multiscale performance of the alaro-0 model for...

Multiscale performance of the ALARO-0 model forsimulating extreme summer precipitation climatology in

Belgium

Rozemien De Troch1,2, Rafiq Hamdi1, Hans Van de Vyver1,Jean-Francois Geleyn2,3, Piet Termonia1,2

1Royal Meteorological Institute of Belgium; 2Department of Physics and Astronomy, GhentUniversity, Ghent, Belgium; 3Czech Hydrometeorological Institute, Prague, Czech Republic

COST Action WG1+2 Meeting on Parameterization and DownscalingJanuary 29-30, 2014, Milan

R. De Troch (RMIB) Multiscale performance of ALARO-0 COST WG1+2 2014 1 / 13

1 Introduction

2 Experimental Design

3 Results

4 Conclusion

R. De Troch (RMIB) Multiscale performance of ALARO-0 COST WG1+2 2014 2 / 13

Models

ARPEGE-IFSGLOBAL

ALADINLIMITED AREA MODEL (LAM)

+New physics

parameterizations centered around

improved convection and cloud scheme

ALARO-0MESOSCALE AND

CONVECTIVE SCALE = “GREY-ZONE” SCALES

= 3MT

(Gerard and Geleyn, 2005; Gerard et al., 2009)

R. De Troch (RMIB) Multiscale performance of ALARO-0 COST WG1+2 2014 3 / 13

Context8 km 4 km Radar (obs.)

2 km 1 km 1 km (no 3MT)

R. De Troch (RMIB) Multiscale performance of ALARO-0 COST WG1+2 2014 4 / 13

Goal

Explore the relative importance of resolution versusparameterization formulation on the model skill to simulate

realistic extreme daily precipitation

R. De Troch (RMIB) Multiscale performance of ALARO-0 COST WG1+2 2014 5 / 13

Experimental Design

ERA-40 reanalysis1961-1990

ALARO-0 40 km1961-1990

ALADIN 40 km1961-1990

ALARO-0 10 km1961-1990

ALARO-0 4 km1961-1990

ALADIN 10 km1961-1990

DYNAMICALDOWNSCALING

ONE-WAY NESTING

DRIVING LAM

HIGH RESOLUTION

LAM

GLOBAL REANALYSIS

ALADIN-ClimateCNRM 25 km1961-1990

ENSEMBLES

Station Observations1961-1990

R. De Troch (RMIB) Multiscale performance of ALARO-0 COST WG1+2 2014 6 / 13

Experimental Design

ALARO-0 10 km1961-1990

ALARO-0 4 km1961-1990

ALADIN 10 km1961-1990

ONE-WAY NESTING

HIGH RESOLUTION

LAM

GLOBAL REANALYSIS

ALADIN-ClimateCNRM 25 km1961-1990

ENSEMBLES

Station Observations1961-1990

DRIVING LAM

ERA-40 reanalysis1961-1990

ALARO-0 40 km1961-1990

ALADIN 40 km1961-1990

DYNAMICALDOWNSCALING

(i) What is the effect of dynamical downscaling ERA-40 using ALARO-0?

R. De Troch (RMIB) Multiscale performance of ALARO-0 COST WG1+2 2014 6 / 13

Experimental Design

DRIVING LAM

ERA-40 reanalysis1961-1990

DYNAMICALDOWNSCALING

ALARO-0 40 km1961-1990

ALADIN 40 km1961-1990

ALARO-0 10 km1961-1990

ALARO-0 4 km1961-1990

ALADIN 10 km1961-1990

ONE-WAY NESTING

HIGH RESOLUTION

LAM

GLOBAL REANALYSIS

ALADIN-ClimateCNRM 25 km1961-1990

ENSEMBLES

Station Observations1961-1990

(ii) Does ALARO-0 give an improvement to ALADIN at varying horizontal resolutions?

R. De Troch (RMIB) Multiscale performance of ALARO-0 COST WG1+2 2014 6 / 13

Experimental Design

ERA-40 reanalysis1961-1990

ALARO-0 40 km1961-1990

ALADIN 40 km1961-1990

ALARO-0 10 km1961-1990

ALARO-0 4 km1961-1990

ALADIN 10 km1961-1990

DYNAMICALDOWNSCALING

ONE-WAY NESTING

HIGH RESOLUTION

LAM

GLOBAL REANALYSIS

ALADIN-ClimateCNRM 25 km1961-1990

ENSEMBLES

Station Observations1961-1990

DRIVING LAM

(iii) How does ALARO-0 perform within the context of state-of-the-art regional climate

modelling?

R. De Troch (RMIB) Multiscale performance of ALARO-0 COST WG1+2 2014 6 / 13

Observations

0

50

100

150

200

250

300

350

400

450

500

550

600

650m

R. De Troch (RMIB) Multiscale performance of ALARO-0 COST WG1+2 2014 7 / 13

(i) Effect of downscaling ERA-40

0 10 20 30 40 50 60 70 80 90 100 110

1e−06

1e−04

1e−02

1e+00

1e+02 OBSq0.95 OBSERA40 PSS: 0.76 PSS<q0.95: 0.89 PSS>q0.95: 0.62ALARO−0 (40km) PSS: 0.85 PSS<q0.95: 0.95 PSS>q0.95: 0.75ALADIN (40km) PSS: 0.80 PSS<q0.95: 0.86 PSS>q0.95: 0.75

Precipitation (mm/day)

