Data Services : THREDDS

Thematic Realtime Environmental Distributed Data Services (THREDDS) Data Server (TDS)

TDS logo

Developed by: Unidata, TDS info

Summary:

Our primary data store, TDS serves out an aggregate data set from a collection of NetCDF files in our archive, thereby allowing the end user to subset an arbitrary spatiotemporal range of their choosing. While its focus is on serving rather than viewing data, it does provide links to several data viewers. Behind the scenes, TDS also serves as the input source for some of our other data servers (LAS and ERDDAP).

Suggested use:

  • Download data via OPeNDAP and other data services.
  • Read summary information on data set catalog pages and access links to all of our available data viewers.

Pros:

  • Catalog pages include metadata and other data set documentation.
  • NetCDF Subset Service (NCSS) provides intuitive, RESTful (URL-based), data access with spatiotemporal subsetting options for gridded data.
  • Forecast model run collections can be accessed through a variety of time slices, most useful of which is the “best time series” compiled from the nearest possible model run for any given day.
  • Web Map Service (WMS) provides enhanced capabilities for handling time and depth as well as customizable colors, image stretching (color range), and vector maps (different arrow icons for plotting wind and ocean currents).

Cons:

  • OPeNDAP learning curve.
  • No other services available yet for non-gridded data sets, though NCSS and Sensor Observation Service (SOS) will be offered later in 2012. Tip: For RESTful access to point data, use ERDDAP.

Data offerings:

  • Our most comprehensive repository for time series data.
  • Includes real-time in situ observations (water quality buoys, nearshore sensors, acoustic Doppler current profilers, high frequency radios, autonomous underwater vehicles, and tide gauges).
  • A variety of forecast models, satellite data, and other gridded data like bathymetry.

Screenshots:

Data types:

  • grids
  • points
  • radials
  • trajectories

Services:

  • OPeNDAP
  • gridded data only:
    • Web Map Service (WMS)
    • Web Coverage Service (WCS)
    • NetCDF Subset Service (NCSS)

Output formats:

  • NetCDF (NCSS, HTTP)
  • DODS binary (OPeNDAP)
  • PNG, JPEG, GIF (WMS)
  • KML (WMS)
  • GeoTIFF (WCS)
  • XML (NCSS)
  • ASCII text: comma-separated values (CSV) (NCSS)

Metadata:

  • ISO 19115-2: Geographic Information − Metadata
  • THREDDS Dataset Inventory Catalog Specification
  • CF: NetCDF Climate and Forecast Metadata Convention
  • NetCDF Attribute Convention for Dataset Discovery
  • NetCDF Markup Language (NcML)

Viewers:

  • ncWMS Godiva2 (gridded data only)
  • Integrated Data Viewer (IDV)
  • NetCDF-Java Tools User Interface (UI)
  • direct links to many of our other data servers and viewers
Data Interoperability

Plug-and-play with PacIOOS data in your chosen software or programming language using standardized web services protocols like OPeNDAP, Web Map Service (WMS), Sensor Observation Service (SOS), NetCDF Subset Service (NCSS), and other open access methods. Please contact us at info@pacioos.org if you have any questions!