DIVER Data Services
For data services, DIVER uses ERDDAP, an open-source data server program developed by NOAA’s Southwest Fisheries Science Center that gives users a simple, consistent way to download scientific data in common file formats. High-volume data users can directly access the public data stored in NOAA’s DIVER (Data Integration Visualization Exploration and Reporting) warehouse and query tool. ERDDAP queries are very flexible and may be optimized for users seeking large data downloads or specific queries related to a known dataset. Because ERDDAP users may view all exposed database fields, it is best if the user has prior knowledge of how the data are structured, including valid values of interest.
Using ERDDAP
Each dataset corresponds to a DIVER regional data category and has multiple associated links.
- Data allows the user to query data through the Data Access Form.
- Graph allows the user to create graphs and maps of available data.
- Metadata provides the user with dataset-level information in FGDC, ISO 19115, and .html formats.
- Background links the user to information on dataset organization.
Before beginning a query, users should review the DIVER Data Overview and DIVER Environmental Data Specification to better understand the data structure. Users can also create lists of current values by running a query on a specific field, as in Example 1 below.
The Data Access Form uses OPeNDAP constraint protocols to access data within DIVER. Because ERDDAP pulls data directly from DIVER, the data structure and fields (variables) are the same. Users query data using common operators and server-side functions. Users determine the grain of data returned through the constraints that they set. Data cannot be queried across regions or data categories.
In addition to providing access to large data downloads, ERDDAP can be used to answer many basic questions. Example questions and data access forms are provided below, with further description in our help materials:
- What are the valid values for Collection Method for samples in the Great Lakes? (Link to Data Access Form)
- What studies took place in Howards Bay between 2010 and 2018? (Link to Data Access Form)
- How many results are associated with each Station/Site for the studies in the "Great Lakes (Mussel Watch)" Case/Activity? (Link to Data Access Form)
- Where are sediment samples located in the Lower Duwamish River study group? (Link to Data Access Form)
- What PCB data are available for surface sediment in the Hudson River station group? (The data table output replicates a single contaminant query in DIVER Explorer.) (Link to Data Table)
To see how to query these questions and for more information about creating queries, view our help materials here.
Further Details
ERDDAP URLs completely describe queries, allowing users to create and share queries with only a URL.
Queried results can be exported in a variety of formats (e.g., .csv, .html, .json), which can be specified in the Data Access Form or by changing the file type directly in a URL.
Metadata for ERDDAP is provided at the dataset level and is not specific to queries. Metadata is available in FGDC, ISO 19115, and .html formats and can be accessed from the dataset page or at the top of each Data Access Form. Supporting information such as notes and references for individual studies and qualifier code definitions can be downloaded from the dataset page as well.
Further information can be found in ERDDAP documentation here. ERDDAP is an open-source program using OPeNDAP and Java, so guidance can also be found by searching online.