The Thematic Real-time Environmental Distributed Data Services (THREDDS) server has features and interfaces that make it easier to explore and use data, both interactively and via automatic clients. These utilities work for most model data served at NCEI. Both Gridded Binary (GRIB) and Network Common Data Form (NetCDF) files use these services.
NetCDF markup language (NcML) aggregations and forecast model run collections (FMRC) are gridded datasets composed of multiple files joined along a dimension to form virtual continuous units. These aggregations allow extremely large collections of data to be explored and subsetted using THREDDS services, like OPeNDAP and NetCDF Subset Service (NCSS).
|OPeNDAP||Delivers subsetted datasets to OPeNDAP clients||DAP2 and DAP4 Protocol|
|HTTP||HTTP file download server||An integrated server provides bulk file access through the HTTP protocol|
|WCS||Delivers subsetted datasets to Web Coverage Service clients||THREDDS Web Coverage Service (WCS)|
|WMS||Delivers map images to Web Mapping Service clients||TDS Web Map Service (WMS)|
|NetCDFSubset||Interface for choosing and downloading subsetted datasets as NetCDF files||NetCDF Subset Service Reference|
|NCML||NetCDF Markup Language is an XML representation of NetCDF metadata|
|UDDC||Evaluates dataset compliance to the NetCDF Attribute Convention for Data Discovery (NACDD)||TDS and ncISO: Metadata Services|
|ISO||Provides a representation of the ISO 19115 metadata structure||TDS and ncISO: Metadata Services|
NetCDF Subset Service (NCSS)
The NetCDF subset service is both a web service and an interface (UI) that can be used to download part of a file or aggregation in NetCDF format. The interface is accessed via the ‘NetcdfServer’ link in the ‘Access’ section of the dataset’s catalog page. The interface includes a geographic bounding box and options to search by variable, time range, and level. The UI provides a NetCDF download option, and shows an equivalent web service link that performs the same download. This can be used to prototype access URLs for custom client software. CFS has latitude and longitude dimensions, so it will work easily with this tool.
Godiva 2 is a web map integrated with THREDDS that allows users to explore gridded data that follows CF (Climate and Forecast) conventions. This tool works with aggregations and individual files. The UI presents a world map with a color bar, date picker, and a list of variables to plot. To launch the program, navigate to a specific file or aggregation and select “Godiva2” from the list of viewers at the bottom of the dataset page.