Web service based architecture for US national crop progress monitoring system

Crop development progress information is critical to decision makings in National Agriculture Statistics Services (NASS) of United State Department of Agriculture (USDA), other federal agencies, and public users. NASS currently compiles and issues the weekly national crop progress report based on crop conditions reported by state and county agricultural officials. The report is point-wise sampled, subjectively estimated by field enumerators and lacks spatially distribution information. The applications of remote sensing technologies have been limited to a low-resolution static image posted on the web weekly during the growing season, without enough quantitative information for NASS customers to fully support their decision makings. This study designs a service-oriented architecture by leveraging open geospatial standards and specifications, especially those on Sensor Web technology. The new monitoring system aims at overcoming the shortcomings of existing crop progress systems/procedures by utilizing NASA satellite-based vegetation index, leaf area index, land surface temperature, precipitation, and soil moisture, and model-based longterm weather forecast and by integrating these products with USDA's crop area and other data. Advanced workflow for composing Web services was used in automatically producing and disseminating an objective and quantitative national crop progress map and associated decision support data at high-spatial resolution, as well as summary reports. Standard-compliance enables the reusability and multiple-purpose of functionalities provided by individual geospatial Web services and their composed workflows.