METADATA FILE I. General description of data set ----------------------------------- Name Sub-watershed Drainage Basins for Baltic Sea drainage basin region Geographic Level Regional Specific Area Baltic Sea drainage basin region Lat/Long Region Boundaries NW-X: 0-E , SW-X: 0-E NW-Y: 75-N , SW-Y: 45-N SE-X: 40-E , NE-X: 40-E SE-Y: 45-N , NE-Y: 75-N Infoterra Keyword(s) Watershed management (12670) Natural drainage systems (13140) Catchment areas (13210) Run-off and seepage (13326) Inorganic pollutants (22134) Land pollution (12124) Human population (14213) Other Keyword(s) Nutrient loading, land cover, population Primary Data Acquisition Period Start Date: 1986 End Date: 1986 Supplier GRID-Arendal. PO Box 1602, Myrene. N-4801 Arendal, Norway. Contributor GRID-Arendal. PO Box 1602, Myrene. N-4801 Arendal, Norway. Publication Reference Langaas, S. 1993. Some Georeferenced Data Sets for use within Sub-project 1; Land Use and Ecological Carrying Capacity, of the Baltic Drainage Basin Project. Technical Note. GRID-Arendal. 10 pages + apps. Sweitzer, J., Langaas, S., and Folke, C. 1996. Land Cover and Population Density in the Baltic Sea Drainage Basin: A GIS database. AMBIO, 25(3):191-198. Stalnacke, P. 1994. Documentation of data sources and data quality in the calculation of the land based loads of eutrophying substances to the Baltic Sea, 1970 - 1990. Note, Dept. of Water and Environmental Studies, Linkoping University. 15 pages (in Swedish/English). HELCOM. 1986. Water balance of the Baltic Sea. Baltic Sea Environment Proceedings No. 16., The Helsinki Commission, Finland. 174 pages. Documentation (overview) The main Baltic Sea drainage basin map was created by M. Falkenmark and Z. Mikulski (HELCOM 1986). Both map projection and scale are unknown. Independent measurements indicate a scale of approximately 1:5,000,000. Two additional maps were used to provide more accurate delineations in the Danish Straits and Kattegat sub- regions. These paper maps were also of unknown scale and projection. The Digital Chart of the World (DCW) by ESRI was used for spatial positioning when joining all data sets. These map sources identified 81 sub-basins, which can be aggregated to seven major watersheds for the following major water bodies that define the Baltic Sea: Bothnian Bay, Bothnian Sea, Gulf of Finland, Gulf of Riga, the Baltic Proper, Danish Straits, and the Kattegat. The main Baltic Sea drainage basin map was digitised and transformed in three separate sections using PC ARC/INFO. The Root Mean Square (RMS) error ranged between 0.01 and 0.02. Four sub- basins from the Danish Straits and nine from the Kattegat paper maps were digitised. The RMS errors were 0.01 and 0.06, respectively. All sections were joined together using the APPEND command. Although some RMS errors were high, the final drainage basin data set lines up well with other coverages in the database. The coverage was edited for dangling arcs and label errors. When the editing process was complete, topology was created using the CLEAN command with a 20 meter fuzzy tolerance and dangle length. All polygons were assigned unique id's before attribute data was added. An item called SUBID was added to the coverages .PAT file. This value represents the sub-basin or water body for which each polygon belongs. SUBID served as a bridge item to join additional attributes that existed in an EXCEL spreadsheet. Individual SUBIDs were assigned by selecting polygon label points in ARCEDIT and CALCing SUBID to be the correct value. Extensive error checking was performed before all other attribute data was appended. In addition to the added item SUBID, 21 other attributes were appended to the cover .PAT file. These attributes originated from (a) and database of monthly loads of land based eutrophying substances (Stalnache, 1994), (b) data extracted from the Land Cover data set, and (c) data extracted from the Population Distribution data set. The final BASINS coverage has a total of 26 attributes, including the four automatically generated by ARC/INFO. ************************************************************************ Contact information Hugo Ahlenius phone: +47-370-35650 UNEP/GRID-Arendal fax: +47-370-35050 e-mail: mapmaster@grida.no II. Detailed description of data set (members) ----------------------------------------------- Data set type ArcView shape-file Description BASINS - Sub-watershed Drainage Basins for whole Baltic region File Size ArcView shape: 1,200 KB Access Free access, unrestricted Copies (available sites) CD-ROM - being distributed by GRID-Arendal World Wide Web (WWW), GRID-Arendal URL - http://www.grida.no III. Technical information about vector data --------------------------------------------- Source Data set 3 paper maps with unknown scale and projections Scale/Resolution Approximately 1:5,000,000 Feature Type Polygon Number of Polygons 199 Projection Name Lambert Azimuthal Equal Area Projection Parameters Units: meters Spheroid: International 1909 Radius: 6,378,388 Longitude of centre of projection: 20.00.00 Latitude of centre of projection: 60.00.00 False Easting: 0 False Northing: 0 Projection boundaries Xmin: -725,442 Ymin: -1,221,461 Xmax: 941,380 Ymax: 1,044,857 Attributes Brief description Area,13,13,n,6 Area of polygon Perimeter,13,13,n,6 Perimeter of polygon Basins_,11,11,n,0 Internal coverage record value Basins_id,11,11,n,0 Internal coverage polygon ID Majid,3,3,n,0 Major sub-basin ID Subid,3,3,n,0 Meso-scale sub-basin ID Descript,25,25,c,0 Character description of sub-basin Tot_sbarea,12,12,n,3 Total sub-basin area (sq. km) Ave_runoff,10,10,n,3 Average runoff in x10^6 m^3 /year Std_runoff,10,10,n,3 Standard deviation for average runoff Ave_tot_N,10,10,n,3 Average total N load in tonnes / year Std_tot_N,10,10,n,3 Standard deviation for average total N Ave_tot_P,10,10,n,3 Average total P load in tonnes / year Std_tot_P,10,10,n,3 Standard deviation for average total P Forest,10,10,n,3 Total forested area (sq. km) Arable,10,10,n,3 Total arable land area (sq. km) Pasture,10,10,n,3 Total pasture land area (sq. km) Urban,10,10,n,3 Total urban area (sq. km) Lakes,10,10,n,3 Total lakes area (sq. km) Glacial,10,10,n,3 Total glaciated area (sq. km) Tundra,10,10,n,3 Total tundra area (sq. km) Non_pro_ol,10,10,n,3 Total non-productive open land area (sq. km) Unknown,10,10,n,3 Total unknown land (sq. km) Total_pop,12,12,n,0 Total population within sub-basin Urban_pop,12,12,n,0 Urban population within sub-basin Rural_pop,12,12,n,0 Rural population within sub-basin