Objective Evaluation of the Meso-NH Simulations during

Hibiscus-Troccinox-Troccibras

I. Forecasts for the TROCCINOX campaignII. Three case studies: 13 Feb, 24 Feb, 3 March

J.-P Chaboureau, J.-P. Cammas, J. Duron, F. Gheusi, C. Mari, P. J. Mascart,

J.-P. Pinty

Laboratoire d’Aérologie (UPS/CNRS) Toulouse, France

I. Forecasts for the CampaignDaily real-time runs from 27 January to 5 March 2004 posted on http://www.aero.obs-mip.fr/mesonh/troccinox

• One single domain

• horizontal grid: 100 x 100 points at 30 km resolution

• 72 levels: from 40 m (bottom) up to 600 m (top)

• Physics

• turbulence: CBR TKE 1D scheme

• convection: Bechtold’s scheme

• microphysics: Pinty-Jabouille

• surface: ISBA

• radiation: ECMWF

• Initialization/coupling with ECMWF forecasts

• Lagrangian tracers

• Simulated GOES-E brightness temperature (Tb)

3000 km

3000 km

Model-to-satellite Approach

GOES-E 11 m Tb

Meso-NH SUBG with cloud fraction=f(Q1)

+24 h+24 h

+24 h+24 h

Meso-NH CTRL without cloud fraction

11 m Tb

00 UTC 24 Feb

Direct compariso

n

Cloud top height

13-14 FebFalcon+SF2

30-day Objective EvaluationFull domain3000x3000

km2

Bauru area 150x150 km2

24 FebSF4

3-4 MarchFalcon

IR Tb

Correlation

IR Tb

Diurnal Cycle over Bauru Area

30-day average

Bauru area 150x150 km2

Precipitation

IR TbSurface Flux

CAPE/CIN

Time Evolution over Bauru

Bauru area 150x150 km2

min(TB)<205 K Min(TB)<205 K

Precipitation

IR Tb

CAPE

Time-Longitude Diagram

Data averaged within 75 km around Bauru

Precipitation% of Tb<205K

GOES-E TbMeso-NH Tb

II. Three Case Studies

Preliminary work for three cases:

- 13-14 Feb, 24-25 Feb, and 3-4 March

Same setup as for the forecasts (x=30 km), but:

– coupling with analyses (instead of ECMWF forecast)

– use of the subgrid cloud scheme

Comparisons with:

- Meteosat Second Generation observations

- Falcon and SF2/4 measurements

Comparison with MSG at 10.8 m

Mete

osat-

8M

eso-N

H

00 UTC 14 Feb 00 UTC 25 Feb 00 UTC 4 March

Comparison with MSG at 3.9 m

Mete

osat-

8M

eso-N

H

00 UTC 14 Feb 00 UTC 25 Feb 00 UTC 4 March

Comparison with Falcon Flights

48 h Meso-NH run 36 h Meso-NH run Falcon flight

1719-2055 UTC 3 March

1650-2015 UTC

14 Feb

Data from DLR

Comparison with SF2 and SF4

13-14 Feb.

Data from G. Durry (CNRS)

24-25 Feb.

ConclusionsI. Forecasts for the TROCCINOX campaign

• better agreement with satellite observation when using the subgrid cloud scheme

• diurnal cycle of precip. in advance by 3 hours

• Deep convection events with Tb<205K more frequent during cold front episodes

II. Three case studies

• encouraging results when comparing with satellite and in-situ observations