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ranges leads to a frequent development of local wind systems, especially at the
slopes and in the valleys. In addition, over large green areas in the surrounding and
the city area especially at the higher altitudes, in the nighttime cold air is produced,
that generates cold air streams. Even if these winds have no high wind speeds, they
play a signifi cant role for the ventilation and local fresh or cold air supply in some
city districts. Preserving these local winds and streams is an important objective in
the urban planning process in Stuttgart with focus on environmental and urban
climate protection since decades. It becomes apparent that primarily cold air fl ows
effectively reduce UHI caused thermal stress in nighttime.
10.1.2 UHI in Stuttgart
The lack of adequate air exchange in combination with high building density and a
huge amount of sealed surfaces, especially in most populated and industrial city
districts, facilitate the development of an intensive UHI. Quantifying the intensity of
Fig. 10.2 Land use map of Stuttgart
R. Rinke et al.