The NOAA GEO-IDE UAF ERDDAP

NOAA (the National Oceanic and Atmospheric Administration) is the U.S. federal agency with a mission to understand and predict changes in Earth's environment and conserve and manage coastal and marine resources to meet our Nation's economic, social, and environmental needs.

GEO-IDE (the NOAA Global Earth Observation - Integrated Data Environment initiative) is a set of guidelines and best practices that establish a framework for improving the interoperability of NOAA's environmental information management resources. GEO-IDE is a project of the NOAA Data Management Integration Team (DMIT).

UAF (the Unified Access Framework) is a NOAA-wide effort to develop a gridded dataset integration capability. The capability is being developing using several de facto standards: netCDF, which provides the abstract data model, software libraries and a persistent binary format; the Climate and Forecast (CF) metadata conventions; the OPeNDAP protocol for web transport of data subsets; THREDDS XML catalogs which provide a distributed topology connecting data suppliers; and an OGC compatibility layer that provides access to the grids through WMS and WCS.

The initial focus has been to develop a NOAA-wide UAF THREDDS catalog of CF-compliant datasets (e.g. model outputs, satellite products, High Frequency radar observations, etc.) and to connect the catalog to other data servers (e.g., LAS and ERDDAP (this web site!)) and several popular client tools (e.g. MatLab, Google Earth) to enable direct access and use of the datasets.

ERDDAP is a data server that gives you a simple, consistent way to download subsets of scientific datasets in common file formats and make graphs and maps. This ERDDAP installation makes all of the datasets in the NOAA-wide UAF THREDDS catalog and many additional datasets available via ERDDAP. The added benefits of using ERDDAP are:

• More Search Options - ERDDAP gives you many ways to search for interesting datasets (see the options at right), instead of just a tree (hierarchical) list of the datasets.
   
• More File Formats - ERDDAP gives you the ability to download subsets of the datasets in many common file formats (for example, .html table, ESRI .asc, Google Earth .kml, .mat, .nc, OPeNDAP .asc and .dods, .csv, .tsv, .json, and .xhtml) instead of just the OPeNDAP ASCII and binary formats.
   
• A Consistent Time Format - In ERDDAP, time when formatted as a number is always in "seconds since 1970-01-01T00:00:00Z" (which is UDUNITS-compatible) and,
  when formatted as a string, time is formatted according to the ISO 8601:2004 "extended" format standard
  (YYYY-MM-DDThh:mm:ssZ, for example, "1985-01-02T00:00:00Z").
  Also, to avoid time zone and daylight savings time confusion, time values are always converted to the UTC (GMT/Zulu) time zone.
  This makes it easy to specify time constraints in requests without having to worry about the time format (a nightmarish realm of possible formats and time zones).
  And this makes the results from different data sources easy to compare.
   
• Custom Graphs and Maps - ERDDAP gives you the ability to make customized graphs and maps. (See the Make A Graph option for each dataset.)

To see ERDDAP and UAF in action, watch the first half of this video.

Find out more about ERDDAP.

Start Using ERDDAP:
    Search for Interesting Datasets

• Do a Full Text Search for Datasets

  Search Hints

  • This is a Google-like search of the datasets\' metadata:  Type the words you want to search for, with spaces between the words.  ERDDAP will search for the words separately, not as a phrase.
  • To search for a phrase, put double quotes around the phrase (for example, "wind speed").
  • To exclude datasets with a specific word, use -excludedWord . To exclude datasets with a specific phrase, use -"excluded phrase" .
  • Don\'t use AND between search terms. It is implied. The results will include only the datasets that have all of the specified words and phrases (and none of the excluded words and phrases) in the dataset\'s metadata (data about the dataset).
  • Searches are not case-sensitive.
  • To search for specific attribute values, use attName=attValue .
  • To find just grid or just table datasets, include protocol=griddap or protocol=tabledap in your search.
  • This ERDDAP is using searchEngine=original.
  • In this ERDDAP, you can search for any part of a word. For example, searching for spee will find datasets with speed and datasets with WindSpeed.
  • In this ERDDAP, the last word in a phrase may be a partial word. For  example, to find datasets from a specific website (usually the start of the datasetID), include (for example) "datasetID=erd" in your search.

  ')" onmouseout="UnTip()" > Search

• View a List of All 9,043 Datasets

• Search for Datasets by Category

  Datasets can be categorized in different ways by the values of various metadata attributes. Click on an attribute (cdm_data_type, institution, ioos_category, keywords, long_name, standard_name, variableName) to see a list of categories (values) for that attribute. Then, you can click on a category to see a list of relevant datasets.

• Search for Datasets with Advanced Search Advanced Search combines all of the search techniques and adds searches for datasets that have data within longitude, latitude, and time ranges, so you can search for datasets based on many different criteria simultaneously.')" onmouseout="UnTip()" >

• Search for Datasets by Protocol

  Protocols are the standards which specify how to request data. Different protocols are appropriate for different types of data and for different client applications.
   

  Protocol	Description
  griddap datasets	Griddap lets you use the OPeNDAP hyperslab protocol to request data subsets, graphs, and maps from gridded datasets (for example, satellite data and climate model data). griddap documentation
  tabledap datasets	Tabledap lets you use the OPeNDAP constraint/selection protocol to request data subsets, graphs, and maps from tabular datasets (for example, buoy data). tabledap documentation
  "files" datasets	ERDDAP's "files" system lets you browse a virtual file system and download source data files. WARNING! The dataset's metadata and variable names in these source files may be different than elsewhere in ERDDAP! You might prefer using the dataset's Data Access Form instead. "files" documentation
  WMS datasets	The Web Map Service (WMS) lets you request an image with data plotted on a map. WMS documentation

   

• Developers of computer programs and JavaScripted web pages can search for datasets via

  • ERDDAP's RESTful search services
  • ERDDAP's allDatasets tabular dataset that has a row of information for each dataset
  • ERDDAP's OpenSearch 1.1 Service

• Search Multiple ERDDAPs

  There are two unofficial ways to search multiple ERDDAPs for datasets: Search Multiple ERDDAPs and ERDDAP Dataset Discovery.

Converters
In addition to serving data, ERDDAP has some handy converters:

Metadata
ERDDAP has an
FGDC Web Accessible Folder (WAF) with FGDC‑STD‑001‑1998 metadata files and an
ISO 19115 Web Accessible Folder (WAF) with ISO 19115‑2/19139 metadata files for all of the geospatial datasets in this ERDDAP.

RESTful Web Services
You can bypass ERDDAP's web pages and use ERDDAP's RESTful web services (for example, for searching for datasets, for downloading data, for making maps) directly from any computer program (for example, Matlab, R, or a program that you write) and even from web pages (via HTML image tags or JavaScript). RESTful Web Services documentation

Other Features