Keywords
urban growth scenarios, urban patterns, urban sprawl, climate change, urban heat island
Start Date
1-7-2012 12:00 AM
Abstract
The objective of this paper is to assess the influence of future urbangrowth scenarios on future urban climate in Toulouse metropolitan area (France).Specifically, we aim to test the hypothesis that urban growth based on sprawlingpatterns has a greater influence on the Urban Heat Island (UHI) phenomena thancompact patterns. Three urban growth scenarios are built by 2100 followingdifferent urban patterns (edge growth, spontaneous growth and a hybrid of both).Those simulations are performed using a new spatially explicit urban growth model(SLEUTHR) which was specifically developed for that purpose. The impact of urbangrowth on the air temperature is estimated under the same climate conditions usingthe atmospheric Meso-NH model. The influence of urban form on urbanmicroclimate is assessed by comparing the UHI map of 2006 with the UHI mapsexpected by 2100 with respect to the urban expansion scenarios. Simulations withMeso-NH show that, for the 2006 experience, the center of Toulouse is warmerthan the surrounding rural areas by about 6.4 °C at both 00 LT and 06 LT. Theresults highlight an increase of 1 to 2 °C in the u rban air temperature at thebeginning of the night and a lost of cool capacity in the scenarios. Furthermore, theresults indicate that big differences in the scenarios are found when exploring thehorizontal distribution of the UHI. The increase in the urbanized surface by 2100leads to a general elevation of temperatures of about 1 °C at both 00 LT and 06 LT.
Assessing the influence of long-term urban growth scenarios on urban climate
The objective of this paper is to assess the influence of future urbangrowth scenarios on future urban climate in Toulouse metropolitan area (France).Specifically, we aim to test the hypothesis that urban growth based on sprawlingpatterns has a greater influence on the Urban Heat Island (UHI) phenomena thancompact patterns. Three urban growth scenarios are built by 2100 followingdifferent urban patterns (edge growth, spontaneous growth and a hybrid of both).Those simulations are performed using a new spatially explicit urban growth model(SLEUTHR) which was specifically developed for that purpose. The impact of urbangrowth on the air temperature is estimated under the same climate conditions usingthe atmospheric Meso-NH model. The influence of urban form on urbanmicroclimate is assessed by comparing the UHI map of 2006 with the UHI mapsexpected by 2100 with respect to the urban expansion scenarios. Simulations withMeso-NH show that, for the 2006 experience, the center of Toulouse is warmerthan the surrounding rural areas by about 6.4 °C at both 00 LT and 06 LT. Theresults highlight an increase of 1 to 2 °C in the u rban air temperature at thebeginning of the night and a lost of cool capacity in the scenarios. Furthermore, theresults indicate that big differences in the scenarios are found when exploring thehorizontal distribution of the UHI. The increase in the urbanized surface by 2100leads to a general elevation of temperatures of about 1 °C at both 00 LT and 06 LT.
