Maritime boundaries are critical elements to the planning of any activity in the ocean realm. From the early 1700ís when the Dutch issued a decree establishing a "territorial sea" which was as wide as "the hypothetical range of an imaginary cannon," nations have sought to control portions of the global ocean which touch their shores. Under evolving criteria being established by the United Nations Convention on the Law of the Sea (UNCLOS), nations continue to re-define their sovereign claims to ocean space.
Many industries and activities recognize the growing importance of maritime claim and boundary delimitation. National claims may overlap, creating areas of disputed ownership and jurisdiction that can lead to confrontation and even open conflict. In the assessment, exploration and recovery of petroleum, mineral, or fishing resources, a distance of a few hundred meters can have significant economic importance. Trespassing a nation's claims could have serious consequences; arrests, fines, ship confiscation, prison, loss of limb or life.
However, the reconstruction of maritime claims and boundaries and their associated jurisdictional aspects is complex, and in many cases, confusing or contradictory. Boundary agreements may take years to develop, often involving third-party mediation. The details and meaning of boundaries may be buried in pages and pages of text.
Until now, graphical portrayal of the claims or agreed boundaries has not been readily available to those involved in marine activities. Third party publishers of claims and boundaries data typically do not include graphics, portray only one boundary per graphic, or limit their graphics to only the agreed boundaries.
More information: http://www.maritimeboundaries.com
The Global Maritime Boundaries Database (GMBD) CD-ROM brings together the claims, limits and boundaries of the world with detailed attribution and documentation so they can be queried and viewed using GIS software. Included in the GMBD are: territorial seas; contiguous, joint development, fishing, and economic zones; potential claim median line solutions, disputed areas, boundary status; and much more.
The value "-9999" corresponds to "No Data".
The data is only aggregated if at least 75 % of the observations are available (i.e. % of population or % of area or % of countries) on an annual basis.
Calculated pre 1991-1992 relative country share
Former Yugoslavia SFR:
World total includes countries not listed and coastline for disputed areas.
Spain includes coastline length for the Canary Islands.
The measurement of an irregular and curving feature such as a nation's coastal length is scale-dependent and very difficult to measure. Maps of individual islands for example, frequently show great detail, whereas regional maps summarize complex coastlines into a few simple lines. In addition, coastal features are constantly changing due to erosion, etc. The only way to derive comparable statistics on coastline length is to use a single source which uses a constant scale. This is what has been attempted with the data presented in this table, however, highly complex coastlines will appear longer at higher resolutions. Estimates may differ from other published sources.
Because of the difficulty in trying to measure coastline length, these figures should be interpreted as approximations and should be used with caution. Coastline length was derived from the World Vector Shoreline database at 1:250,000 kilometers. The estimates presented here were calculated using a Geographic Information System (GIS) and an underlying database consistent for the entire world.
The methodology used to estimate length is based on the following: 1) A country's coastline is made up of individual lines, and an individual line has two or more vertices and/or nodes. 2) The length between two vertices is calculated on the surface of a sphere. 3) The sum of the lengths of the pairs of vertices is aggregated for each individual line, and 4) the sum of the lengths of individual lines was aggregated for a country.
In general, the coastline length of islands that are part of a country, but are not overseas territories, are included in the coastline estimate for that country (i.e., Canary Islands are included in Spain). Coastline length for overseas territories and dependencies are listed separately. Disputed areas are not included in country or regional totals.
Coastal length data are based on the World Vector Shoreline, United States Defense Mapping Agency, 1989. Figures were calculated by L. Pruett and J. Cimino, unpublished data, Global Maritime Boundaries Database (GMBD), Veridian - MRJ Technology Solutions, (Fairfax, Virginia, January, 2000).
Copyright c 2002 (Aggregations) United Nations Environment Programme/DEWA/GRID-Geneva.
Data aggregation made by Andrea DeBono and Ola Nordbeck (UNEP/DEWA/GRID-Geneva).