3 rd LBA Science Conference, Brasilia, July 2004 The relationship between biomass burning aerosols, cloud condensation nuclei and cloud stucture in Amazonia * Crystal collection * Coalescence Diffusion Crystal shattering * * * * SO 4 - SO 2 Nucleation Evaporation Collection Paulo Artaxo, Meinrat O. Andreae, Daniel Rosenfeld, Goran Frank, Pascal Guyon, Luciana V. Rizzo, Theotonio Pauliquevis, Maria A. F. Silva Dias and many others
Control of radiation balance and precipitation Rain Rain Cloud Condensation Nuclei Water vapor Vegetation emitting terpenes, primary aerosol particles and water vapor
Isopreno (gas) 2-methilthertiol (partículas) From Clayes et al., Science March 2004) Natural Production of CCN in Amazonia 1) Primary biogenic particles 2) Secondary organic aerosol from terpenes and isoprene 3) Coated soil dust (?) 4) Sulfates and nitrates (?)
Natural and polluted clouds in Amazonia Naturally: low CCN (200-300 #/cc) Large droplets (>30 microns) Rapid development to large droplets Low reflectivity clouds Polluted: High CCN (>3000 #/cc) Small droplets: (<15 microns) Supressed coalescence Clouds with high albedo
Polluted clouds, Suppressed rain, Strong updraft Maritime: Clean, Fast rain, Suppressed updraft 0 o C 0 o C Cloud drop Rain drop Ice crystal Ice precipitation Updraft Cloud drop Rain drop Ice crystal Ice precipitation Updraft
Vertical transport inside and outside stratiform clouds mixing convective mass-flux compensating subsidence cloud base entraining air
Variabilidade interanual e interdecadal da precipitação na Amazônia 1930-1990 1990 Marengo, 2003
Intensity of daily precipitation as a percentage of total amount Climatology of the intensity of daily precipitation as a percentage of total amount in 10 mm/day categories for different temperature regimes, based on 51, 37, and 12 worldwide stations, respectively: blue bars, 3 C to 19 C; pink bars, 19 C to 29 C; dark red bars, 29 C to 35 C. By selection, all stations have the same seasonal mean precipitation amount of 230 ± 5 mm. As temperatures and the associated water-holding capacity of the atmosphere (15) increase, more precipitation falls in heavy (more than 40 mm/day) to extreme (more than 100 mm/day) daily amounts. (Science 302, 1719, 2003)
CCN in biomass burning aerosols: Example of levoglucosan Is a cellulose combustion product at temp>300 o c. It serves as a biomass burning tracer. Is a sugar, highly soluble It is emitted in high quantities.
Large scale cloud formation suppression Terra and Aqua satellite images of the east Amazon basin, 11 August 2002. (A) The clouds (Terra, 10:00 local time) are beginning to form. (B) The clouds (Aqua, 13:00 local time) are fully developed and cover the whole Amazon forest except for the smoke area. The boundary between forest and Cerrado region is marked in white on both images, and the seashore is marked in green. (From Ilan et al., Science March 2004)
Fração de cobertura de nuvens baixas e aerossóis na Amazônia Cloud fraction as function of aerosol optical depth (OD), a measure of the extinction of a beam of light when it passes through a column of atmosphere. The cloud fraction decreases almost linearly with increasing OD. The red and blue curves denote the average of 23 granules in the east and 27 granules in the west of the Amazon, respectively. The estimated error for each point appears as error bars. On average, the cloud fraction decreases to less than 1/8 of the cloud fraction in clean conditions when OD 1. (From Ilan et al., Science March 2004)
Aerosol size distribution in Rondônia 10-fold increase in CCN in Rondônia Dados de A. Vestin e E. Switlicki, Lund, SMOCC 2002
Continental Scale Biomass Burning Plumes
Low Troposphere and Long Distance Transport of PM 2.5 Source: Saulo Freitas and Karla Longo, INPE/CPTEC
Aerosol Optical Thickness in São Paulo Aerosol optical thickness (500 nm) 1.8 1.6 1.4 1.2 1.0 0.8 0.6 0.4 0.2 AOT (500 nm) - São Paulo - daily averages AOT (500 nm) in São Paulo April/02 to Mar/03 0.0 abril maio junho julho agosto setembro outubro novembro dezembro janeiro fevereiro Data April 2002 to March 2003 março Andrea Castanho and Carlos Pires
Aerosol Optical Thickness in São Paulo AOT (500 nm) in São Paulo and fire counts in Amazonia April/02 to Mar/03 1.8 1.6 1.4 AOT (500 nm) - São Paulo - daily average Amazonia hot spots - daily totals (x4000) Aerosol optical thickness (500 nm) 1.2 1.0 0.8 0.6 0.4 0.2 0.0 abril maio junho julho agosto setembro outubro novembro dezembro janeiro fevereiro Data April 2002 to March 2003 março
Modeling the distribution of smoke using high resolution RAMS + GOES fire spots+ emission factors 26-29 26-29 Source: Saulo Freitas and Karla Longo
Effect of smoke aerosols and clouds over the CO2 flux in Amazonia Please see poster from Paulo Henrique Oliveira Relative irradiance (fr)-aerosol optical thickness (AOT)/Dry season Abracos Hill-Rondônia 1.0 34 Air temperature (Tair)- Relative irradiance (fr) Dry season 0.9 32 fr 0.8 0.7 0.6 0.5 0.4 0.0 0.5 1.0 1.5 2.0 2.5 3.0 AOT(nm) Tair ( C) 30 28 26 24 0.6 0.7 0.8 0.9 1.0 fr Net ecosystem exchange of CO 2 (NEE)-Relative irradiance(fr) 10 Annual effects 10 5 5 Net ecosystem exchange of CO 2 (NEE)- Relative irradiance (fr) Dry season 10 10 0 0 0 0 NEE (µmol /m 2 s) -5-10 -15-20 -5-10 -15-20 NEE(µmol /m 2 s) -10-20 -10-20 -25-30 Aerosol effect Cloud effect 0.2 0.4 0.6 0.8 1.0 fr -25-30 -30 Aerosol effect Clouds effect -30 0.2 0.4 0.6 0.8 1.0 1.2 fr
Aerosols,, CCN and clouds final points LBA is finding and studying several processes that are critically important for the hydrological cycle in Amazonia In the wet season, it appears that the vegetation itself controls part of the ingredients: CCN and water vapor In the dry season there is no question now that heavy smoke inhibit cloud formation There are indications that these effects are not constrained only for the Amazon region, but has effects far from Amazonia.??? How this is reflected in the precipitation pattern???