Integrated Web-Based Access to and use of Satellite Remote Sensing Data for Improved Decision Making in Hydrologic Applications

Using NASA satellite remote sensing data from multiple sources for hydrologic applications can be a daunting task and requires a detailed understanding of the data's internal structure and physical implementation. Gaining this understanding and applying it to data reduction is a time-consuming task that must be undertaken before the core investigation can begin. In order to facilitate such investigations, the NASA Goddard Earth Sciences Data and Information Services Center (GES DISC) has developed the GES-DISC Interactive Online Visualization ANd aNalysis Infrastructure or "Giovanni," which supports a family of Web interfaces (instances) that allow users to perform interactive visualization and analysis online without downloading any data. Two such Giovanni instances are particularly relevant to hydrologic applications: the Tropical Rainfall Measuring Mission (TRMM) Online Visualization and Analysis System (TOVAS) and the Agricultural Online Visualization and Analysis System (AOVAS), both highly popular and widely used for a variety of applications, including those related to several NASA Applications of National Priority, such as Agricultural Efficiency, Disaster Management, Ecological Forecasting, Homeland Security, and Public Health. Dynamic, context- sensitive Web services provided by TOVAS and AOVAS enable users to seamlessly access NASA data from within, and deeply integrate the data into, their local client environments. One example is between TOVAS and Florida International University's TerraFly, a Web-enabled system that serves a broad segment of the research and applications community, by facilitating access to various textual, remotely sensed, and vector data. Another example is between AOVAS and the U.S. Department of Agriculture Foreign Agricultural Service (USDA FAS)'s Crop Explorer, the primary decision support tool used by FAS to monitor the production, supply, and demand of agricultural commodities worldwide. AOVAS is also part of GES DISC's Agricultural Information System (AIS), which can operationally provide satellite remote sensing data products (e.g., near- real-time rainfall) and analysis services to agricultural users. AIS enables the remote, interoperable access to distributed data, by using the GrADS-Data Server (GDS) and the Open Geospatial Consortium (OGC)- compliant MapServer. The latter allows the access of AIS data from any OGC-compliant client, such as the Earth-Sun System Gateway (ESG) or Google Earth. The Giovanni system is evolving towards a Service- Oriented Architecture and is highly customizable (e.g., adding new products or services), thus availing the hydrologic applications user community of Giovanni's simple-to-use and powerful capabilities to improve decision-making.