Berlin Environmental Atlas
04.11 Climate Model Berlin - Evaluation Maps (Edition 2009)
Map 04.11.2 Planning Advices Urban Climate
The Planning Advices Urban Climate Map is an integrated evaluation of the facts relevant to planning shown in the Climate Functions Map. Protection and development measures for the improvement of the climate and also - by means of attenuation and removal effects - of the air. The goals of
- Development and
- Reconstruction of
climatic and immissions-ecologically important surface structures (Mosimann et al. 1999) correspond to the main idea of these efforts. The associated planning advices provide information on the sensitivity against usage changes from which climate-founded requirements and measures in the course of areal planning can be deduced. With regard to the adaptions to the climate change, these findings shall furthermore help to make the necessary planning regulations.
Below, the planning classification of climate-relevant elements in Berlin is considered. Detailed, block-related planning recommendations can be found in the digital version of the planning advices map.
Green- and open space inventory
Urban green spaces and green spaces near settlements have a substantial effect on the urban climate and positively influence the direct surroundings micro-climatically. Larger coherent green spaces constitute the climatic regeneration potential. The produced cold air mass flow as a qualifying parameter, however, takes a back seat in this regard. The spatial position and with it the question which bioclimatic load a respective building development involves, is much more important for a classification in the planning process. Ultimately, a green space with only minor production of cold air can also bring with it a significant benefit in densely settled areas.
Of very high importance concerning the urban climate are green and open spaces with an impact on bio-climatically stressed settled areas. These are above all large, inner-city green spaces such as Großer Tiergarten and Volkspark Friedrichshain, and open spaces on the premises of the Airport Tempelhof. Vitally important are furthermore smaller parks, ruderal areas and wasteland, as well as sports grounds that are only sealed up to a moderate extent, as far as they can achieve a relieving effect on the neighbourhood. This results in the highest sensitivity of these areas against intensification of utilisation and the following planning advices:
- Avoidance of exchange barriers against built-up border areas,
- Reduction of emissions and
- Cross-linking with open spaces.
This means that edificial works and utilisation contributing to the sealing of these areas can lead to further alarming climatic damage. Alongside the aforementioned and other individual areas of this class the larger distant areas such as open spaces adjoining Blankenfelde or in the Wuhlheide can also be assigned to this category.
Green and open spaces with a connection to urban areas with a low level of pollution or even a favourable microclimate possess a high to medium importance to the urban climate. They are mostly located in a considerable distance from the city centre and are connected to the urban areas with a minor bio-climatic load that is situated beyond the course of the outer urban railway line (S-Bahn-Ring). Among these are the following areas:
- Green spaces and suburbs pervaded by greenery between Bucher Forest and Malchow,
- Krummendammer- and Köpenicker Bürgerheide,
- Forest Grunewald northwest of the Avus as well as Jungfernheide and
- Forest Spandau.
These areas possess a high sensitivity regarding utilisation intensification, whereby air exchange with its surroundings should be especially considered.
The third category constitutes green and open spaces of low urban climatic importance. These are areas which either possess a minor influence on - burdened - developed settlements, or have an insignificant cold air production. The latter can often only offer a small area size and are usually situated in the inner city. These areas can by all means take on a role as climatically ecological comfort islands, provided that they feature micro-climatic diversity (e.g. bodies of water, shadowed and sunny areas).
The green-shaped development relevant for urban climate represent larger areas with a low sensitivity (cf. climatically favourable settlement areas). As far as they do not border directly on loaded areas, a further development, which does not affect local air exchange considerably, would only result in minor changes in urban climate.
Climatically favourable settlement areas are sparsely developed and green settlements, e.g. mansions with a low sealing level, a high vegetation level and a relatively high nocturnal cooling rate. These areas are cold air producers themselves, to a certain extent, and aid the cold air flow of neighbouring open spaces. Green settlements are usually found outside of the S-Bahn-Ring, but some are near the city centre (e.g. Garden City Tempelhof west of the Airport). These areas lead neither to an intensive bio-climatic impact, nor do they impede air exchange. Thus they mostly show a low PMV-value, which is the basis for the evaluation of the bioclimatic situation into four classes (most favourable / favourable / less favourable / unfavourable) according to VDI-guideline 3785 ist.
