Multiscale performance of the ALARO-0 model for simulating extreme summer precipitation climatology in Belgium

Transcription

1 Multiscale performance of the ALARO-0 model for simulating extreme summer precipitation climatology in Belgium Rozemien De Troch 1,2, Rafiq Hamdi 1, Hans Van de Vyver 1, Jean-François Geleyn 2,3, Piet Termonia 1,2 1 Royal Meteorological Institute of Belgium; 2 Department of Physics and Astronomy, Ghent University, Ghent, Belgium; 3 Czech Hydrometeorological Institute, Prague, Czech Republic COST Action WG1+2 Meeting on Parameterization and Downscaling January 29-30, 2014, Milan R. De Troch (RMIB) Multiscale performance of ALARO-0 COST WG / 13

2 1 Introduction 2 Experimental Design 3 Results 4 Conclusion R. De Troch (RMIB) Multiscale performance of ALARO-0 COST WG / 13

3 Models ARPEGE-IFS GLOBAL ALADIN LIMITED AREA MODEL (LAM) + New physics parameterizations centered around improved convection and cloud scheme (Gerard and Geleyn, 2005; Gerard et al., 2009) = 3MT ALARO-0 MESOSCALE AND CONVECTIVE SCALE = GREY- ZONE SCALES R. De Troch (RMIB) Multiscale performance of ALARO-0 COST WG / 13

4 Context 8 km 4 km Radar (obs.) 2 km 1 km 1 km (no 3MT) R. De Troch (RMIB) Multiscale performance of ALARO-0 COST WG / 13

5 Goal Explore the relative importance of resolution versus parameterization formulation on the model skill to simulate realistic extreme daily precipitation R. De Troch (RMIB) Multiscale performance of ALARO-0 COST WG / 13

6 Experimental Design GLOBAL REANALYSIS DRIVING LAM HIGH RESOLUTION LAM ERA-40 reanalysis DYNAMICAL DOWNSCALING ALARO-0 40 km ONE-WAY NESTING ALARO-0 10 km ALARO-0 4 km ALADIN 40 km ALADIN 10 km ENSEMBLES ALADIN-Climate CNRM 25 km Station Observations R. De Troch (RMIB) Multiscale performance of ALARO-0 COST WG / 13

7 Experimental Design DRIVING (i) What is the effect of dynamical LAM downscaling ERA-40 using ALARO-0? GLOBAL REANALYSIS ERA-40 reanalysis DYNAMICAL DOWNSCALING ALARO-0 40 km ALADIN 40 km ONE-WAY NESTING HIGH RESOLUTION LAM ALARO-0 10 km ALARO-0 4 km ALADIN 10 km ENSEMBLES ALADIN-Climate CNRM 25 km Station Observations R. De Troch (RMIB) Multiscale performance of ALARO-0 COST WG / 13

8 Experimental Design GLOBAL REANALYSIS DRIVING LAM HIGH RESOLUTION LAM ERA-40 reanalysis DYNAMICAL DOWNSCALING ALARO-0 40 km ONE-WAY NESTING ALARO-0 10 km ALARO-0 4 km ALADIN 40 km ALADIN 10 km ENSEMBLES ALADIN-Climate CNRM 25 km (ii) Does ALARO-0 give an improvement Station to Observations ALADIN at varying horizontal resolutions? R. De Troch (RMIB) Multiscale performance of ALARO-0 COST WG / 13

9 Experimental Design GLOBAL REANALYSIS DRIVING LAM HIGH RESOLUTION LAM ERA-40 reanalysis ALARO-0 40 km ALADIN 40 km ALARO-0 10 km (iii) How does ALARO-0 perform within DYNAMICAL ALARO-0 the 4 km DOWNSCALING context of state-of-the-art regional ONE-WAY climate NESTING modelling? ALADIN 10 km ENSEMBLES ALADIN-Climate CNRM 25 km Station Observations R. De Troch (RMIB) Multiscale performance of ALARO-0 COST WG / 13

10 Observations m R. De Troch (RMIB) Multiscale performance of ALARO-0 COST WG / 13

11 (i) Effect of downscaling ERA-40 Relative frequency (log) 1e+02 OBS q0.95 OBS ERA40 PSS: 0.76 PSS<q0.95: e+00 PSS>q0.95: 0.62 ALARO 0 (40km) PSS: 0.85 PSS<q0.95: 0.95 PSS>q0.95: e 02 ALADIN (40km) PSS: 0.80 PSS<q0.95: 0.86 PSS>q0.95: e 04 1e Precipitation (mm/day) R. De Troch (RMIB) Multiscale performance of ALARO-0 COST WG / 13

12 (ii+iii) Improvement of ALARO-0 OBS ALARO CNRM 40 km OBS, Summer = mm mm 25 km 10 km 4 km ALR40, Summer = mm ALADIN mm ALR10, Summer = mm mm ALR04, Summer = mm mm ALD40, Summer = mm mm CNRM, Summer = ALD10, Summer = mm mm R. De Troch (RMIB) Multiscale performance of ALARO-0 COST WG /

