REKLISO - Regional Climate Analysis of the Southern Upper Rhine | Umweltbundesamt

The forecasting and evaluation of the most important climatological parameters will be prepared in cooperation with other projects in the region (KLIWA and KLARA).

Depending on the underlying emission scenario a mean global temperature rise of between 1.4 and 5.8°C by the year 2100, compared with the period from 1961 to 1990, will be assumed (according to IPCC 2001). For Baden-Württemberg and the scenario period up to about 2050, the following regional climate developments can be expected: increase in average temperatures, changes in temperature extremes, changes in precipitation, changes in river run-off and increased groundwater recharge. In addition, heat island effects will increasingly influence the local climate in urban areas.

wind speed, snow cover, air pollutant concentrations, bioclimatic parameters (the thermal effect complex, or heat stress and cold stress, and the air-hygienic effect complex, or air pollution at ground level).

2050

The expected climate changes in Baden-Württemberg will have the following significant effects on people, biodiversity and ecosystems as well as land use in the coming decades:

• An increase in extreme events (floods, storms) will lead to greater immediate life and health risks for the population. In addition, an increase in the extent of property damages is to be expected.
• A projected increasing frequency and intensity of summer heat waves and of the number of hot days will present a growing health risk. The parallel decline of cold stress expected in winters will not be able to compensate for the increasing exposure to heat stress.
• Overall climate warming will have significant effects on native animal and plant species, their population size and on natural ecosystems.
• Climate change will have positive as well as negative effects on agriculture: In general, the requirements for maize cultivation (grain maize in particular) in the Upper Rhine region will be improved by climate warming, while a tendency towards increasing drought stress in summers will lead to local losses in crop yields.
• Less serious changes in productivity are expected for the forestry sector since little change in the annual precipitation total is projected so far. However, an increase in the damages through pests and extreme weather events is expected.
• Climate change is expected to produce more positive effects for summer tourism in Baden-Württemberg while having negative effects on winter tourism.

These impacts of climate change in Southwest Germany will also have a considerable effect on the spatial development of the Southern Upper Rhine region. The following two threats are particularly significant for spatial planning in the region:

• Flooding risks will increase significantly, particularly in winter.
• Summer heat stress in valleys and lowland areas, which is already high today, will increase considerably, particularly in settlement areas.

Due to the expected high heat stress and sharp increase in heavy rain and flood risks, the Upper Rhine region is one of the regions threatened most by climate change in Germany.

The results show that the population’s vulnerability in the state of Baden-Württemberg will increase by a factor of approximately 20% through heat stress. According to the scenario analyses, an additional 180 to 400 heat-related deaths per year can be expected. The vulnerability through heat stress is determined by the frequency of heat events, as well as the population-specific sensitivity. However, the health sector’s adaptive capacity is not considered here.

In addition to climate mitigation, the adaptation to unavoidable climate impacts is essential. This particularly includes summer heat stress in the Upper Rhine region, which is already above average today.

Spatial planning plays a vital role for the preservation of favourable climatic conditions in the Southern Upper Rhine region: It is necessary to ensure that the effects of global climate change are not aggravated locally, but rather mitigated as much as possible by maintaining the open spaces necessary for a balanced climate, as well as implementing an adapted urban development and design strategy. The paramount task of spatial planning in the Southern Upper Rhine region in the future will be to secure climatically and air-hygienically favourable living and working conditions for the local population.

A central aim of adaptation is the integration of climatic surface functions in spatial planning. To this end, the relevant results are made available in the form of climate analysis and planning guide maps that can be used for spatial planning. The development of specific objectives and recommendations for action for spatial planning from a climatological perspective will be carried out for the topics of ventilation, air hygiene and thermal situation. First and foremost, the results provide a basis for updating the landscape framework plan and the regional plan for the Southern Upper Rhine. Second, they will have a signal effect for urban planning, building development, landscape design, technical planning and relevant, isolated spatial planning projects at the local level.