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Heavy precipitation is a major hazard over Europe. It is well established that climate model projections indicate a tendency toward more extreme daily rainfall events. It is still uncertain, however, how this changing intensity translates at the subdaily time scales. The main goal of the present study is to examine possible differences in projected changes in intense precipitation events over Europe at the daily and subdaily (3-hourly) time scales using a state-of-the-science climate model. The focus will be on one representative concentration pathway (RCP8.5), considered as illustrative of a high rate of increase in greenhouse gas concentrations over this century. There are statistically significant differences in intense precipitation projections (up to 40%) when comparing the results at the daily and subdaily time scales. Over northeastern Europe, projected precipitation intensification at the 3-hourly scale is lower than at the daily scale. On the other hand, Spain and the western seaboard exhibit an opposite behavior, with stronger intensification at the 3-hourly scale rather than the daily scale. While the mean properties of the precipitation distributions are independent of the analyzed frequency, projected precipitation intensification exhibits regional differences. This finding has implications for the extrapolation of impacts of intense precipitation events, given the daily time scale at which the analyses are usually performed. [ABSTRACT FROM AUTHOR]

Surface air Temperature variations (DT) on the short time scale (from 1 to 7/15/30 days), defined as the difference of daily temperature between one day and a next one, can have strong impacts on human health and plant development. This analysis investigates EURO-CORDEX Regional Climate Model simulations data, at the highest horizontal resolution available (EUR-11 domain: about 11 km) collected within the EU H2020 project COACCH. The Mediterranean regions appears as the most prone to DT increase, in a warmer climate, within the European domain. Based on a multi-model multi-scenario approach we aim to quantify such changes and the related uncertainty within the current century. Changes in the length of the seasons are also inspected to verify potential linkages to the DT changes. The model validation is based on JRA-55 reanalysis covering the 1985-2015 period. Future tendencies of the aforementioned parameter are inspected following three Representative Concentration Pathways (RCPs) taking part to the fifth Coupled Model Intercomparison Project (CMIP5): RCP2.6, RCP4.5 and RCP8.5. A comparison of the results obtained based on bias corrected and raw temperature data is provided and discussed.The Keywords: Temperature, Europe, Future Scenarios, CORDEX [ABSTRACT FROM AUTHOR]

Global climate models (GCMs) have been used extensively as a tool to investigate future changes in heavy precipitation. However, their spatial resolution is generally too coarse for their application for decision making and for impact studies at a more local scale. To mitigate these issues, dynamical downscaling of heavy precipitation using regional climate models (RCMs) can provide information at a spatial resolution that makes their outputs locally useful. Although many studies highlighted the improvements by RCMs in reproducing the precipitation processes, much less is known about their capability in reproducing the temporal clustering of heavy precipitation. Here we use Cox regression to investigate temporal clustering in heavy precipitation driven by four dominant large-scale climate modes (Arctic Oscillation, North Atlantic Oscillation, East-Atlantic Pattern, and Scandinavia Pattern) over Europe. Results are based on high-resolution RCMs (i.e., 0.11° and 0.44°) part of the Coordinated Downscaling Experiment-European Domain (EURO-CORDEX) and use observed daily precipitation from the E-OBS as reference data. In addition to analyses at the continental scale, we consider the added value of these simulations at a regional scale. We find that RCMs are skillful at capturing the observed temporal clustering of heavy precipitation events across Europe. Moreover, the 0.11°-RCMs did not perform better than their 0.44°-version; these findings can potentially suggest that the current configuration of these models has reached an upper limit of performance in reproducing the temporal clustering, and finer resolution and modeling may be necessary to increase the realism in reproducing the processes at play. • RCMs are skillful at capturing the observed temporal clustering of heavy precipitation. • The 0.11°-RCMs did not perform better than their 0.44°-version. • At the sub-regional scale, there was more variability among the different models. [ABSTRACT FROM AUTHOR]