Klimaatverandering en wateromleiding risico voor ecologie van de Maas

Verminderde waterafvoer in de Maas kan de kwetsbare ecologie van de rivier negatief beïnvloeden. In de toekomst speelt klimaatverandering daarbij een belangrijke rol en in beperkte mate mogelijk ook de wateromleiding van de Roer

Ein GIS-basiertes Planungstool zur Unterstützung von Kommunen in ihrer Anpassung an Starkniederschläge

Human-caused climate change is intensifying the frequency and intensity of heavy rain events. Heavy rains are generally understood as precipitation events with a high amount of rainfall. These events usually occur locally. Due to their high intensity, they can lead to flash floods, floods, erosion and overloading of the sewer network. Although climate change adaptation and adaptation to heavy rain events have become integral items of the climate policy agenda over the last decade, they still pose major challenges for German municipalities. In this thesis, the key challenges hindering municipalities when planning and implementing measures to adapt to heavy rain events are investigated and a novel tool to mitigate these challenges is proposed. The status quo in municipalities and the challenges they face were established using a survey, detailed one-on-one interviews and extensive literature research. On the basis of the results obtained, the hypothesis is formulated that municipal adaptation planning can be improved by instruments that support interdisciplinary communication, capacity building and/or decision-making. A GIS-based planning tool is developed to help planners assess the need for action as well as to determine the adaptation potential of municipalities. The latter includes their capabilities to formulate conceptual plans, which can be used to support decision-making in the adaptation and planning process on the appropriate protective measures to implement. The hypothesis and usefulness of the planning tool were verified in a target group workshop. The overriding root cause of many of the challenges can be found in the lack of legislative requirements or institutional agreements. Specifically, there are challenges posed by existing or non-existing legal bases, coordination mechanisms within and between sectors, unclear roles and responsibilities and differences in planning cultures. These make it difficult to assess the need for action and reach consensus on the cost and effectiveness of individual measures. Uncertainties in climate change projections complicate finding agreement on adaptation strategies, putting existing risk management approaches to the test. Furthermore, climate change adaptation strategies necessarily involve a wide range of stakeholders with different interests and understanding of the issues. These uncertainties affect municipal planning practice. At the municipal level, the main obstacles can be localised in the initial planning phase, the identification of the need for action and the adaptation potential as well as developing options and their assessment. The rather restrained strategy development and implementation to date is attributed, among other things, to scarce financial and human resources, institutional obstacles. Moreover, not only an assessment of cost and effectiveness of protective measures is needed but also instruments and tools to support decision-making processes. Through capacity development, targeted approaches to communication and awareness raising, the creation of a common adaptation culture is achieved. It is important that the different disciplines involved (e.g. water managers & municipal planning) learn from each other in order to build and expand each other's awareness and capacities with regard to climate change adaptation. Tools, methods, technologies and practices can be used to support collaboration and explicit intra-municipal communication. Thereby, synergies are exploited and obstacles and restrictions are recognized early on and can be jointly eliminated. The GIS planning tool developed in this thesis encourages communication and collaboration between planning experts. It is suitable for determining the municipal’s adaptation potentials as well as the need for action during heavy rain events. As such, it contributes to finding a common consensus in issues related to adaptation to heavy rain events

Effects of water diversion and climate change on the Rur and Meuse in low-flow situations

Water scarcity is one of the problems in water management that hinders European rivers in reaching a good ecological status as defined in the European Water Framework Directive. Water scarcity often coincides with high water temperature and low water quality. High water temperatures decrease the oxygen supply and often coincide with low flows that tend to increase the load of various compounds that affect the equilibrium in the ecosystem. The river Meuse regularly encounters situations of low water flow. In these situations, the river Rur, an important tributary of the river Meuse in Germany, contributes significantly to the Meuse discharge. Climate change can lead to more frequent periods of water scarcity. Moreover, plans exist to divert water from the Rur to former brown coal quarries in Germany. This exploratory study examines the relationships between discharge, water temperature and water quality under future climate change and water diversion scenarios in low-flow situations for the rivers Meuse and Rur. The results of the study confirm that rising air temperatures as a result of climate change will lead to higher water temperatures which will negatively impact the water quality of the Meuse in particular. Despite the fact that the contribution of the Rur has a positive impact on the water quality of the Meuse, the results suggest that effects of plans to divert water from the Rur may be small on average. However, the impact of the diversion may be stronger on individual hot summer days with low water levels when the Rur contributes significantly to the discharge of the Meuse.</p

The AWESOME Project: A decision analytic framework for managing Water Energy Food and Ecosystems across sectors and scales in the South Mediterranean

Rapid population growth and rising economic prosperity are imperatively challenging the South Mediterranean and the African North-East to a point where they may compromise the sustainable use of natural resources. In those regions, the demand for water, energy, food, and the preservation of ecosystems are expected to increase relevantly. Transboundary rivers like the Nile River Basin represent an enormous source of water, energy, food, and ecosystems (WEFE), which often brings conflicts and individualistic policies among the sharing countries. The adoption of integrated and participatory approaches that explicitly account for the WEFE Nexus are necessary to explore multisectoral synergies and tradeoffs and to generate shared economic, environmental, and societal benefits. Focused on the Nile River Basin and born in this context, we present here the AWESOME project (i.e. mAnaging Water, Ecosystems and food across sectors and Scales in the sOuth Mediterranean), whose main objective is developing a decision-analytic framework based on a multi-level, integrated WEFE model to address the Nexus and explore the interdependencies and feedbacks across a hierarchy of spatial scales, from the macroeconomic development (macro), to regional planning (meso), down to the single farm (local). At the local scale, a demo-site of smart agricultural solutions (soilless agriculture, e.g., hydroponics, aquaponics) is currently under construction, and it will provide indicators on effectiveness and sustainability of these new technologies to back up existing systems in a dryer future. The study on site will also demonstrate the performance of such a technology within its local economy and ecosystem. At the meso scale, we are developing a decision-analytic framework covering the course of the Nile River Basin, from the Grand Renaissance Dam (GERD) in Ethiopia up to the Nile Delta, based on hydrological models and combined with the results of systems analysis methods with advanced a-posteriori multi-objective optimization algorithms. We plan to simulate existing water availability, water distributions system and new agricultural technologies, upscaling the local scale assessments while downscaling the climate, energy, crop, and ecosystems projections at the macro scale. This approach allows the design of a set of efficient solutions and associated performance with respect to the WEFE multidimensional assessment space, where stakeholders and policy makers will be able to explore multisectoral tradeoffs and negotiate potential compromise alternatives. We expect that AWESOME will make substantial progress in complex systems analysis to support the transition towards a more sustainable and resilient agriculture along the Nile River Basin under diverging water availability and demand due to the projected impacts of changing climate and society