Introduction to the CO-MICC pilot climate service: Supporting risk assessment and adaptation by providing multi-model based information on freshwater-related hazards of climate change for all land areas of the globe

While decision makers in climate-dependent sectors are increasingly considering climate change (CC) in their risk portfolios, there is a structural lack of information on how to assess specific CC-related risks and what to do in practice. The ERA4CS (European Research Area for Climate Services) supported the CO-MICC research project (2017-2021) that aimed to co-develop in a participatory manner with potential end-users how the output of global hydrological models can be optimally used to support climate change risk assessment of freshwater-related hazards at different scales.

In particular, it was investigated how the output of multiple global hydrological models (e.g., groundwater recharge or streamflow), each driven by the output of multiple global climate models, can be best provided in an interactive map-based web service to show the range of plausible future impacts of climate change on freshwater. Data sources are state-of-the-art global future projections following the ISIMIP (Inter-Sectoral Impact Model Intercomparison Project) protocol simulated by the modelling groups of the CO-MICC consortium from PIK, IIASA and Goethe University Frankfurt. In addition, methods for using the relatively coarse information (0.5° by 0.5° grid cells) in regional and local climate change risk assessments were investigated. Through an iterative dialogue process in three rounds of workshops, scientists and end-users learned from each other which particular hydrologic information is valuable for end-user risk assessments - and how to best communicate that information so that it can be practically used by end-users around the world in local, transboundary, and global climate change adaptation and mitigation planning.

The climate service was developed by the CO-MICC consortium and is freely available as a pilot application to all users worldwide at www.co-micc.eu. The web portal of the climate service consists of two components, the knowledge portal and the data portal, respectively. The interactive data portal provides free and easy access to multi-model-based data on future freshwater availability on a global scale. It is a web-based information system that provides access to freshwater-related indicators of climate change hazards for all land areas of the globe except Greenland and Antarctica. The data are visualized and provided for individual 0.5° grid cells or aggregated at the basin or country level. The data viewer contains map display, showing spatio-temporal developments, and a data analysis tool can be used to create statistical and graphical representations of the data. In the knowledge portal, in addition to the introduction to the methodology, online trainings as well as the PUNI (Providing and Utilizing eNsemble Information) handbook are included.

In December 2021, the CO-MICC knowledge and data portal was launched supported by WMO and UNESCO. The pilot climate service is hosted by the UNESCO Center ICWRGC in conjunction with the German Federal Institute of Hydrology. We will demonstrate the capabilities of the interactive web platform and will provide details on the development process.