While in the 1993 edition (cf. Map 04.07, SenStadtUm 1993g) still could be spoken of a two-splitted heat-island; now serious changings have been arisen in result of the urban development.
A climatic relief function comes from two different open space types:
Area 1a includes islands within the climatic load area, through which up to now have prevented the formation of a closed inner city heat island in Berlin. These spaces are of particular importance in this regard
- Tiergarten/ Zoological Garden,
- Tempelhof Airport / Hasenheide/ cemeteries Bergmannstraße and
- Gleisdreieck to the north and south of the Yorckstrasse.
Examples for further important open spaces are the palace gardens Charlottenburg and the vacant and barren areas in Marzahn and in the industrial area Hohenschönhausen. Beside a multitude of smaller areas which are to be included, such as Kleistpark in Schöneberg or the Volkspark in Mitte, there also individual minute areas, which cannot be depicted at this scale, for which the described functions and characteristics nonetheless also fundamentally apply.
The area 1b includes largely undeveloped green areas on the outskirts of town and in the surrounding countryside. Above all in Weißensee and Pankow they reach from the former sewage farms and agricultural areas far into the urban area. A further important equalizing space is in the urban area formed by the up to now only sparsely built-up single-family settlements in Mahlsdorf-South and Kaulsdorf-South together with the adjacent Krummendammer Heide. Also the remaining inner city forests can be so classified. Wide-scale relief areas lie outside the urban area. On account of the former wall strip, here they border partly directly on the settlement areas of the city (e.g. large-scale settlement Gropiusstadt or high-rise development at the Tirschenreuther Ring in Marienfelde).
Climatically relieved areas (area 2) are subject either to the influence of the relief area 1b or are presently hardly climatically burdened because of their low degree of sealing and high amount of vegetation. In the urban area itself are only relatively few areas, such as Kladow, Lichterade, Rahnsdorf and Schmöckwitz are so classified. By far greater part of the relieved areas lies in the surrounding countryside near Zepernick, Neuenhagen, Schöneiche, Eichwalde/ Zeuthen, Blankenfelde, Teltow, Falkensee, Stolpe and Schildow.
In terms of area, the largest share of the inner city take the form of climatic transition areas (area 3). Beside all larger bodies of water, they include above all areas on the outskirts of town, in so far as they are subject to more intensive development, but still no congestion. (e.g. Staaken, Heiligensee, Buchholz, Karow, Mahlsdorf, Rudow, Buckow, Marienfelde, Zehlendorf). In the northeast and east of the city, the transition area extends to quite near the center of town (Prenzlauer Berg, Rummelsburger Bucht).
A mostly very dense development, joined with a high degree of sealing and an only slight vegetation share mark the climatic load area. This includes core areas of the city, whereby the east part with the exception of the borough Mitte is burdened only slightly. In this central section there are still extensive areas which are not excessively built-up. Areas outside the inner city which can be classified as stressed are distinct concentrations, for example the Spandau old town or the area Niederschöneweide. Two areas can be distinguished according to the degree of the climatic load.
Area 4a includes built-up areas of varying density, in part also climatically overloaded smaller open spaces, industry and small business areas, which display moderate to highly urban climatic characteristics. As a rule these areas border on the most heavily burdened area of 4b. In certain spaces, however, they are themselves the most heavily burdened areas. This is above all in the very congested parts of town lying on the outskirts (Zehlendorf, Friedrichshagen, Hellersdorf, Buch) and in the surrounding countryside (Potsdam suburban housing development, parts of Babelsberg, Schönefeld and Hennigsdorf). In this area not only is the sensitivity toward use intensifications high, rather climatic improvements must be made as part of building and rehabilitation measures. This affects the improvement of ventilation and likewise an increase in the presently meager amount of vegetation.
Area 4b delimits the urban areas, in which the highest negative changes in the radiation and heat balance as well as in the air exchange conditions is to be expected. Large parts of the inner city boroughs Tiergarten, Wedding, Prenzlauer Berg, Mitte, Friedrichshain, Kreuzberg, Tempelhof, Schöneberg and Charlottenburg form an urban heat island, which is ameliorated solely by the large green and open spaces of the relief area 1a. The sensitivity with respect to use intensifications is very high throughout. The improvement of the climatic situation must be given highest priority in building and rehabilitation measures.
Only an isolated incidence of relief-influenced airstream channels is to be expected because of the slight relief differences in Berlin. More decisive than the relief are e.g. the roughness of the terrain and the relationship between height and width. Thus the broad courses of the river Havel and the Spree flats can be said to function as effective airstream channels. However, this also applies to less distinctive streams like the Wuhletal, Teltow and Landwehr canal. Similar channel functions are also to be expected from the lines of the city rail (S) and long-distance railways as well as by individual green areas. The broad road network typical for Berlin is unfit for these purposes because of the high pollution load. Suitable and if necessary locally monitored airstream channels should be kept free of congestion, obstructive development and emissions. Also the green spaces lying in sphere of influence of the channels should be structured as openly as possible.
Extensive cold air movements (plain winds) can occur fundamentally in the impact area of all larger green spaces. In this map such air movement is presented however only for green spaces within and/or in direct vicinity of the exposure areas. As already shown, it does not deal with individually detected incidents, but with assumed movements.