DEVELOPING AND CHAINING WEB PROCESSING SERVICES FOR HYDROLOGICAL MODELS

Available geospatial resources on the Web need to be accessed and easily exploited by scientists and decision makers. Organizations at multiple administrative levels are establishing interoperable infrastructures to improve accessibility, such as the Global Earth Observation System of Systems (GEOSS), and the Infrastructure for Spatial Information in Europe (INSPIRE). Also regarding hydrological resources management we encounter initiatives being carried out around the globe, to merge computer science with hydrology in order to improve the way experts work and make decisions. The current trend in geospatial applications and the key unit in the mentioned initiatives are Spatial Data Infrastructures (SDI) based on access to data and processes via web services following OGC (Open Geospatial Consortium) standards. Traditional SDIs support the most common and basic requirements of geospatial data users: discovery, access, download and visualization of the data. Specialized users such as hydrological scientists, however, require more advanced services for processing data and observations using specialized models. There is a need to expose these models in SDI so scientific community can run and share them, as they do with data resources. In this framework we deployed two hydrological models where functionality is offered by a set of reusable web processing services on top of an SDI. These web services, designed with the criteria of modularity, can be reused to orchestrate distributed hydrological applications where shared remote data sources can be processed together with local data. In the framework of the GMES EC-funded project AWARE (A tool for monitoring and forecasting Available WAter REsource in mountain environments, www.aware-eu.info) we have built an application for predicting water discharge in the Alpine catchments based on a chain of these web geospatial services. The chain is provided to users within a Geoportal which is the entry point to an INSPIRE-based SDI where experts are guided to run one hydrological model.