The ICTP RegCM System and Aerosol Modeling F. Giorgi, F. Solmon, A. Zakey ICTP, Trieste, Italy Contributions from A. Shalaby, A. Konare, Goldschmidt 2009 Conference, Davos, Switzerland, June 2009

Flexible, user-friendly modeling system Adaptable to any region of the World Used by a wide scientific community Used for a wide range of applications Coupled atmosphere – ocean version Capability of interactive vegetation (CLM, IBIS) Capability of interactive aerosol/chemistry The ICTP Regional Climate Model RegCM4

Sample of RegCM domains used ΔX= KM

Tracer model / RegCM3 Transport Removal terms Primary Emissions Physico – chemical transformations Strongly dependent on the nature of the tracer General approach Particles and chemical species considered (12 tracers). Sea-Salt (2 bins) µm µm “Simple” Aerosols in RegCM4 Qian and Giorgi 1999; Qian et al. 2001; Solmon et al. 2006; Zakey et al. 2006; 2008

Climate-aerosol model coupling Regional Climate Model Radiative Transfer Package SW and LW Aerosol Model Source, Transport, Removal Radiative Fluxes Heating Rate Aerosol Radiative Forcing Clouds, Temperature, Water Vapor Winds, PBL Processes Clouds, Precipitation Aerosol Concentration Simple indirect effect scheme Rc = f(χ) Aerosol Concentration Cloud Reflectivity Semi-directeffects

During the last decades East Asia has been one of the most rapidly developing regions of the worldDuring the last decades East Asia has been one of the most rapidly developing regions of the world As a result, anthropogenic aerosol emissions over the region have considerably increased, thereby (possibly) affecting the climate of the regionAs a result, anthropogenic aerosol emissions over the region have considerably increased, thereby (possibly) affecting the climate of the region A series of studies investigated the possible regional climatic effects of anthropogenic aerosols over East AsiaA series of studies investigated the possible regional climatic effects of anthropogenic aerosols over East Asia –Qian and Giorgi (1999,2000), Qian et al. (2001, 2003), Chameides et al. (1999,2002),Streets and Waldhoff (2000),Kaiser and Qian (2002),Giorgi et al. (2002,2003) Example I East Asia

Aerosol extinction coefficient averaged for Kaiser and Qian (2002) Change of observed mean temperature ( o C) in China Qian and Giorgi (2000)

SO2 Burden, DJF, CONT SO4 Burden, DJF, CONT SO4 Burden, JJA, CONT SO2 Burden, JJA, CONT

Temperature, DJF, IND1-CONT Temperature, JJA, IND1-CONT Temperature, MAM, IND1-CONT Temperature, SON, IND1-CONT

Example II: Effect of dust on the African monsoon Solmon et al Zakey et al Konare et al 2008 Solmon et al. 2008

SeaWIFS (NGSFC) TOMS (aerosol index) RegCM ( µm dust burden) Zakey et al, 2006 Case study: Dust storm of February 2000

RegCM AOD MISR AOD JJA ( ) RegCM Lidar M’Bour Validation in “climate” mode Konaré et al., 2008; Solmon et al., 2008

Precipitation Dust - nodust Precipitation, CRU ( ) – ( ) The dust forcing can strengthen the occurrence of drought in the Sahel

Land surface sub-grid scale model in RegCM4 (Giorgi et al. 2003) Define a regular fine scale sub-grid for each coarse scale model grid-box. –Landuse, topography, and soil are characterized on the fine grid. Disaggregate climatic fields from the coarse grid to the fine grid (e.g. temperature, precipitation). –Disaggregation technique based on the elevation differences between the coarse grid and the fine grid. Perform BATS surface physics computations on the fine grid. Reaggregate the surface fields from the fine grid to the coarse grid. 60-km Mean Landuse and Elevation

Numerical Experiments 10-km 15-km 60-km Simulation period: 1 Oct 1994 to 1 Sept 1995 Land Surface computations performed on subgrid. –CTL 60-km; no subgrid cells –EXP15 15-km; 16 subgrid cells –EXP10 10-km; 36 subgrid cells

Results: Temperature WINTER (DJF) OBS (CRU)CTL SUMMER (JJA) OBS (CRU)CTL EXP15EXP10 EXP15EXP10

Results: Snow WINTER (DJF) CTL SPRING (MAM) CTL EXP15EXP10 EXP15EXP10 Station OBS

Domain envisioned for PAPRIKA CORDEX Domain Dx = 50 km PAPRIKA Nested Domain Dx = km Sub-Grid Scheme, Dx=2-3 km

Key questions from the regional modeling side What model development is needed? –Coupling with a “snow/glacier” module –Use simple parameterizations of snow albedo as a function of BC and Dust –Disaggregation of precipitation and temperature What data can be used for model validation? –Atmospheric data –Other data? What simulations will be performed? –RCM domain/resolution? –GCM(s)? –Scenarios? –Time slices?

THANK YOU

m.s -1 mm/day 15 Mean circulation at 865 hpa ( NODUST, JJA ) Differential circulation at 865 hpa m.s -1 mm/day ( DUST -NODUST, JJA ) Konaré et al., 2008; Solmon et al., 2008 Dynamical and precipitation response to dust forcing response to dust forcing

2 : ‘Elevated heat pump’ effect ( Lau et al., 2009) 1: Weakening of the ‘monsoon pump’ Solmon et al., 2008 Dust heating rate Cloud water, meridional circulation and precipitation difference Dust – Nodust, 15W-15E Average

ICTP Regional Climate Model RegCM4 Dynamics: MM5 Hydrostatic (Giorgi et al. 1993a,b) Radiation: CCM3 (Kiehl 1996) Large-Scale Clouds & Precipitaion: SUBEX (Pal et al 2000) Cumulus convection: Grell (1993) Anthes-Kuo (1977) MIT (Emanuel 1991) Boundary Layer: Non-local, Holtslag (1990) Aerosols: SO4, OC, BC (Solmon et al 2005) Dust (Zakey et al 2006) Sea salt (Zakey et al. 2009) Gas phase chemistry: Shalaby et al Land Surface: BATS (Dickinson et al 1993) SUB-BATS (Giorgi et al 2003) CLM (Steiner et al 2009) Tropical Band Coupled Lake (Host. Et al. 1994) Coupled Ocean MIT (Artale et al. 2010) ROMS (Ratnam et al. 2009)

The RegCM regional climate model system Participation to intercomparison projects PIRCS (US, ISU) NARCCAP (US, UCSC) PRUDENCE (Europe, ICTP) ENSEMBLES (Europe, ICTP) CECILIA (Central Europe, Central-Eastern European partners) AMMA (West Africa, ICTP, African partners) CLARIS (South America, U. Sao Paulo) RMIP (East Asia, CMA) CORDEX (Multiple domains, RegCNET)

Countries where RegCM is used

Number of papers using RegCM (from the ISI)