Relat

ive fre

quen

cy (lo

g)

R. De Troch (RMIB) Multiscale performance of ALARO-0 COST WG1+2 2014 8 / 13

(ii+iii) Improvement of ALARO-0

40 km

10 km

4 km

ALARO-0

OBS

ALADIN

CNRM

25 km

R. De Troch (RMIB) Multiscale performance of ALARO-0 COST WG1+2 2014 9 / 13

(ii+iii) Improvement of ALARO-0

1e−06

1e−04

1e−02

1e+00

1e+02

0 30 60 90 120 160

OBS

q0.95 OBS

ALARO−0 (40km)

PSS: 0.85

PSS<q0.95: 0.95

PSS>q0.95: 0.75

0 30 60 90 120 160

OBS

q0.95 OBS

ALADIN (40km)

PSS: 0.80

PSS<q0.95: 0.86

PSS>q0.95: 0.75

0 30 60 90 120 160

OBS

q0.95 OBS

CNRM (25km)

PSS: 0.76

PSS<q0.95: 0.81

PSS>q0.95: 0.70

1e−06

1e−04

1e−02

1e+00

1e+02

0 30 60 90 120 160

Relat

ive fr

eque

ncy (

log)

Precipitation (mm/day)

X ALARO-0 (40km)● ALARO-0 (10km)♦ ALARO-0 (4km)* ALADIN (40km)▲ ALADIN (10km)■ CNRM (25km)

OBS

q0.95 OBS

ALARO−0 (10km)

PSS: 0.86

PSS<q0.95: 0.95

PSS>q0.95: 0.76

0 30 60 90 120 160

OBS

q0.95 OBS

ALADIN (10km)

PSS: 0.79

PSS<q0.95: 0.84

PSS>q0.95: 0.74

1e−06

1e−04

1e−02

1e+00

1e+02

0 30 60 90 120 160

OBS

q0.95 OBS

ALARO−0 (4km)

PSS: 0.85

PSS<q0.95: 0.95

PSS>q0.95: 0.75

R. De Troch (RMIB) Multiscale performance of ALARO-0 COST WG1+2 2014 10 / 13

Conclusions

1 What is the effect of dynamical downscaling ERA-40 usingALARO-0?⇒ Dynamical downscaling of ERA-40 using ALARO-0 adds value to

the simulation of extreme daily summer precipitation whencompared to ERA-40.

2 Does ALARO-0 give an improvement to ALADIN at varyinghorizontal resolutions?⇒ Frequencies and statistics from Extreme value analysis −→ The

new parameterization scheme of ALARO-0 contributes to theimprovement in the modelling of extreme precipitation events atvarying horizontal resolutions, rather than the increase in spatialresolution.

3 How does ALARO-0 perform within the context ofstate-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 WG1+2 2014 11 / 13

Conclusions

1 What is the effect of dynamical downscaling ERA-40 usingALARO-0?⇒ Dynamical downscaling of ERA-40 using ALARO-0 adds value to

the simulation of extreme daily summer precipitation whencompared to ERA-40.

2 Does ALARO-0 give an improvement to ALADIN at varyinghorizontal resolutions?⇒ Frequencies and statistics from Extreme value analysis −→ The

new parameterization scheme of ALARO-0 contributes to theimprovement in the modelling of extreme precipitation events atvarying horizontal resolutions, rather than the increase in spatialresolution.

3 How does ALARO-0 perform within the context ofstate-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 WG1+2 2014 11 / 13

Conclusions

1 What is the effect of dynamical downscaling ERA-40 usingALARO-0?⇒ Dynamical downscaling of ERA-40 using ALARO-0 adds value to

the simulation of extreme daily summer precipitation whencompared to ERA-40.

2 Does ALARO-0 give an improvement to ALADIN at varyinghorizontal resolutions?⇒ Frequencies and statistics from Extreme value analysis −→ The

new parameterization scheme of ALARO-0 contributes to theimprovement in the modelling of extreme precipitation events atvarying horizontal resolutions, rather than the increase in spatialresolution.

3 How does ALARO-0 perform within the context ofstate-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 WG1+2 2014 11 / 13

Thank you for your attention!Questions?

rozemien.detroch@meteo.be

De Troch, R., Hamdi, R., Van de Vyver, H., Geleyn, J.-F. andTermonia, P. (2013).Multiscale Performance of the ALARO-0 Model for SimulatingExtreme Summer Precipitation Climatology in Belgium.Journal of Climate 26, 8895–8915 .

R. De Troch (RMIB) Multiscale performance of ALARO-0 COST WG1+2 2014 12 / 13

References

Gerard, L. and Geleyn, J.-F. (2005).Evolution of a subgrid deep convection parameterization in alimited area model with increasing resolution.Quart. J. Roy. Meteor. Soc. 131, 2293–2312.

Gerard, L., Piriou, J.-M., Brozkova, R., Geleyn, J.-F. and Banciu, D.(2009).Cloud and Precipitation Parameterization in a Meso-Gamma-ScaleOperational Weather Prediction Model.Monthly Weather Review 137, 3960–3977.

Hamdi, R., Van de Vyver, H. and Termonia, P. (2012).New cloud and microphysics parameterisation for use inhigh-resolution dynamical downscaling: application for summerextreme temperature over Belgium.Int. J. Climatol. 32, 2051–2065.

R. De Troch (RMIB) Multiscale performance of ALARO-0 COST WG1+2 2014 13 / 13