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
