The National Geothermal Data System is a network of information providers and consumers connected by agreeing on conventions for data registration, discovery and interchange. Thus there are a wide variety of options for utilizing information from the system; we anticipate that if the system is successful there will be an ecosystem of user applications that utilize data from the system in a wide variety of ways. See the 'Use apps' page for details on using various off the shelf software with NGDS services.
A typical workflow for a user application in the system would present the user with a choice of activities, such as find data, make a map, plot data in a graph, or the application might be specifically designed to support only one of these activities in which case there is no choice to be made. The first step in an actual user process would be to acquire data appropriate to the chosen activity. Applications might be preconfigured with specific datasets, provide a browse tree type search to let users pick datasets from a pre-populated list, or the user might fill in a form that runs a search against the NGDS catalog. Metadata for the various resources must be easily accessible in a user-friendly form to enable the user to choose between similar datasets. After the user selects resources that will be used, that application will utilize information in the metadata and NGDS data access protocols to obtain the desired datasets and the user will work on their project.
The NGDS Design and Build project (BSU) has developed a portal application for data discovery and some basic data browsing and exploration activities, as well as data download (additional apps are in preparation—stay tuned!).
A catalog search client extension for ArcMap provides an example of a plug in approach to adding NGDS search and data access to an existing widely used desktop GIS Application (ESRI ArcMap). The add-in provides a button that can be added to standard ArcMap tool bars. The button opens a search window enabling simple bounding box location and free text search of the NGDS catalog. The client uses the OGC CSW interface to send search requests, and parses returned metadata to identify resources that are distributed using the OGC Web Map Service. The user can select one of these resources and add it to their ArcMap project as a new layer. The code base for this application is on GitHub at usgin/arcmap-cswclient.
NGDS map services can be used with a variety of existing web map applications that allow connection to OGC Web Map services. Some examples include the USGS National Map Viewer, ArcGIS Online, or NREL’s Geothermal Prospector. Web applications can be built using the OpenLayers framework to access and display NGDS data.
The Data-getter is another example web application that will access data delivered through OGC Web Feature services and download subsets of the data as a table that can be cut and pasted into common spreadsheet software. The code base for this application is on GitHub at usgin/wfs-search.