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The original World Data bank (WDb) 2 product was digitized between 1972 and 1977 by the U. S. Department of State's (DoS) Central Intelligence Agency (CIA), and released to the public in the latter year. While the nominal scale of maps used for WDb-2 was one to 3 million (1:3,000,000), parts of Europe, Central America, Southeast Asia and the Middle East were digitized at 1:1,000,000, and the former northeastern USSR and Antarctica were input at 1:4,000,000. The GRID version of WDb-2 is in an ARC/INFO 'EXPORT' format and contains a series of geographical areas (Asia and Australia; Africa and Europe; North and South America), each of which includes a variety of thematic coverages as follows:
- Coastlines, Islands and Lakes - Rivers; major, minor and other - National boundaries - Internal boundaries (some areas only) - Roads (some areas only) - Railways (some areas only)
WDb-2 uses map scales from 1:1,000,000 to 1:4,000,000; nominally, a scale of 1:3,000,000 was used to achieve the amount of detail desired. A total of 19 coverages ('EXPORT' data files) are available, and all data have been kept in their original line topology; that is, no data have been converted to polygons. Users who require boundary-related data in polygon format (e.g., country polygons) are encouraged to obtain the generalized version of World Boundaries from GRID instead.
WDb-2 is recommended for users who need detailed boundary data at the continental, regional or national level. Users who need less detailed boundary data at a global level only are again referred to the more generalized version, which has sufficient detail for global-scale applications. Typically, users of WDb-2 have a study area within a single continent or region. Although most large countries exhibit reasonably detailed features (administrative boundaries, rivers, roads and railways) within their boundaries, many smaller countries do not. Also, some of the WDb-2 coverages are inconsistent at the national level, and many countries lack at least one of the thematic types of information (e.g., internal boundaries and/or roads) altogether.
WDb-2 consists of the following coverages:
AMALLBDY Americas (all); National Boundaries AMALLINT Americas (all); Internal Boundaries AMALL_RR Americas (all); Railways AMCENROA Central America; Roads AMNORCIL North America; Coastlines, Islands and Lakes AMNORRIV North America; Rivers, major-minor-others AMSUDCIL South America; Coastlines, Islands and Lakes AMSUDRIV South America; Rivers, major-minor-others
ASIA_BDY Asia; National Boundaries ASIA_INT Asia; Internal Boundaries ASIA_CIL Asia; Coastlines, Islands and Lakes ASIA_RIV Asia; Rivers, major-minor-others ASIA_ROA Asia; Roads ASIA_RR Asia; Railways
AF_BDY Africa; National Boundaries AF_INT Africa; Internal Boundaries AF_CIL Africa; Coastlines, Islands and Lakes AF_RIV Africa; Rivers, major-minor-others AF_RR Africa; Railways
EUR_BDY Europe; National Boundaries EUR_CIL Europe; Coastlines, Islands and Lakes EUR_INT Europe; Internal Boundaries EUR_RIV Europe; Rivers, major-minor-others EUR_ROA Europe; Roads EUR_RR Europe; Railways
Code descriptions for the various attributes are as follows:
CIL - Coastlines, Islands and Lakes
01 Coastlines, islands and lakes 02 Additional major islands and lakes 03 Intermediate islands and lakes 04 Minor islands and lakes 06 Intermittent major lakes 07 Intermittent minor lakes 08 Reefs 09 Salt pans, major 10 Salt pans, minor 13 Ice shelves, major 14 Ice shelves, minor 15 Glaciers
RIV - Rivers; major, minor and others
01 Permanent major rivers 02 Additional major rivers 03 Additional rivers 04 Minor rivers 05 Double-lined rivers 06 Intermittent rivers, major 07 Intermittent rivers, additional 08 Intermittent rivers, minor 10 Major canals 11 Canals of lesser importance 12 Canals, irrigation type
BDX - National Boundaries or Limits of Sovereignty
01 Demarcated or delimited 02 Indefinite or in dispute 03 Other line of separation or sovereignty on land
BDI - Internal Boundaries
01 First-order administration
For Roads (ROA) and Railways (RR), no special codes exist.
The reference to this data set is as follows: "CIA, 1972. World Data bank 2. Central Intelligence Agency, Washington, D.C. USA."
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