About ADL

The Alexandria Digital Library (ADL) is a consortium of researchers, developers, and educators, spanning the academic, public, and private sectors, exploring a variety of problems related to a distributed digital library for geographically-referenced information.

Distributed means the library's components may be spread across the Internet, as well as coexisting on a single desktop. Geographically referenced means that all the objects in the library will be associated with one or more regions ("footprints") on the surface of the Earth.

Mission Statement

To provide a federated spatially searchable digital library of geographically referenced materials. The library's components may be distributed (spread across the Internet) or coexist within a single network or desktop. Geographically-referenced means that all the information objects in the library will be associated with one or more regions ("footprints") on the surface of the Earth.

Brief History

The name Alexandria comes from the library of Alexandria, Egypt, which was considered the center of all knowledge/learning. No one place now can claim that distinction—but all data sources together (libraries, academic institutions, private companies, government agencies, etc.) are Alexandria. The project began in 1995 with the development of the Alexandria Digital Library, a working digital library with collections of geographically referenced materials and services for accessing those collections. The original Alexandria Digital Library is headquartered on the campus of the University of California at Santa Barbara and is hosted by the Davidson Library's Map & Imagery Lab. The MIL team is working with development teams throughout the world to establish remote, independent, yet federated ADL nodes in which local collections can be added and maintained easily and effectively.

Current Collections

ADL teams throughout the world are in the process of loading significant collections of geospatially-referenced information. The construction of varied and useful collections is necessary for a variety of research purposes as well as for an operational digital library, which entails our collections being extensive in order to provide appropriate coverage.

An important focus for ADL's collection is on information supporting basic science, including the Earth and Social Sciences. The datasets that we are in the process of loading include:

New Zealand Node

Scanned Aerial Photographs

United States

Scanned Aerial Photographs (mainly Southern California)
Digital Elevation Models (DEMs)
Digital Raster Graphics (DRGs)

World Wide

Landsat TM (UCSB Film Holdings)
World Maps from the United States Central Intelligence Agency
AVHRR & MODIS Satellite Scenes
Ocean Drilling Program Cruise Information
PEGASUS (UCSB Library) map records

Criteria for Inclusion in ADL

ADL's guidelines for the selection of materials for its collections include:

the content of the materials should involve significant georeferencing representable by "graphical footprints" on some map
the content should be of value to some well-defined, accessible set of users
for the mostpart, the materials should be unique, or not otherwise available, and focused on "local" areas, with decreasing density of coverage with distance from the geographical locations of the ADL nodes
the materials should showcase ADL's research and development mission, involving distributed collections of heterogeneous data types (multimedia), heterogeneous (distributed) search and post-retrieval processing
the materials should involve, if possible, a minimal support burden for ADL, and focus on unencumbered items already in digital form that have the potential of being scaled to collections with large numbers of item

There will be exceptions to these guidelines. For example, we will grow ADL's collections in part by digitizing analog materials and we will also load materials that are encumbered to demonstrate our ability to handle intellectual property rights issues.