Global Access and Distribution of Geospatial Information:
An Operational Reality
Abstract
Social demands from the environmental and resource management sectors have forced data managers to consider how to provide integrated to remotely-sensed and other complementary spatial data stored in disparate archives, databases and GISs. The problem is not trivial in that Earth observation and other complementary spatial data is noted by its diversity and complexity. A plethora of image and FIS models and that can never be practically converted? These challenges can be geospatial information that is independent of the physical storage structure and semantic context of the stored data.
Land Data BC and CEO Net are two distint system that address these same challenges from different perspectives. Both of these systems are running operationally, providing global access and distribution of geospatial information 24 hours a day via World Wide Web (WWW). Expansion continues as more data sources, value-sdded suppliers and services are added.
Introduction
Over the part few years the Earth observation market has been growing as remotely-sensed data is increasingly combined with other forms of spatial/temporal information and is being used by more people around the world. Until recently, Earth observation data has been exploited mostly by the non-renewble resources sector. As new data sources become available, providing better resolution and higher accuracy, the demand for Earth observation data in the renewable resoure\ces sector is increasing (i.e., agriculture, forestry). Applications areas for remotely sensed data now include non-traditional disciplines such as urban planning, enforcement and insurance - just to name just a few.
Accessing and distribution spatial data has been plagued by the difficulties of identifying what is available, where it is located, how it can be obtained and, once obtained, combining it and using it with other data or applications.
How can organizations provide effective and flexible sharing, exchange and dissemination of data? The solution proposed is an umbrella data management system that connects to existing (heterogeneous) spatial information system. Such a system provides a "single-window" view of remotely-sensed and complementary information while allowing custodians to retain control over their data. The solution offer users and suppliers a single, one-stop access and distribution vehicle for products and services.
The Concept
At the most level, the system provides a common infrastructure on top of the Internet allowing users with varying computing equipment to browse and access data/products. Request desired data and receive the data in selectable formats.
The system leta users know what data/products exists, for what geographic areas and how to get the data, even if the information is part of another Earth observation network. The concept is illustrated below.
Access to data and value added products is available to anyone with a PC or workstation equipped with Netscape Navigator or Internet Explorer.
After identifying what information is available, the user has the option of requesting the data. If the data is available in a digital form (e.g., an image or map), the requested data will be electronically " delivered" to the user. If the data is not available form (e.g., a study paper, a paper map, an air photo), the request would be forwarded to a custodian that would handle the request manually by post delivery or fax
The architecture is extensible, flexible and expandable, and is adaptable to any organization. This is beyond theory and prototyping for MacDonald Dettwiler who has designed, implemented and delivered a number of geospatial information system. Two of note are:
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LandData BC-a system that provides consistent, uncomplicated access to land-related information held by the various agencies and ministries of the Province of British Columbia, Canada.
- CEONet (Canadian Earth Observation Network) -a Canada-wide spatial data network that provides integrated access to Earth observation archives and other complementary spatial database, both within Canada and internationally.
