The 2018 European drought under future climate conditions
Abstract
2018 was characterized by an extended period of anomalously dry conditions in central and northern Europe, impacting agriculture, nature, navigation, industry, drinking water supply, daily life. As weather extremes generally do, this drought triggered questions regarding the role of anthropogenic climate change in its occurrence and on what to expect in a warming climate. In the Netherlands it furthermore pushed the assessment of the action perspective during times of drought and of adaptation measures to increase the drought resilience.
In response to these questions, we employ a so-called storyline approach, in which we reconstruct the 2018 drought, but set in a 1.5°C, 2°C and 3°C warmer world, and assess the possible implications of global warming for the evolution of a 2018-like drought. We run the regional climate model KNMI RACMO2 over Europe with initial conditions and lateral boundary conditions from ERA5 for the year 2018. Subsequently, we apply perturbations to the sea surface temperature, initial land surface temperature, greenhouse gas and aerosol forcing and to the lateral boundaries, representing modifications for future climate conditions. In its simplest form the atmospheric perturbations represent a uniform warming with constant relative humidity - known as pseudo- or surrogate global warming experiments. Here we additionally use the 16-member initial-condition ensemble generated with the global climate model EC-EARTH v2.3 to derive more plausible perturbations, consistent with the evolution of the atmospheric circulation in 2018. On the one hand this approach allows us to investigate mechanisms of future changes in droughts conditional on a specific realization of atmospheric circulation. On the other hand it provides physically plausible scenarios for future droughts that, since they are based on an actual recent event, decision and policy makers can relate to, and - provided that they are framed correctly - can be used in stress tests and in the assessment of adaptation strategies.- Publication:
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AGU Fall Meeting Abstracts
- Pub Date:
- December 2019
- Bibcode:
- 2019AGUFM.H12F..06A
- Keywords:
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- 1812 Drought;
- HYDROLOGY;
- 1817 Extreme events;
- HYDROLOGY;
- 1847 Modeling;
- HYDROLOGY;
- 1880 Water management;
- HYDROLOGY