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The atmospheric transport of biomass burning and anthropogenic emissions in South America an Africa Continents has been monitored by CPTEC in collaboration with the University of São Paulo <>. A real time operational monitoring transport system was implemented using the on-line 3-D transport model CATT-BRAMS (Coupled Aerosol and Tracer Transport to the Brazilian developments on the Regional Atmospheric Modelling System) coupled to an emission model. In this method, the mass conservation equation is solved for carbon monoxide (CO) and particulate material PM2.5. Source emissions of gases and particles associated with biomass burning activities in tropical forest, savanna and pasture are parameterized and introduced in the model. The sources are spatially and temporally distributed and daily assimilated according to the biomass burning spots obtained by remote sensing. Anthropogenic sources of CO are also included following the EDGAR 3.0 database. The advection, at grid scale, and turbulent transport, at sub-grid scale, are provided by the RAMS parameterizations. A sub-grid transport parameterization, associated to wet and deep and shallow circulation not explicitly resolved by the model due its low spatial resolution, is also introduced. Sinks, associated with generic process of removal/transformation of gases/particles, are parameterized and introduced in the mass conservation equation.

Modell devellopmentt hiisttoriicall
The present model had its development initiated during the Ph. D. program of Saulo Freitas and Karla Longo at Physics Institute of the University of São Paulo under the adviser of the Professors Maria Assunção Silva Dias and Paulo Artaxo, in collaboration with Professor Pedro Silva Dias.
Further improvements were carried out at NASA Ames Research Center in collaboration with Dr. Robert Chatfield and Dr. Georg Grell (NOAA – FSL). Nowadays, the model development is on progress at CPTEC-INPE in collaboration with USP.

Modell Descriipttiion
Brazilian Regional Atmospheric Modelling System (BRAMS)

The BRAMS is a multipurpose, numerical prediction model designed to simulate atmospheric circulations spanning in scale from hemispheric scales down to large eddy simulations (LES) of the planetary boundary layer ( The equation set used is the quasi-Boussinesq nonhydrostatic equations described by Tripoli and Cotton (1982). The model is equipped with a multiple grid nesting scheme which allows the model equations to be solved simultaneously on any number of interacting computational meshes of differing spatial resolution. It has a complex set of packages to simulate processes such as: radiative transfer, surface-air water, heat and momentum exchanges, turbulent planetary boundary layer transport and cloud microphysics. The initial conditions can be defined from various observational data sets that can be combined and processed with a mesoscale isentropic data analysis package (Tremback, 1990). For the boundary conditions, the 4DDA schemes allow the atmospheric fields to be nudged towards the large-scale data. From a computational point of view, BRAMS is a very efficient parallel code that can be run at several platforms. Recently, a new deep and shallow convective scheme based on the mass flux approach and with several types of closure (Grell and Devenyi, 2002) were implemented. This cumulus scheme is suitable for mesoscale runs (horizontal grid spacing about 20 km) and so for regional transport studies.

Model parameterizations are:

• The horizontal diffusion coefficients are based on the Smagorinsky (1963) formulation.
• The vertical diffusion is parameterized according to the Mellor and Yamada (1974) scheme, which employs a prognostic of the turbulent kinetic energy.
• The short and longwave radiative transfer are evaluate by the Chen and Cotton (1983) scheme that accounts for condensate in the atmosphere.
• The surface-atmosphere water, momentum and energy exchange are simulated by the Land Ecosystem Atmosphere Feedback model (LEAF-2), which represents the storage and vertical exchange of water and energy in multiple soil layers, including effects of freezing and thawing soil, temporary surface water or snowcover, vegetation, and canopy air (Walko et al., 2000).
• The advection scheme is a forward–upstream of second-order Tremback et al, (1987).
• Bulk microphysics (Walko et al., 2000)
• A new convective cumulus scheme based on Grell (1993), Grell and Devenyi (2002).
• The 4D data assimilation, a ‘nudging’ type scheme in which the model fields can be nudged
toward observational data as a simulation progresses.

Coupled Aerosol and Tracer Transport model to BRAMS (CATT-BRAMS)
The CATT-BRAMS explores the BRAMS tracer transport capability of using slots for scalars. The inline model transport follow the Eulerian approach, solving the mass conservation equation for carbon monoxide (CO) and particulate material PM2.5, where the tracer mixture ratio, s (=?/?air), is calculated using the mass conservation equation

