Workshop Bauru STUDY OF THE IMPACT OF THE 8 FEB 2001 CONVECTIVE SYSTEM ON THE UTLS AIR COMPOSITION V. Marécal 1, E. D. Rivière 1, G. Held 2, S. Cautenet 3, S. Freitas 4 and N. Larsen 5 1 LPCE, Orléans, France, 2 IPMet, Bauru, Brazil 3 LAMP, Clermont-Ferrand, Fance 4 CPTEC, Cachoeira Paulista, Brazil 5 DMI, Copenhagen, Denmark
Workshop Bauru 2004 SCIENTIFIC OBJECTIVE What is the local impact of deep convection on the TTL composition ? TOOLS: - 3D meso-scale simulation with on line chemistry using the RAMS-Chemistry model - Available meteorological and chemistry data UTLS TTL stratosphere Boundary layer free troposphere Tropics Mid-latitudes emissions tropopause « overshoot » deep convection 11 km 17 km 0 km 2 What is the relative contribution of transport and chemistry ?
Workshop Bauru 2004 CASE STUDY: THE 8 FEB 2001 CONVECTIVE SYSTEM 3 BAURU RADAR REFLECTIVITY MEASUREMENTS 02 : 01: 16 9 FEB : 01: 16 9 FEB : 01: 16 9 FEB : 01: 16 8 FEB : 01: 16 8 FEB : 01: 16 8 FEB : 01: 16 8 FEB : 01: 16 8 FEB : 01: 16 8 FEB : 01: 16 8 FEB 2001
Workshop Bauru 2004 STEP 1: METEOROLOGICAL SIMULATION 4 SIMULATION SETUP - 42 hours from 2001/02/07 12UT - 2 nested grids Grid 1: 20 km horizontal resolution Grid 2: 4 km horizontal resolution - 61 vertical levels from surface to 30km altitude (500m in the UTLS) - Initialisation from ERA40 analysis and radiosoundings - Subgrid scale convective parameterization for Grid 1 from Freitas et al (2004) Grid 1 Grid 2
Workshop Bauru 2004 STEP 1: METEOROLOGICAL SIMULATION 5 Surface rainfall accumulated from 2001/02/08 15UT to 2001/02/09 00UT from the Bauru radarfrom the RAMS model
Workshop Bauru CHEMISTRY SETUP -29 species and 71 reactions - Gaseous and aqueous chemistry - Surface emissions of ozone precursors - Parametrization of NO x production by lightning - Initialisation from MOCAGE (Météo-France) global fields STEP 2: SIMULATION WITH ON-LINE CHEMISTRY
Workshop Bauru DOES THE MODEL PRODUCE REALISTIC OZONE PROFILES ? 2004 DMI O 3 measurement range TTL
Workshop Bauru WHAT ARE THE MAIN CONTRIBUTIONS TO THE OZONE BUDGET IN THE TTL ? = 380 K 30 km 13 km E w N S z Ozone budget in the TTL between Feb. 00UT and Feb 00UT ch = 11 (* molec of O 3 ) VerticalMerid.ZonalChem. (in % of the total O 3 increase) 40 %144 %-89 %5 % Grid 2 23 % STE 17 % 13 km flux
Workshop Bauru WHAT ORIGINATES THE STRATOSPHERE-TROPOSPHERE EXCHANGE ? Horizontal cross-section of vertical velocity at 17.5 km Wave activity generated by deep convection originates STE 1200 UT 2200 UT
Workshop Bauru 2004 WHY THE CONTRIBUTION OF CHEMISTRY TO THE OZONE BUDGET IN THE TTL IS WEAK ? Accumulated O 3 production in ppbv (Grid 2 average) 10 TTL NO x in ppbv (Grid 2 average) CO in ppbv (Grid 2 average)
Workshop Bauru CONCLUSION UTLS Tropics tropopause Convective outflow deep convection Large scale flow LNO x O 3 prod Additional O 3 prod TTL Boundary layer free troposphere O 3 precursor emission stratosphere 13 km 17 km 0 km Wave from convection STE Additional O 3 prod
Workshop Bauru 2004 FUTURE WORK 12 * IMPLEMENTATION OF THE CPTEC TRAJECTORY CODE FOR CHEMICAL SPECIES * IMPLEMENTATION OF THE RTTOV CODE FOR « MODEL TO SATELLITE » COMPARISONS * SIMULATIONS FOR THE FEB 2004 CASE STUDY (SF2) AND THE 24 FEB 2004 CASE STUDY (SF4) *FURTHER ANALYSIS OF THE 8 FEB 2001 CASE STUDY: ROLE OF SOLUBLE SPECIES (OH, HNO 3 ) SIMILAR ANALYSIS ON A LONGER SIMULATION
Workshop Bauru 2004 SIMULATION OF THE FEB 2004 CASE STUDY 13 GOES image 13 feb UT Vertically-integrated total condensate in mm from model simulation: 13 feb UT Vertically-integrated total condensate in mm from model simulation: 14 feb UT Time shift possibly related to initialisation from ECMWF analysis Planned work: initialisation with NCEP or CPTEC products
Workshop Bauru MANY THANKS TO Ana Maria Gomes and IPMet collaborators Gilles Foret - LaMP INMET Vincent-Henri Peuch – Météo-France Jean Luc Athié – LA Publications submitted to ACDP: Modelling study of the impact of deep convection on the UTLS air composition. Par I: Analysis of ozone precursors. Marécal et al. Modelling study of the impact of deep convection on the UTLS air composition. Par II: Ozone budget in the TTL. Rivière et al.