BayFORKLIM - Bavarian climate research cooperation | Umweltbundesamt

A central element is the development and application of a regional climate model, in which a highly-detailed assessment of the possible climate changes is to be carried out over the entire state of Bavaria, as a starting point for climate impact research. The regional model is embedded in a global model of the Max Planck Institute for Meteorology: The baseline assumption is a "business as usual" scenario with unmodified emission rates of the most important greenhouse gases, resulting in double the atmospheric carbon dioxide (CO2) level by the year 2050.

Global climate projections:
Temperature increase of 1.8°C, air temperature increase for southern Europe 2°C in winter and between 2°C to 3°C in summer, low precipitation increase in winter and slight decrease in summer.

Statements of the regional model:
The climate change in different regions of Bavaria will not be uniform, but in astonishingly differentiated. Increase in summer temperatures by as much as 6 °C (highest difference in Lake Constance region and western Upper Palatinate, less in northern Bavaria). Temperature increase in the winter considerably lower with less than 1°C . Significant increase in precipitation in winter especially in south-western Bavaria (Franconia and the Bavarian Forest can, conversely, expect a decline). Summer precipitation will decline, particularly in south-western Bavaria. Precipitation and temperature changes will lead to changes in the run-off patterns of rivers and streams (increase in the winter, decrease in summer). High UV levels, especially in winter and spring, will continue to occur for several decades.

UV values

The regional and local climate is influenced by the topography and land use, among other things. Particularly in Bavaria, these parameters vary to an exceptional degree, so that this federal state can expect more differentiated climate changes and effects than elsewhere in Germany. According to current knowledge, all the projected changes in climate and climate effects for Bavaria can be classified as non-hazardous with regard to quality and quantity.

The following climate effects are taken into account:

1. Changed precipitation patterns will lead to an increase in winter flood events. By way of contrast, the number and duration of drought periods in the summer will increase.
2. No drastic changes are expected for the forests of the Limestone Alps in future, either.? The rise in temperature will have a shift in the current ceiling of forest communities of between 50 to 100m, which will particularly favour beech stands.? The decline in summer precipitation will increase the proportion of spruces.
3. An increased UV irradiation does not suggest a negative effect on the photosynthetic CO2 assimilation, the biomass production of higher plants, or the crop yield. However, since many plants, despite their great adaptability, respond differently to elevated UV-B levels, shifts in biodiversity cannot be excluded in some ecosystems.
4. For plankton organisms in lake ecosystems, hazards through UV-B irradiation cannot be excluded even under present conditions, particularly in proximity to the water surface. Although these have the necessary repair mechanisms or avoidance strategies to survive higher UV-B doses, even sublethal damages can lead to changes in species composition through a changed population growth. Occasionally, acute hazards can be expected for game fish in shallow breeding ponds filled with clear spring water.

For the population, a dramatic increase in malignant melanomas is already becoming apparent, associated with sunburns in childhood and excessive sunbathing after the age of 30.

Need for action with respect to the effects of UV-B irradiation on humans:?

1. In-depth education of the population on the consequences of continued exposure to sunlight for the development of skin tumours,

2. Common contact substances and new substances must be assessed for their photosensitizing properties in humans,

3. Future research is needed on the use of systemic photoprotective substances

4. Further studies are needed on the effects of photosensitizing and photoprotective substances with regard to the development or avoidance of malignant skin tumours.

The scientific foundations are to be created for the preparation of avoidance and adaptation strategies on a regional level. The following aspects are considered:

1. For a long time now, differences in soil properties and terrain have been taken into account for the cultivation of agricultural crops. Potential changes in the growth conditions can often be compensated by choices of crop variety or technical measures such as irrigation or drainage.

2. A significant increase in UV irradiation can already be clearly demonstrated today, and the level will remain worryingly high for decades, representing a high potential hazard particularly for humans. Here, educational and preventive measures are urgently advised to avoid a further increase in skin cancer.

3. More attention must be paid to the further development of changes to the precipitation and run-off patterns, particularly since, especially in the winter, increasingly hazardous flood events can occur in the Alps, while the already relatively dry regions such as Franconia can expect a further decrease in precipitation and groundwater renewal.? Hydrology trends cannot yet be fully quantified and allow only general (not specific) adaptive responses such as, for example, changes in the planning principles and concepts for water management measures of a structural or non-structural nature (c.f. KLIWA project).

Objectives:
Protection of agricultural and forestry production, reducing the health risks of UV irradiation, avoiding dangerous flood situations, ensuring the water supply.