Paramétrisation des LiNOx dans Méso-NH Modélisation du cycle de l’ozone dans la haute troposphère : impact des NOx produits par les éclairs. C. Mari, JP. Pinty, P. Mascart, J. Duron, C. Barthe, JP Chaboureau, F. Gheusi, M. Tressol and T. Fehr (DLR) Motivations Paramétrisation des LiNOx dans Méso-NH Applications à TOGA-COARE, TROCCINOX et STERAO Perspectives Méso-NH – Réunion utilisateurs -Toulouse 2005

Comprendre le bilan de l’ozone troposphérique NOx : catalyseurs indispensables pour la production de l’O3 !

Réduire l’incertitude sur les sources de NOx (Lee et al., 1997)

Paramétrisation des LiNOx dans Méso-NH (JP Pinty et T. Fehr) Lightning frequency (Price and Rind 1992) / Cloud Top Height IC/CG rate (Price and Rind, 1994) / Cold cloud thickness P(CG) = 6,7 x 1026 molecules of NO / flash, P(IC) = P(CG) / 10 (Price et al., 1997) LNOx in updrafts and/or in downdrafts Perfectly coherent with transport and scavenging 0°C -10°C IC CG Updrafts Downdrafts Cloud Top

Long-term simulations 1D / TOGA-COARE NO2 (LiNOx) – NO2 (No LiNOx) Upper troposphere: Accumulation Free troposphere: Competition LNOx vs. convective transport PBL: Increase of NOx due to downdraft transport of LNOx

O3 (LiNOx) - O3 (NO LiNOx) Long-term simulations 1D / TOGA-COARE LNOx = local and sporadic event but integrated effect in space and time for ozone

Meso-NH Set-up for regional (low-resolution) simulations EU-TROCCINOX One single domain (same as forecast mode) horizontal grid: 102 x 102 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 (incl. scavenging and LiNOx) microphysics: Pinty-Jabouille, subgrid cloudiness surface: ISBA and TEB radiation: ECMWF Initialization/coupling with ARPEGE-MOCAGE analysis Lagrangian tracers Chemistry ReLACS scheme (37 species) dry deposition: Wesely emissions: EDGAR/GEIA (1°x1°) (except for BB, Yevich and Logan 2003)

03/03/04 Morning flight survey 03/03/04 Local convection flight in the afternoon 04/03/04 Aged NOx plume in the afternoon

Modelling of LNOx in MNHC at high resolution [ JP Pinty, C. Mari, C. Barthe and JP Chaboureau] The STERAO intercomparison case [courtesy of M. Barth, NCAR) http://box.mmm.ucar.edu/individual/barth/Chem_Convec_Intercomparison/slide1.html

Set-up of Méso-NH Domain horizontal grid : 120 x 120 points at 1 km resolution with open LBC 50 levels : from 70 m (bot) up to 600 m (top) with wave damping Physics transport with MPDATA scheme microphysics: Pinty-Jabouille electricity: Barthe-Pinty-Molinié gas scavenging & LiNOx: Mari-Pinty 3D turbulence (TKE): Cuxart-B-R Initialization R/S with 3 warm bubbles (3K) profiles of HCHO, H2O2, HNO3 profiles of CO, NOx, O3 3 hour run on the 12 LINUX cluster @ LA Ice and Wind fields T=1 hour @ Z=10 km Case study coming from Skamarock et al. (2000) and Barth et al. (2001) published in JGR.

Convective Transport and scavenging Time = 1 hour Time = 2.5 hours 75 ppb<CO<130 ppb HNO3

http://box.mmm.ucar.edu/individual/barth/Chem_Convec_Intercomparison/slide1.html

Perspectives Modèle couplé transport / lessivage / éclairs / chimie dans la convection, complet et réaliste Tests de sensibilité 1D (stage de H. Luitjing au LA ) Amélioration de la paramétrisation: approche plus physique, comparaison avec des simulations explicites de type STERAO (stage post-doctoral C. Barthe)