The last open-space development map, published in 2013, serves as the statistical base for the present map with regard to open space losses and gains. This map already covers the areas ‘gained’ between 1945 and 2010 and the areas ‘lost’ for the periods from 1945-1970, 1970-1980, 1980-1990, 1990-2000 and 2000-2010. These areas have been transferred to the new map.
The mapping of open space losses in the first versions of this map prior to 1990 primarily involved the use of non-digital sources. The Environmental Atlas Map 06.03 Open-Space Development since 1950 from the year 1985, which served as the main data base, presents open space losses for West Berlin for the periods from 1950-1970, 1970-1980 and 1980-1984. It indicates open space gains based on the open-space inventory of 1984 (scale 1 : 50,000). This map in turn was based on historical city maps. The city atlas used, Berlin in der Tasche (Berlin in your pocket) around 1950 and 1970 (scale 1 : 20,000 – 25,000), the 1975 Berlin City Atlas (scale 1 : 8,000) and the 1980 Buchplan Berlin Hauptstadt der DDR (Atlas of Berlin, Capital of the GDR) (scale 1 : 25,000), formed the basis for ascertaining the open-space inventory in 1950, 1970 and 1980 in East Berlin. The open-space inventory for both East and West Berlin for the year 1990 was extracted from the Euro-Großraumstadtatlas Berlin 1990 (Euro City Atlas of Greater Berlin) (scale: 1 : 20,000) and the Berlin Stadtplan 1991 (Berlin city map) (scale 1 : 20,000 and 1 : 25,000 – 35,000 respectively).
In addition, the Environmental Atlas Maps “Actual Use of Built-Up Areas” (06.01) and “Inventory of Green and Open Spaces” (06.02), which were developed based on the actual use mapping of the Urban and Environment Information System (ISU) parallel to each version of the open-space development map, were used to define and delimit the inventory of open spaces as well as the losses and gains of open space.
For the current version of the map, a new decade of open space losses (2010-2020) was added to the data and the information on open space gains was updated. The actual-use mappings of the ISU as of 2010 and 2020 formed the primary data base for this purpose.
Aerial photographs and orthophotos from the years 1928, 1953, 1990, 1998, 2002, 2004, 2010 and 2020 (all years are available in the Geoportal of the State of Berlin (SenStadtWohn 2020)) were used to verify individual areas throughout the phases of the map update.