Geospatial information: how-to
This document describes how to complete ADN geospatial metadata fields when the geospatial feature being described is associated with Earth. Directions on how to catalog locations on other planets or in the solar system will be provided in the future.
When to use geospatial information
Providing geospatial information is not appropriate for every DLESE resource. Use geospatial information when:
That is, don't use geospatial information if a resource talks about tundra and then does not define a specific tundra area. Rather if the resource talks about tundra and then makes a point about a specific area in Canada, then include geospatial information. The same goes for the ozone hole. If a specific areal extent of the ozone hole is mentioned, then include geospatial information.
Types of resources for geospatial information
Generally, the following types of resources benefit most from geospatial information:
Overview of ADN geospatial information
The ADN metadata framework divides geospatial information into two sections:
Both sections need to be completed because bounding boxes should be generated from and encompass detailed geometries. Initially, it is the bounding box information that will be used for digital library search and browse. ADN geospatial information is intended to serve this digital library search and browse; it is not meant for complex representations in GIS systems.
An example: Alaska Volcano Observatory
The Alaska Volcano Observatory provides geospatial information (elevation, latitude and longitude, etc.) on over 50 individual volcanoes. Since there is so much information, this example considers two sections of Alaska, the Aleutian Islands and the Alaskan Peninsula as the areas of interest. Even with just these two sections there are still 20 plus volcanoes. This is still too many volcanoes to individually catalog. Since the Aleutian Islands and the Alaskan Peninsula are recognized geographic areas, this example catalogs each area as a detailed geometry and determines the single overarching bounding box encompassing both areas.
While the resource provides individual latitudes and longitudes for the volcanic points, it does not provide the overarching box' encompassing all the volcanic points nor the coordinates for the Aleutian Islands or Alaskan Peninsula. In this case, a wall map was used to determine the single overarching bounding box. and the detailed geometry boundaries. Based on the wall map, the approximate four edges of a box that encompasses the Aleutian Islands and Alaskan Peninsula. and whose edges are parallel to lines of latitude and longitude are:
Single overarching bounding box
Aleutian Islands detailed geometry
Place name: Aleutian Islands
Alaskan Peninsula detailed geometry
Place name: Alaskan Peninsula
As shown above, place name information may be associated with detailed geometries or the overarching bounding box. Because the overarching bounding box encompasses multiple areas, it is not given multiple areas, it is not given a place name while the detailed geometries are their proper names.
Determining additional overarching bounding box data
To fully specify the single overarching bounding box, other pieces of information are required. These include:
If these data are obtained by reading a wall map or can not be determined readily, then use the following as their values:
If these data are obtained from:
use the following as values:
Completing the metadata fields
Now its time to catalog. This section is geared to resource catalogers using the DLESE Collection System (DCS). However, catalogers or collection builders creating metadata by other means still need to complete the same fields and therefore may find this section helpful in knowing what these fields are.
Overarching bounding box
Single location example
Additional multiple locations example
For any resource that encompasses multiple locations, adjust the bounding box to encompass all of the locations and add additional detailed geometries for each location. An example with three locations is provided below.
The outer bounding box is entered into the bounding box metadata and the longitude and latitude coordinates for Oregon, Mt. Hood, and Colorado are entered into the detailed geometries. The catalog (metadata) record for this example is at: http://dcs.dlese.org/preview/admin/view.do?id=SIC-000-000-000-039. It is often easier to complete the detailed geometries first and then complete the overarching bounding box.
Last updated: 2005-06-09