Showing papers by "Zbigniew W. Kundzewicz published in 2011"

The use of scenarios as the basis for combined assessment of climate change mitigation and adaptation

Abstract: Scenarios are used to explore the consequences of different adaptation and mitigation strategies under uncertainty. In this paper, two scenarios are used to explore developments with (1) no mitigation leading to an increase of global mean temperature of 4 °C by 2100 and (2) an ambitious mitigation strategy leading to 2 °C increase by 2100. For the second scenario, uncertainties in the climate system imply that a global mean temperature increase of 3 °C or more cannot be ruled out. Our analysis shows that, in many cases, adaptation and mitigation are not trade-offs but supplements. For example, the number of people exposed to increased water resource stress due to climate change can be substantially reduced in the mitigation scenario, but adaptation will still be required for the remaining large numbers of people exposed to increased stress. Another example is sea level rise, for which, from a global and purely monetary perspective, adaptation (up to 2100) seems more effective than mitigation. From the perspective of poorer and small island countries, however, stringent mitigation is necessary to keep risks at manageable levels. For agriculture, only a scenario based on a combination of adaptation and mitigation is able to avoid serious climate change impacts.

Model-Supported Impact Assessment for the Water Sector in Central Germany Under Climate Change—A Case Study

Abstract: Climate change challenges water managers and researchers to find sustainable management solutions, in order to avoid undesirable impacts on water resources, environment and water-dependent sectors. Needed are projections into the future for the main driving forces, the resulting pressures on water resources, and quantification of the impacts. Modeling studies can play an important role in investigating, quantifying, and communicating possible impacts of climate change, with account of uncertainty of the results. However, climate change related impacts and a need for adaptation still play a minor role in current river basin management plans that have to comply e.g. with the EU Water Framework Directive (WFD). One important reason is that climate impact assessment is generally done in research institutes, while management plans are designed by practitioners working in national and regional environmental agencies and water supply companies. Knowledge transfer from science to practice and visa versa is often missing. In the present study, we propose a methodology and a case study for model-supported decision making in the water sector applicable to a participatory water resources planning process. The methodology is applied in a case study investigating climate change impacts on water resources. The case study area is the German State of Saxony-Anhalt, where the task was to develop a climate change impact assessment including possible adaptation measures as basis for a federal adaptation directive.

Water-related conflicts in urban areas in Poland

Abstract: Water-related conflicts in urban areas have a long history. Recently, the rapidly growing portion of the global population living in urban areas outnumbered the rural population, with consequences in the massive concentration of freshwater demands and of wastewater generation, lumped over land areas covered by the urban fabric. Water-related conflicts in urban areas may come about in relation to three categories of water problem: having too little water, too much water, or seriously polluted water. Conflict, controversies and tensions over water occur between urban and rural populations, between upstream and downstream riparians, and between different water uses (such as agricultural irrigation, municipal demands, industry and energy production). This study reviews the characteristics and mechanisms of water-related conflicts in urban areas in Poland. Diffuse water pollution in upstream land areas influences water quality (and water treatment) in downstream urban areas. In contrast, point-source ...

Intense Precipitation and High Floods - Observations and Projections

Abstract: According to physical laws, the water-holding capacity of the atmosphere and hence the potential for intense precipitation increases with warming. Since a robust warming signal and a number of large rain-caused floods have been observed recently, it is of paramount importance to examine whether there has been an increasing trend in intense precipitation and flood flow. However, even if widespread increases in observed intense precipitation have been reported in many areas, the analysis of annual maximum river flow records does not detect an ubiquitous and coherent increasing trend. This is in disagreement with some projections for the future, where increasing intense precipitation and flood hazard are expected. One can conclude that flood process is complex, influenced by several non-climatic factors, and can be caused by several generating mechanisms, which are affected in different ways by climate change. Hence, issuing a flat-rate statement on change in flood hazard is not justified.