Climate and discharge projections (RheinBlick2050)

The overall goal of the RheinBlick2050 project is the development of joint climate and discharge projections for the international Rhine River catchments. This website is intended to give a brief overview on the most relevant aspects of the project; for further information please contact the coordinator Klaus Görgen (goergen [at] lippmann [dot] lu).

Background and goals

Linked to climate change is an increase of the climate system's variability which is accompaignied by changes in the frequency and intensity of meteorological extreme events. Global climate change projections indicate robust large-scale changes of the precipitation regime (e.g. decrease of summer-, increase of winter precipitation in Central Europe) (e.g. IPCC, 4AR WG1, 2007). Linked to this are modifications of discharge (low flow and high flow conditions) and hydraulic regimes, with variable impacts on managed (anthropogenic) and unmanaged (natural) systems, depending on their sensitivity and vulnerability (ecology, economy, infrastructure, transport, energy production, water management, etc.). Even under an efficient climate change mitigation policy, climate change is going to have primarily negative impacts in the upcoming years. In this context, decision makers need adequate adaptation and mitigation strategies to minimize adverse effects of climate change. An improved knowledge on the potential impacts including uncertainties means an extension of the informed options open to these end users of our research.

In this context the main goals of the project are the development of joint, consistent climate and discharge projections for the international Rhine River catchments. This helps in the assessment of future changes of hydro-meteorological regimes in the Rhine River catchments and how such impacts influence hydrologic and hydraulic processes (i.e. an improved understanding of the physical system change). Based on the respective datasets, a derivation of applicable information and results for the policy and planning relevant time-span until 2050 (overall until 2100) is possible. The focus is on meso- to macro-scale catchments. Potential users of the findings and data, stakeholders and decision makers are involved: the project plan can be adjusted, in terms e.g. of the analysis to be done, in order to meet their requirements ("bottom-up" approach, they define the ultimate science question by their demand for specific information). A synchronisation and collaboration with existing projects and initiatives is therefore a prerequisite of the project.

Deliverables

• A common reference hydro-meteorological observational data set is to be generated.
• A hydrological model forcing data set based on a set of ensembles of regional climate change projections for various climate change scenarios.
• Simulations of hydrological models.
• The final results will be usable information and quantifiable statements (e.g. extreme value statistics, uncertainty assessments, validation) that might form the basis for further planning or policy relevant decisions by incorporating the potential users of the data and results.
• All results will be summarised in a technical report.

Organisation

• RheinBlick2050 uses a data-synthesis, multi-model approach; simulations of transient regional climate change projections are used as forcings for existing calibrated hydrological and hydraulic models after extensive validations and bias corrections of the forcing data have been done, based on a hydro-meteorological reference dataset.
• As many projects in this area already exist - albeit with no consistent datasets or synchronized strategy -, RheinBlick2050 is basically designed as a "meta" project, i.e. it tries to use, aggregate and summarize existing / ongoing project's results, data, methods, tools and models, thereby limiting the amount of redundant work.
• RheinBlick2050 is an international project where research institutions, universities, public institutions and national (weather) services collaborate. To get the required feedback from end-users and various stakeholders, the project is for example in contact with the ICPR and respective representatives and institutions of the German federal states.
• To further disseminte information, there will be two official workshops during the project on the regionalized climate change projection datasets as drivers for the hydrological models and finally the hydrological modelling results and the associated analyses themselves.
• The spatial focus is on the complete Rhine River catchment, whereas simulations and analyses are done for meso-scale sub-catchments therein.
• A special emphasis is on extreme events (low- and high-flow conditions) which makes it necessary to use regional data.
• The overall project runtime is scheduled for 2 years from February 2008 to January 2010.

Methodologies and data, workpackages

• End user requirements (further refinement throughout the project) are defined; overview on existing projects, datasets, methodologies is to be generated.
• Compilation of a hydro-meteorological reference dataset based on observations from national weather services and other sources from 1961 to 2005 for Central Europe; variables (where available): total precipitation, 2 m humidity, sunshine duration, 2 m air temperature, 10 m wind speed; daily temporal resolution; two datasets: timeseries for station locations and gridded interpolated data at 5 km spatial resolution.
• Existing regional climate change projections (e.g. from the REMO model, KNMI downscaling projects, the FP6 Ensembles project) have to be bias corrected before they can be used as inputs to hydrological model simulations. Different bias correction methodologies are to be tested for selected meso-scale catchments in advance.
• Hydrological model runs with existing calibrated hydrological models will deliver the discharge projections that will enter the analyses (e.g. extreme value statistics) and might serve as inputs to investigations on the impacts of the changed river discharge regimes and to adaptation studies.

Project group

The core project group is made up of members from the following institutions.

France
Cemagref, Hydrosystems Research Unit / Hydrology Group, Antony

Germany
Federal Institute of Hydrology, Koblenz

Luxembourg
Public Research Centre - Gabriel Lippmann, Department of Environment and Agro-Biotechnologies (EVA), Belvaux

Switzerland
Federal Office for the Environment, Hydrology Division, Bern

The Netherlands
Rijkswaterstaat - Centre for Water Management, Lelystad

Latest update: 2008-03-16 by GOERGEN [at] LIPPMANN [dot] LU.