where adv, PBL turb and deep conv stand for grid-scale advection, sub-grid transport in the planetary boundary layer (PBL) and sub-grid transport associated to moist and deep convection, respectively. W accounts for the convective wet removal for PM2.5, R is a sink term associated with generic process of removal/transformation of tracers (dry deposition for PM2.5 and chemical transformation for CO), and Q is the source emission associated to the biomass burning process.
The advection and PBL turbulent transport schemes are from the BRAMS. The sub-grid transport associated with deep and shallow convective transport are coupled to the Grell cumulusscheme (Freitas et al., 2003). A tracer convective transport coupled to the Grell cumulus parameterization was also implemented in the model. For PM2.5, the tracer convective transport scheme accounts also for the wet (in and below cloud) removal based on the work of Berge (1993).
Also, an additional radiation parameterization, which takes the interaction between aerosol particles and short and long wave radiation using the rapid two-stream approximation (Toon, et al., 1989) and the aerosol scattering and absorption calculated with the Mie code for stratified spheres (Toon and Ackerman, 1981) was implemented. The coupling with the chemical mechanism of the MOZART model (Model of Ozone And Related Tracers) (Brasseur et al., 1998; Horowitz et al., 2003) is under development at CPTEC.

Source emission parameterization

A biomass burning tracer emission parameterization based on the work of Freitas (1999) was implemented. The biomass burning source emission parameterization (for CO, CO2, CH4, NOx and PM2.5) is based on the GOES-12 WF_ABBA fire product (Prins et al., (1998), and GOES-12, AVHRR and MODIS fire observation from CPTEC-INPE ( and field observations. For each fire detected by remote sensing, the mass of emitted tracer is calculated (details: source emission) and its emission in the model follows a diurnal cycle of the burning (emission rate). The type of vegetation that is burning is obtained from the IGBP-INPE 1km vegetation map ( and ( The sources are spatially and temporally distributed and daily assimilated according to the biomass burning spots defined by the satellite observations. All biomass burning emissions are added with the EDGAR “agricultural waste burn” and “fuelwood burning” emissions with 1x1 degree horizontal resolution and 1 year time resolution (see pictures). On African continent, the biomass burning emissions are defined always following the EDGAR prescription.
The carbon monoxide emission associated to the anthropogenic process (industrial, power generation, transportation, etc) is provided by EDGAR ( database with a CETESB correction for São Paulo Metropolitan Area (CETESB/2002).

Productt descriipttiion
Model configuration, initial and boundary conditions

The model is set up with 2 grids at horizontal resolution of 160 and 40 km, respectively. The vertical resolution starts at 150 m near the surface, stretching at a rate of 1.15 to a final resolution of 850 m, with the model top at about 21 km. The coarse grid, covering the South American and African continents, is intended to generate the tracer inflow from Africa to South America. The atmospheric model is initialized and nudged with CPTEC global model (6 hours 1.875 degrees) analysis/forecast data. The 3D tracer concentration fields of the previous run are used as the tracer initial condition for the next, and the constant inflow condition is used to the tracer boundary condition in the coarse grid.
The simulation is performed for 48 hours, beginning at 00 UTC of the previous day. The soil moisture is initialized based on the antecedent precipitation index method (Gevaerd and Freitas, 2003). Analysis and forecast of carbon monoxide and aerosol particles mass concentration, aerosol optical thickness, and aerosol particle mass wet deposited fields are provided daily at Comparison of the model results with remote sensing aerosol and trace gases products and direct measurements has been demonstrating the good predictability skills of the method.

Modell x Observattiion
1999 case study

Comparison between PM2.5 columnar (mg/m2) and the Aerosol Index from Total Ozone Mapping Spectrometer (TOMS) instruments ( for 1500Z September 01 and 1500Z August 24 1999 with the smoke plume following the anticyclone circulation over the Atlantic Ocean.

2002 case study
Comparison of the aerosol optical thickness (550 nm channel) derived from MODIS-TERRA observation and calculated from the model (combination of the regional grid and coarse grid) for August 27 2002. A smoke corridor is evident and it was associated with na anticyclone circulation centered over the Atlantic Ocean. The long-range transport of smoke results in transboundary air pollution with smoke- laden air crossing into South American countries, like Paraguay, Argentina and Uruguay.

Winds and columnar particulate material for August 25 2002. The detail shows the true color image from MODIS-TERRA observation at 14:05 Z at the same day.

High troposphere and long range transport of carbon monoxide. Comparison with CO from MOPITT.

Time series (07/September-22/October 2002) of particulate mass concentration (um/m3) from the model, surface TEOM measurement (Artaxo – IF USP) at Fazenda Nossa Senhora – Ji-Paraná – Ro, and MODIS derived data.

Karla Longo / Saulo Freitas, CPTEC-INPE
Maria Assunção da Silva Dias, DCA-USP
Pedro Leite da Silva Dias, DCA-USP
Alberto Setzer, CPTEC-INPE
Elaine Prins, NOAA-NES DIS/ORA
Robert Chatfield, NASA Ames
Paulo Artaxo, IF-USP
Georg Grell, NOAA/FSL
Carlos Nobre, CPTEC-INPE

Contacts: and/or


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