Robust DW representation: formal requirements

1. Robust DW representation: formal requirements • Standard platform- and software-independent template • both computer and human-readable • Can materialize DW into common open or vendor-specific documents or services (e.g. geodatabases, map services, SOAP services) from both local and remote data and models • Expresses how DW integrates different types of data objects from lower levels (data layers, services, real time streams, etc., processes and models, regulatory framework): various spatio-temporal or attribute join models (integration models) • Support DW analysys for completeness (data gaps), consistency (projections, formats, temporal reference), availability of integration models • ease of integration with other emerging digital representations (digital estuary, etc.) • compatibility with CI: ontology support, SOA-reliance, XML representation of sources. • evolving and flexible: ease of update as new knowledge or data sources become available

2. Synthesis models in DW • Co-location in space: boundaries of most data layers are defined by watershed boundaries • Other types: based on functional relationships between watershed parameters (atmospheric, groundwater flows, underlying geology, as well as demographic and economic variables and processes that don’t necessarily coincide with natural boundaries). • For example: pointing to conditions upstream and downstream • DW representation must explicitly include the types of joins between different watershed elements, to make automatic instantiation and update of digital watersheds possible. DW as a system of integrated views.