HR: 15:25h
AN: IN53C-08    [Abstracts]
TI: Design and implementation of CUAHSI WaterML and WaterOneFlow Web Services
AU: * Valentine, D W
EM: valentin@sdsc.edu
AF: San Diego Supercomputer Center, 9500 Gliman Dr #0505 University of California, San Diego, La Jolla, CA 92037, United States
AU: Zaslavsky, I
EM: zaslavsk@sdsc.edu
AF: San Diego Supercomputer Center, 9500 Gliman Dr #0505 University of California, San Diego, La Jolla, CA 92037, United States
AU: Whitenack, T
EM: twhitenack@sdsc.edu
AF: San Diego Supercomputer Center, 9500 Gliman Dr #0505 University of California, San Diego, La Jolla, CA 92037, United States
AU: Maidment, D
EM: maidment@mail.utexas.edu
AF: Center for Research in Water Resources, Bldg 119, MC R8000 University of Texas at Austin, Austin, TX 78712, United States
AB: WaterOneFlow is a term for a group of web services created by and for the Consortium of Universities for the Advancement of Hydrologic Science, Inc. (CUAHSI) community. CUAHSI web services facilitate the retrieval of hydrologic observations information from online data sources using the SOAP protocol. CUAHSI Water Markup Language (below referred to as WaterML) is an XML schema defining the format of messages returned by the WaterOneFlow web services. \newline WaterML CONCEPTS \newline The goal of the first version of WaterML was to encode the semantics of hydrologic observations discovery and retrieval and implement WaterOneFlow services in a way that creates the least barriers for adoption by the hydrologic research community. In particular, this implied maintaining a single common representation for the key constructs returned on web service calls, related to observations, features of interest, observation procedures, observation series, etc. In addition to point measurements described in the CUAHSI Observations Database Model (ODM) specification, hydrologic information may be available as observations or model outcomes aggregated over user-defined regions or grid cells. While USGS NWIS and EPA STORET exemplify the former case, sources such as MODIS and Daymet are examples of the latter. In this latter case, as in the case of other remote sensing products or model-generated grids, the observation or model-generated data are treated as fields, and sources of such data are referenced in WaterML as datasets, as opposed to sites. \newline IMPLEMENTATION \newline WaterML is primarily designed for relaying fundamental hydrologic time series data and metadata between clients and servers, and to be generic across different data providers. Different implementations of WaterOneFlow services may add supplemental information to the content of messages. However, regardless of whether or not a given WaterML document includes supplemental information, the client shall be sure that the portion of WaterML pertaining to space, time, and variables will be consistent across any data source. Depending on the type of information that the client requested, a WaterOneFlow web service will assemble the appropriate XML elements into a WaterML response, and deliver that to the client. The core WaterOneFlow methods include: \newline * GetSiteInfo – for requesting information about an observations site, and returns site properties, and observation series for that site. \newline * GetVariableInfo – for requesting information about a variable, and returns variable properties. \newline * GetValues – for requesting a time series for a variable at a given site or spatial fragment of a dataset, and returns data values, and associated variable and site properties to make a single self-contained request. \newline The CUAHSI WaterML description has been submitted as a discussion paper to the Open Geospatial Consortium, and is available from the OGC portal. The project web site is http://www.cuahsi.org/his .
UR: http://www.cuahsi.org/his
DE: 1819 Geographic Information Systems (GIS)
DE: 6339 System design
DE: 9810 New fields (not classifiable under other headings)
SC: Earth and Space Science Informatics [IN]
MN: 2007 Fall Meeting