13 (ii+iii) Improvement of ALARO-0 Relative frequency (log) 1e+02 1e+00 1e 02 1e 04 1e 06 1e+02 1e+00 1e 02 1e 04 1e 06 1e+02 1e+00 1e 02 OBS q0.95 OBS ALARO 0 (40km) PSS: 0.85 PSS<q0.95: 0.95 PSS>q0.95: OBS q0.95 OBS ALARO 0 (10km) PSS: 0.86 PSS<q0.95: 0.95 PSS>q0.95: OBS q0.95 OBS ALARO 0 (4km) PSS: 0.85 PSS<q0.95: 0.95 PSS>q0.95: 0.75 OBS q0.95 OBS ALADIN (40km) PSS: 0.80 PSS<q0.95: 0.86 PSS>q0.95: OBS q0.95 OBS ALADIN (10km) PSS: 0.79 PSS<q0.95: 0.84 PSS>q0.95: OBS q0.95 OBS CNRM (25km) PSS: 0.76 PSS<q0.95: 0.81 PSS>q0.95: X ALARO-0 (40km) ALARO-0 (10km) ALARO-0 (4km) * ALADIN (40km) ALADIN (10km) CNRM (25km) 1e 04 1e Precipitation (mm/day) R. De Troch (RMIB) Multiscale performance of ALARO-0 COST WG / 13

14 Conclusions 1 What is the effect of dynamical downscaling ERA-40 using ALARO-0? Dynamical downscaling of ERA-40 using ALARO-0 adds value to the simulation of extreme daily summer precipitation when compared to ERA Does ALARO-0 give an improvement to ALADIN at varying horizontal resolutions? Frequencies and statistics from Extreme value analysis The new parameterization scheme of ALARO-0 contributes to the improvement in the modelling of extreme precipitation events at varying horizontal resolutions, rather than the increase in spatial resolution. 3 How does ALARO-0 perform within the context of state-of-the-art regional climate modelling? ALARO-0 is a good candidate model for regional climate modelling. R. De Troch (RMIB) Multiscale performance of ALARO-0 COST WG / 13

15 Conclusions 1 What is the effect of dynamical downscaling ERA-40 using ALARO-0? Dynamical downscaling of ERA-40 using ALARO-0 adds value to the simulation of extreme daily summer precipitation when compared to ERA Does ALARO-0 give an improvement to ALADIN at varying horizontal resolutions? Frequencies and statistics from Extreme value analysis The new parameterization scheme of ALARO-0 contributes to the improvement in the modelling of extreme precipitation events at varying horizontal resolutions, rather than the increase in spatial resolution. 3 How does ALARO-0 perform within the context of state-of-the-art regional climate modelling? ALARO-0 is a good candidate model for regional climate modelling. R. De Troch (RMIB) Multiscale performance of ALARO-0 COST WG / 13

16 Conclusions 1 What is the effect of dynamical downscaling ERA-40 using ALARO-0? Dynamical downscaling of ERA-40 using ALARO-0 adds value to the simulation of extreme daily summer precipitation when compared to ERA Does ALARO-0 give an improvement to ALADIN at varying horizontal resolutions? Frequencies and statistics from Extreme value analysis The new parameterization scheme of ALARO-0 contributes to the improvement in the modelling of extreme precipitation events at varying horizontal resolutions, rather than the increase in spatial resolution. 3 How does ALARO-0 perform within the context of state-of-the-art regional climate modelling? ALARO-0 is a good candidate model for regional climate modelling. R. De Troch (RMIB) Multiscale performance of ALARO-0 COST WG / 13

17 Thank you for your attention! Questions? De Troch, R., Hamdi, R., Van de Vyver, H., Geleyn, J.-F. and Termonia, P. (2013). Multiscale Performance of the ALARO-0 Model for Simulating Extreme Summer Precipitation Climatology in Belgium. Journal of Climate 26, R. De Troch (RMIB) Multiscale performance of ALARO-0 COST WG / 13

18 References Gerard, L. and Geleyn, J.-F. (2005). Evolution of a subgrid deep convection parameterization in a limited area model with increasing resolution. Quart. J. Roy. Meteor. Soc. 131, Gerard, L., Piriou, J.-M., Brozkova, R., Geleyn, J.-F. and Banciu, D. (2009). Cloud and Precipitation Parameterization in a Meso-Gamma-Scale Operational Weather Prediction Model. Monthly Weather Review 137, Hamdi, R., Van de Vyver, H. and Termonia, P. (2012). New cloud and microphysics parameterisation for use in high-resolution dynamical downscaling: application for summer extreme temperature over Belgium. Int. J. Climatol. 32, R. De Troch (RMIB) Multiscale performance of ALARO-0 COST WG / 13