Impact of a changing climate, land use, and water usage on Europe's water resources : a model simulation study

This report describes an assessment of the projected future impacts of climate change, land use change and changes in water consumption on water resources for the European continent, as obtained using JRC's LISFLOOD water resources model. For this study, two 30-year climate windows were investigated and compared to the 1981-2010 control climate window. A 30-year window (on average 2026-2055) around the year that global warming reaches 2°C at global scale has been analysed, to assess the consequences of climate change if Europe would meet the targets of the Paris climate agreement of December 2015. Depending on the level of emission reductions, the 2 degree global temperature increase limit may be reached already around 2040 when there would be limited mitigation (RCP8.5 scenario) or much later this century - or never - when there would be subtantial mitigation and thus reduced emissions. For a more worst-case situation and its effects, a further window 2070-2099 under an RCP 8.5 emission scenario was investigated as well. This reflects a situation where global temperature increase is already 3.5-4 degrees. We conclude in this report that meeting the objectives of the Paris Climate Agreement of 2015 will lead to substantially less severe impacts for the water resources in Europe as compared to the impacts of climate change beyond 2 degrees global temperature increase. Issues with flooding and especially summer water scarcity are projected to increase. A North-South pattern emerges across Europe for water availability under a 2°C warming scenario. Overall, Southern European countries are projected to face increased water shortages, particularly Spain, Greece, Cyprus, Italy and Turkey. The contribution of land use changes and water demand changes combined are in the order of 10-20%, whereas climate is responsible for 80-90% of the projected changes. The severity of impacts under the 2°C warming scenario suggests that mitigation alone is not enough to avoid adverse climate change impacts; adaptation strategies such as water savings and efficiency measures will be needed too.