitor fluctuations in three critical hydrologic variables: soil moisture, snow depth/snow water equivalent, and biomass. Water cycle products derived from GPS sites are unique because the method is sensitive to the 10,000 m2 area around each PBO antenna. This fills a critical gap between typical in situ sensors (100 cm2) and satellite measurements (100 km2). These data are important for climate studies, water management, and weather forecasting, thus improving, and possibly mitigating, natural hazards such as floods and droughts while improving agricultural production. Improvements in these research areas are directly linked to the U.S. economy and public safety. GPS water cycle products and error assessments are being generated on a daily basis and made available to the public. Ancillary meteorological data (temperature, precipitation) and other remotely sensed environmental datasets are provided for each PBO site in order to enhance scientific analysis. This research is interdisciplinary and strengthens connections between the GPS and traditional water cycle scientific communities. All products developed from this research are available to the public through UNAVCO (http://pbo.unavco.org). Online data tools allow the public to both access and visualize the water cycle products. The techniques and standards developed for this project are being made broadly available, thus expanding water cycle studies to other GPS networks in the United States and abroad.