Urban Climate Zones 2000
Zone 0 basically includes meadows and pastures, farmland, forests, sewage farms and, in individual cases, very loosely cultivated areas with large percentages of vegetation, mainly outside the urban area. One focus is the open heathland and the meadows and pastures west of a line from Hennigsdorf to Potsdam. Also in this zone are Berlin forest areas near the city‘s edge, such as lowland glades or bogs (Bars Lake, Pech Lake, and the Teufelsbruch).
Nocturnal cooling is classified as very high; in forest areas as high. The frost day frequency is also high. Risk of excessive humidity is slight, almost without exception. Lowland areas such as the Döberitz Heath and the Teufelsbruch meadows east of Schönwalde present conspicuous terrain-climatic extreme situations (Zone 0*). Nocturnal cooling and frost day frequency is especially high there.
Both daytime and nighttime wind speeds are considerably lower in closed forest areas. This is also true of non-densely built residential areas with large green areas. Wind reduction in grasslands and fields is moderate to slight during the day, and moderate at night. The formation of strong ground inversion layers during the nocturnal radiation period reduces wind speeds, and thus aeration, considerably.
Zone 1 was the zone which the first edition of this map assumed would reflect open-landscape conditions. In fact, however, the inclusion of the surrounding countryside shows the occurrences of clearly lower mean temperatures and minimum temperatures, as well as greater daily temperature amplitudes. It must therefore now be assumed that areas in Zone 1 are only very slightly influenced by the city. These areas are mainly long stretches of forests located near the city‘s outskirts; large green areas, mostly far from the inner city; a large portion of areas in the surrounding countryside used agriculturally; and large, low-density residential areas outside of Berlin. Some specific large open areas at the edge of the inner city have characteristics of Zone 1, such as the Südgelände, the Prenzlauer Berg Volkspark, Jungfernheide Park, and forest and allotment garden areas around the Königsheide.
Nocturnal cooling and incidence of frost days are generally high here, and, in forest areas, more moderate. The risk of excessive humidity is very slight in most areas of this zone.
Both daytime and nighttime wind-speed reduction in areas of denser vegetation are categorized as very high. Parks near inner-city emission areas are extremely endangered by emissions. Agricultural areas experience high daytime and moderate nighttime wind speeds. Cold air formation here causes stabilization of near-ground air layers during low-exchange nocturnal radiation periods.
Zone 2 use-patterns are largely those typical for the city’s edge, such as low-density and allotment gardens. This zone also includes large inner-city or near-inner-city open space complexes, or parts of them, such as:
- Tempelhof Airport, the Hasenheide, cemeteries, Bergmannstrasse;
- the Südgelände, allotment gardens on both sides of Priesterweg, the Bergstrasse Cemetery, the Insulaner;
- the Tiergarten.
Also assigned to Zone 2 are all major bodies of water; but for technical reasons, only their banks and shores could be used for direct measurements of climatic parameters. Major horizontal gradients across the expanses of bodies of water are not to be expected, however.
Zone 2 is distinguished by moderate nocturnal cooling and frost day frequency. Some portions are located in areas of very slight risk of excessive humidity; most, however, are in areas of moderate risk of excessive humidity. Wind speeds are reduced greatly to moderately throughout the daytime, depending on the vegetation and development structures. Large-surface bodies of water and knolls are very well aerated, and are thus less endangered by emissions.
Zone 3 includes a large part of the inner city’s edge, some areas on the outskirts with high-density development, and also most high-rise residential areas on the outskirts of the city. The inner city area itself has some small parks and vacant areas, but adjacent open spaces and developed edge areas as described in Zone 2 are categorized here.
Nocturnal cooling and frost-day frequency in this zone are slight. The risk of excessive humidity is only moderate, except for a few areas of very slight risk (Olympic Stadium, the northwestern Wuhlheide) or high risk (the Haselhorst, the Tegel industrial area, the Köpenick old town core).
Reduction of daytime and nighttime wind speeds ranges from moderate to slight, depending on building and vegetation structures. Small green spaces are aerated more poorly. Urban vacant areas have higher daytime and greatly reduced nighttime wind speeds, depending on the degree of stabilization of near-ground air layers. Small business and industrial areas with large portions of undeveloped space, and railway areas, are relatively well-aerated all day. High-rise settlement areas must be assumed to have even stronger winds.
Zone 4 includes almost only the very dense inner city, and the heavily built-up and widely sealed industrial areas outside the inner city (such as the Spree Valley industrial area in the borough of Spandau).
In this map, analogously to the statements of the other updated climate maps, the area of strongest inner-city change must now be represented as a closed ring. The previous interruptions related to the connections of the Gleisdreieck area to the Humboldt Port and the area north of the Great Tiergarten can no longer be ascertained, as a result of major construction projects. The limits of Zone 3, which is favorably influenced by the Great Tiergarten, are approximately the Landwehr Canal to the south, Ebertstrasse to the east, and the Moabiter Werder to the north.
Nocturnal cooling and frost day frequency are very slight. There is a high risk of excessive humidity in most of Zone 4.
Reduction of wind speeds during the day can be asseumed to be moderate to slight. The normal wind speed reduction at night is at least delayed because in the street corridors, there is a lesser tendency for the near-ground air layers to stabilize. High winds are generally due to the narrow street corridors. However, this provides no improvement of the air exchange situation, because there is only an insufficient connection to higher air layers, or to the surrounding countryside. Endangerment from emissions is very high because of insufficient aeration, especially within closed development structures.