The bioclimatically most favourable development usually has a medium sensitivity against utilisation intensification, as long as the building heights are kept low and the parts of the structures are aligned to the cold air flow. Spaces bordering directly on burdened areas will have a high sensitivity due to the climatic relevance.
The bioclimatically favourable development is also among the minor loaded settlement area, but do not constantly show a cold air ventilation. If these areas border on stress areas, this will result in a high sensititvity in respect of use intensification and the avoidance of further densification. If there is no immediate vicinity to loaded areas, there is only a low sensitivity to structural alteration.
Stress areas, on the other hand, usually exhibit ventilation deficiencies and an above-average heat load. These are divided into settlement areas with the categories less favourable as well as unfavourable. Under consideration of the stress level, a high or very high sensitivity regarding utilisation intensification results. Under urban climatic aspects, these areas are in need of rehabilitation, which results in the following planning advice:
- No further aggregation,
- Improvement of ventilation and increase of vegetation,
- Conservation of all open spaces and
- De-sealing and, if necessary, planting of inner courtyards.
Beside the inner city area there are also districts with strongly developed centres, e.g. Spandau, Weißensee or Hohenschönhausen. Furthermore, a low to average local impact may occur in the entire city area and is not limited to the aggregation areas. In isolated cases a bio-climatic impact can occur despite an existing cold air affect range. In such a case the potential impact situation can be so high that even a cold air flow is not able to achieve a significant compensation.
The situation in the peripheral area of Tempelhof is shown in Fig 8. The bio-climatically impacted industrial areas along the S-Bahn tracks are especially visible, in particular in the district of Mariendorf. At the same time, the green-shaped development becomes noticeable as climatically favourable settlement areas (lime green and beige colour).
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Fig. 8: Examples of local bio-climatic burdened areas outside of the inner city, here in the districts Marienfelde/Mariendorf
Ventilation lanes in the districts of Marienfelde/Mariendorf, which in this case introduce cold air from the surrounding countryside, are denoted by the arrow signature. The Freizeitpark Marienfelde, as well as green settlement types act ventilation lanes. Due to the attribution to the aforementioned impact areas, a high urban climatic significance can be assigned to the green spaces and their function as ventilation lanes.
Traffic-related air pollution
The illustration of potential traffic-induced air pollution along main roads and green spaces complements the spectrum of occurring loads (cf. Methodology).Furthermore, the areas within green spaces have been definded, which can show a NO2 concentration of more than 80 µg/m³ at weather conditions with a poor air exchange. A detailed illustration of the screening-results within the road network is given in the map 03.11 "Traffic-related air pollution" (SenStadt 2008a). PIn this context, planning advices are a component of immission- and traffic-related sectoral planning as described e.g. in the clean air plan for Berlin (cf. SenStadt 2008) or the urban development plan (StEP) Verkehr (cf. SenStadt 2002ff).
From the perspective of urban climate, the reference to a preferably low-polluted atmosphere is of particular importance for the preservation and promotion of fresh air. Solely this approach can ensure the preservation and optimization of urban ventilation.
In the Planning Advices Map cold air ventilation lanes and outflows are divided into two categories, whereby the significance rises with growing proximity to the impact areas. Ventilation lanes with a very high significance promote the penetration of cold air into the inner city area and to burdened district centres. Examples are the allotments at the S-Bahnhof Priesterweg, which carry the cold air from the graveyard on Bergstraße as well as from the Insulaner due north or the Volkspark Rehberge, which allows the transport of the cold air produced at the Airport Tegel towards Mitte. Further ventilation lanes of this category are grouped north and south of the S-Bahn-Ring.
Merely the Grunewald has a broad extended cold air outflow with a high significance and at its eastern side a high cold air reach can be assumed. Ventilation lanes with an average to high significance are situated mostly on the periphery of Berlin, which is also true of the spatial cold air outflow in this category. For these prominent structures or processes the following planning advices can be derived:
- Prevention of constructional barriers, which could induce a cold air congestion,
- Keep building heights as low as possible,
- Align new development to stream channels,
- Prevention of peripheral development and
- Conservation of green and open spaces.
The valley sections of the larger rivers Havel and Spree appear as spatial air-stream and ventilation channels, which exceed their local air exchange function. They benefit the air exchange in the bordering development even during strong, superordinated weather conditions. For planning purposes the river banks should be kept free, or at least be lightly developed.