An interactive map, developed at Goethe University Frankfurt in Germany, shows how water resources, groundwater recharge, and evapotranspiration might change in a specific region under different future climate scenarios.

Climate change is altering water availability across the globe, and right on our doorsteps. The Explorer for Climate Change Impacts on Water Resources tool visualises science-based hydrological simulations of future water availability under the influence of climate change.

“Water is one of the key resources of our future, says Professor Petra Döll. "With the Explorer, we are providing society with a tool to prepare for changes early and knowledge-based.”

Developed in cooperation with French geodata specialist AGEOCE, the application shows, with a spatial resolution of approximately 50km, how groundwater recharge could change in different regions across the Earth. This includes assessments of water availability and the extent of rises in evapotranspiration due to the changing climate.

Users can select a specific region on the world map and receive a clear diagram showing projected changes between the reference period 1985 to 2014 and three future time periods. It is particularly helpful that the Explorer shows not only mean values, but also the range of possible developments – depending on the emissions scenario and model uncertainties.

This allows for less favourable developments to be considered and better incorporated into local planning.

Additionally, the Explorer can indicate how many of the models exceed certain thresholds – for example, a decrease in groundwater recharge by more than 20 percent. This helps assess how robust certain developments are and whether there is broad agreement among the models.

“Our application is based on simulation results from an international multi-model ensemble that makes climate impacts comparable across different levels”, explains Dr Fabian Kneier, research associate in the hydrology working group for the Explorer.

“We account not only for uncertainties in the climate projections but also in the hydrological models. This was only made possible through close collaboration between science and practice – across disciplinary boundaries.”

Multiple uses

The web application can be used in water management, environmental planning, policy-making and research and education.

“Our platform makes it possible to present complex multi-model results in an accessible way – for research, policy, and practice worldwide”, says Dr Guillaume Attard, chief executive of AGEOCE.

For instance, say the researchers, in the Rhine-Main region, the tool can help explore whether groundwater recharge is likely to decrease in the coming decades – an important piece of information for cities like Frankfurt, which source a large part of their drinking water from surrounding areas. The application supports the understanding of regional developments and helps to discuss appropriate adaptation measures at an early stage.