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Introduction to ORNL DAAC OGC Services

The ORNL DAAC OGC services include Web Coverage Service (WCS) and Web Map Service (WMS). They serve as the foundation of the Spatial Data Access Tool (SDAT). SDAT communicates with the ORNL DAAC WCS/WMS services for users to visualize and access geospatial data on demand.

Other than SDAT, the ORNL DAAC OGC services can also be consumed by users directly through popular GIS tools (ArcGIS, uDig, etc.) and local-developed applications.

What is behind ORNL DAAC OGC Services

Capabilities XML Documents

Characteristics of ORNL DAAC OGC Services

Limitations of ORNL DAAC OGC Services

What is behind ORNL DAAC OGC Services?

ORNL DAAC OGC services are based on MapServer v5.2.0.

Capabilities XML Documents

Any OGC service shall provide an XML document through the GetCapabilities operation to describe its service metadata, including basic service information, operations supported and their access points, geospatial content provided (for WCS/WMS/...), etc. Follow the links below to access the Capabilities XML documents of ORNL DAAC OGC services.

Characteristics of ORNL DAAC OGC Services

Web Coverge Service (WCS)
- Version: 1.0.0
- URL: http://webmap.ornl.gov/ogcbroker/wcs?
- Supported Operations: GetCapabilities, DescribeCoverage, and GetCoverage
- Supported GetCoverage Parameters:
  - service: WCS
  - request: GetCoverage
  - version: 1.0.0
  - coverage
  - format
  - bbox
  - crs: EPSG Code (e.g. EPSG: 4326)
  - width
  - height
  - resx
  - resy
  - time: ISO-8601 compatible time value (e.g. 2001-02-01T00:00:00)
  - bands: 1, 2, ...
  - interpolation
  - originator: optional and for internal use, it tells where a request is sent from (e.g. originator=SDAT means the request is sent from Spatial Data Access Tool (SDAT)
- Supported Formats: ArcInfo ASCII Grid, Erdas Imagine, GeoTIFF, netCDF, and NITF
- Supported Data Types: BYTE, INT16, and FLOAT32
- Supported Projections: WGS84, Google Projection, Albers Equal Area Conic, etc.
- Supported Interpolation Methods: Nearest Neighbor, Average, and Bilinear
Web Map Service (WMS)
- Version: 1.1.1
- URL: http://webmap.ornl.gov/ogcbroker/wms?
- Supported Operations: GetCapabilities, GetMap, and GetLegendGraphic
- Supported GetMap Parameters:
  - service: WMS
  - request: GetMap
  - version: 1.1.1
  - layers
  - format
  - bbox
  - srs: EPSG Code (e.g. EPSG: 4326)
  - width
  - height
  - time: ISO-8601 compatible time value (e.g. 2001-02-01T00:00:00)
  - bands: 1, 2, ...
  - transparent: true/false
  - exceptions: format of the response if error happens (e.g. application/vnd.ogc.se_xml, application/vnd.ogc.se_inimage)
  - sld: URL of SLD XML file
  - originator: optional and for internal use, it tells where a request is sent from (e.g. originator=SDAT means the request is sent from Spatial Data Access Tool (SDAT)
- Supported Formats: PNG, GIF, and JPEG
- Supported Projections: WGS84, Google Projection, Albers Equal Area Conic, etc.

Limitations of ORNL DAAC OGC Services

Temporal Subset: At this moment, the ORNL DAAC WCS/WMS services only support temporal subset with one time step in each request. Temporal subset with multiple time steps and time period will be supported later.
Band Subset: At this moment, the ORNL DAAC WCS/WMS services only support band subset with one band in each request. Band subset with multiple bands will be supported later.