DATE2022-05-30 13:02:16
TITLEValidation of cold season extremes in Greece
AUTHORSIason Markantonis (1,2) ,Diamando Vlachogiannis (1) ,Athanasios Sfetsos (1) ,Ioannis Kioutsioukis (2)
  1. 1) Environmental Research Laboratory (erel), National Centre Of Scientific Research "demokritos" (ncsrd), Aghia Paraskevi (Greece) ,2) Laboratory Of Atmospheric Physics, Department Of Physics, University Of Patras, Patras (Greece)
ABSTRACTIn this study we conduct a validation of simulation data on extreme events from reanalysis (ERA5, WRF ERA-INTERIM) and EUROCORDEX models (ALADIN63/CNRM, KNMI/EC-EARTH, CLMcom/HadGEM2, SMHI/MPI, DMI/NCC-NorESM1-M) as well as downscaled data by WRF EC-EARTH-GCM, using observations provided by the Hellenic National Meteorological Service (HNMS) from 21 stations in Greece. These models are validated upon extreme cold or wet events for the cold season between October and March of the period of 1980-2004. We apply two different methods of characterizing extreme values, using (a) fixed thresholds such as cold events under 0 °C for daily minimum (TN) or daily maximum temperature (TX) and events over 20mm for daily accumulated precipitation (RR), and (b) percentile thresholds concerning the distribution of the data. In the latter case, we examine events where TN or TX is lower than the 5th percentile or RR is higher than the 95th percentile of the corresponding distribution. The validation is held also for the return levels calculated for 20, 50 and 100 years for these variables. In general, the results by both methods reveal that temperature extremes are simulated comparably well by the majority of models, while precipitation extremes are underestimated not only by the projection models but also by the reanalysis simulations.