New Mexico Data Center Embraces Open Architecture

Author: Karl Benedict – Senior Research Scientist
Earth Data Analysis Center, University of New Mexico
MSC01 1110
1 University of New Mexico
Albuquerque, NM 87131USA
Tel: 505.277.3622 x234
Email: kbene@edac.unm.edu
http://edac.unm.edu

The University of New Mexico Earth Data Analysis Center (EDAC), has been providing geospatial data and services for a wide range of uses since 1964. As a longtime partner in the New Mexico Resource Geographic System Program (RGIS) [http://rgis.unm.edu], EDAC has constructed and maintains the state's online spatial data clearinghouse. RGIS is dedicated to advancing applications of geographic information system technology within New Mexico's State agencies and for local government and private industry.

Like most other university-based or state government-based spatial data centers, EDAC has seen steady growth in the requests for both data and services. The statewide clearinghouse managed by EDAC now delivers over 500,000 datasets/year to end users over the Web, and EDAC clients in diverse fields present EDAC developers with a increasing set of application requirements. Application domains include, for example, public health and epidemiology, environmental analysis and mapping, transportation security, air quality, disaster planning and management, and border security and monitoring. The EDAC staff have continually updated the Center's technology approaches to help meet this growing demand. The most significant new technology development for geospatial data centers is the arrival of open interfaces for Web-based geoprocessing architectures.

The open framework for Web-based delivery of data and services that EDAC is building benefits clearinghouse users, clients and application developers. As the different elements of the system come online, Clearinghouse users find it increasingly easy to find, view and access data in the extensive RGIS library. Clients get solutions that leverage both their legacy systems' capabilities and the new capabilities offered by Web Services, and they minimize their technology risk and vendor dependence. Developers are able to efficiently build and reuse service components, thus delivering applications more quickly at lower cost, while leveraging existing EDAC and RGIS resources.

EDAC has developed services implementing the OpenGIS® Web Map Server Specification (WMS) that enable easy viewing of the statewide collection of over 8000 USGS Digital Ortho Photo Quads (DOQQ). These services are being integrated into several client applications and are also being prepared for wider deployment within the clearinghouse. EDAC uses Minnesota MapServer, an Open Source internet mapping application, as the platform for the Web mapping services. MapServer also allows delivery of not just map views but also the actual data -- through planned delivery of mosaiced DOQQs to Clearinghouse users via an interface that implements the OpenGIS® Web Coverage Server Specification (WCS). The OGC standards facilitate the efficient use and management of large datasets (more than 750 gigabytes in the case of the statewide DOQQs) across multiple applications and projects.

OGC standards for delivery of vector data play an important role in a prototype Public Health Distributed Data Management and Mapping application for the New Mexico Department of Health. This application uses services that implement the OpenGIS® Web Feature Server Specification (WFS) to generate Geography Markup Language (GML) representations of census blocks, block groups, tracts and counties that are merged with attributes for those geometries. The attributes are provided by other distributed data providers who use the geometries and attributes in an interactive mapping application. Here and in other applications, interoperability and support for XML facilitate the programmatic integration of OGC Web Service based products into broader applications.

Metadata is an important part of any data library. EDAC has developed FGDC-compliant, XML-encoded metadata for a large portion of its data holdings, and this work continues. This collection of metadata will eventually provide the content for an online spatial data catalog based on the OpenGIS® Catalog Services Specification, and web accessible directories usable by harvesting services such as those used by Geospatial OneStop and the NBII Clearinghouse Nodes.

OGC standards have enabled EDAC to efficiently use large datasets in multiple applications, which increases the value of the data holdings, and helps the Center achieve its public service mission. The standards also facilitate the development of distributed geospatial applications that are built upon an interoperable foundation. This provides great flexibility as new data and data services become available and also provides the ability to further leverage investments made in the development of the open services upon which the applications are based.