Abstract
Abstract. Many recent studies indicate climate change as a phenomenon that significantly alters the water cycle in different regions worldwide, also implying new challenges in water resource management and drought risk assessment. To this end, it is of key importance to ascertain the quality of regional climate models (RCMs), which are commonly used for assessing at proper spatial resolutions future impacts of climate change on hydrological events. In this study, we propose a statistical methodological framework to assess the quality of the EURO-CORDEX RCMs concerning their ability to simulate historic climate (temperature and precipitation, the basic variables that determine meteorological drought). We then specifically focus on drought characteristics (duration, accumulated deficit, intensity, and return period) determined by the theory of runs at seasonal and annual timescales by comparison with high-density and high-quality ground-based observational datasets. In particular, the proposed methodology is applied to the Sicily and Calabria regions (southern Italy), where long historical precipitation and temperature series were recorded by the ground-based monitoring networks operated by the former Regional Hydrographic Offices, whose density is considerably greater than observational gridded datasets available at the European level, such as E-OBS or CRU-TS. Results show that among the more skilful models able to reproduce, overall, precipitation and temperature variability as well as drought characteristics, many are based on the CLM-Community RCM, particularly in combination with the HadGEM2 global circulation model (GCM). Nevertheless, the ranking of the models may slightly change depending on the specific variable analysed as well as the temporal and spatial scale of interest. From this point of view, the proposed methodology highlights the skills and weaknesses of the different configurations and can serve as an aid for selecting the most suitable climate model for assessing climate change impacts on drought processes and the underlying variables.
Highlights
A growing number of scientific studies claims that climate change due to global warming will significantly alter the water 30 cycle, with an increase of the intensity and frequency of extreme hydro-climatic events in several areas around the globe (Arnell et al, 2001; Huntington, 2006; IPCC, 2014; IPCC, 2018)
It is of key importance to ascertain the quality of Regional Climate Models (RCMs), which are commonly used for assessing at 15 proper spatial resolutions future impacts of climate change on hydrological events
The Coordinated Regional Climate Downscaling Experiment (CORDEX) initiative is the first international program providing a common framework to simulate both historical and future climate at the regional level, under different Representative Concentration Pathways (RCPs), and over different domains which cover all the land areas. It provides climate data simulated by an ensemble of RCMs developed by several research centres all over the 55 world which are forced by Global Circulation Models (GCMs) from the Coupled Model Intercomparison Project phase 5 (CMIP5) (Taylor et al, 2012)
Summary
A growing number of scientific studies claims that climate change due to global warming will significantly alter the water 30 cycle, with an increase of the intensity and frequency of extreme hydro-climatic events in several areas around the globe (Arnell et al, 2001; Huntington, 2006; IPCC, 2014; IPCC, 2018). The Coordinated Regional Climate Downscaling Experiment (CORDEX) initiative is the first international program providing a common framework to simulate both historical and future climate at the regional level, under different Representative Concentration Pathways (RCPs) (van Vuuren et al, 2011), and over different domains which cover all the land areas It provides climate data simulated by an ensemble of RCMs developed by several research centres all over the 55 world which are forced by Global Circulation Models (GCMs) from the Coupled Model Intercomparison Project phase 5 (CMIP5) (Taylor et al, 2012). Regardless of the specific methods used to assess the differences between simulated and observed data, one of the main limitations in this approach is that the considered spatial resolution is too coarse for reliable climate change impact studies at relevant hydrological scales, especially in areas of complex topography From this point of view, large-scale observational gridded datasets are of poor applicability, since they are built upon low-density hydro-meteorological networks. Beyond the intercomparison analysis of the EURO-CORDEX RCMs, the present study aims at identifying potential sub-regions where model improvements are advisable
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
