Biomass burning is a major source of pollution in the tropical Southern Hemisphere, and fine mode carbonaceous particles are produced by the same combustion processes that emit carbon monoxide (CO). In this paper we examine these emissions with data from the Terra satellite, CO profiles from the Measurement of Pollution in the Troposphere (MOPITT) instrument, and fine-mode aerosol optical depth (AOD) from the Moderate-Resolution Imaging Spectroradiometer (MODIS). The satellite measurements are used in conjunction with calculations from the MOZART chemical transport model to examine the 2003 Southern Hemisphere burning season with particular emphasis on the months of peak fire activity in September and October. Pollutant emissions follow the occurrence of dry season fires, and the temporal variation and spatial distributions of MOPITT CO and MODIS AOD are similar. We examine the outflow from Africa and South America with emphasis on the impact of these emissions on clean remote regions. We present comparisons of MOPITT observations and ground-based interferometer data from Lauder, New Zealand, which indicate that intercontinental transport of biomass burning pollution from Africa often determines the local air quality. The correlation between enhancements of AOD and CO column for distinct biomass burning plumes is very good with correlation coefficients greater than 0.8. We present a method using MOPITT and MODIS data for estimating the emission ratio of aerosol number density to CO concentration which could prove useful as input to modeling studies. We also investigate decay of plumes from African fires following export into the Indian Ocean and compare the MOPITT and MODIS measurements as a way of estimating the regional aerosol lifetime. Vertical transport of biomass burning emissions is also examined using CO profile information. Low-altitude concentrations are very high close to source regions, but further downwind of the continents, vertical mixing takes place and results in more even CO vertical distributions. In regions of significant convection, particularly in the equatorial Indian Ocean, the CO mixing ratio is greater at higher altitudes, indicating vertical transport of biomass burning emissions to the upper troposphere.

https://agupubs.onlinelibrary.wiley.com/doi/pdf/10.1029/2005JD006655

Satellite-observed pollution from Southern Hemisphere biomass burning.

[1] The Southern African Regional Science Initiative (SAFARI 2000) was a major surface, airborne, and spaceborne field campaign carried out in southern Africa in 2000 and 2001 that addressed a broad range of phenomena related to land-atmosphere interactions and the biogeochemical functioning of the southern African system. This paper presents a thematic analysis and integration of the Journal of Geophysical Research SAFARI 2000 Special Issue, presenting key findings of an intensive field campaign over southern Africa in August and September of 2000. The integrating themes deal with surface emissions characterization; airborne characterizations of aerosols and trace gases; regional haze and trace gas characterization; and radiant measurements by surface, aircraft, and remote sensing platforms. Enhanced regional fuel loads associated with the moist La Nina phase of the El Nino-Southern Oscillation (ENSO) cycle produced above average biomass burning emissions, which consequently dominated all other aerosol and trace gas emissions during the dry season. Southward transport of a broad plume of smoke originating in equatorial Africa and exiting off the east coast toward the Indian Ocean (the river of smoke) is attributed to unusual synoptic airflows associated the ENSO phase. New and revised biogenic and pyrogenic emission factors are reported, including a number of previously unreported oxygenated organic compounds and inorganic compounds from biomass combustion. Emission factors are scaled up to regional emission surfaces for biogenic species utilizing species specific and light-dependent emission factors. Fire scar estimates reveal contradictory information on the timing of the peak and extent of the biomass-burning season. Integrated tall stack coordinated measurements (between ground, airborne and remotely sensing platforms) of upwelling and downwelling radiation in massive thick aerosol layers covering much of southern Africa yield consistent estimates of large negative forcing for both surface and top of atmosphere radiative forcing. Radiation calculations are supported by novel information on chemical speciation and internal aerosol particle structure. The overall conclusion is that SAFARI 2000, as an integrating theme, has been able to give significant new insights into the regional scale biogeochemical cycling of southern Africa and contributed in important ways to the validation of remote sensing instruments on board the NASA Terra spacecraft.

/pdf/africa-burning-a-thematic-analysis-of-the-southern-african-nrw6kc83gf.pdf

Africa burning: A thematic analysis of the Southern African Regional Science Initiative (SAFARI 2000)

. Biomass burning is the burning of living and dead vegetation. Ninety percent of all biomass-burning events are thought to be human initiated. Human induced fires are used for a variety of ''applications'' such as agricultural expansion, deforestation, bush control, weed and residue burning, and harvesting practices. Natural fires are grassland and forest fires mainly induced by lightning. It is estimated that 8700 Tg of dry matter/year are burnt each year in total. Emissions from biomass burning include a wide range of gaseous compounds and particles that contribute significantly to the tropospheric budgets on a local, regional, and even global scales. The emission of CO, CH4 and VOC affect the oxidation capacity of the troposphere by reacting with OH radicals, and emissions of nitric oxide and VOC lead to the formation of ozone and other photo oxidants. For a large number of compounds biomass burning is one of the largest single sources in the troposphere, especially in the tropics. Biomass-burning emissions play an important role in the biogeochemical cycles of carbon and nitrogen. Following the first systematic investigations on fire emissions in laboratory experiments in the 1960's, the last 20 years saw an increasing number in studies on biomass-burning emissions in various ecosystems. Recently, our knowledge of the emissions of gaseous compounds in the troposphere from fires has increased considerably. This manuscript is the first of four describing the properties biomass burning emissions. The properties of biomass-burning particles are discussed in part II and III of this review series which have been recently published, and their direct radiative effects are in part IV. This paper focuses on the review of emission ratios and emission rates of carbon monoxide, methane, volatile organics, and nitrogen containing compounds and should not be seen as a review of global emission estimates, even though we discuss the implications of our results on such studies.

/pdf/a-review-of-biomass-burning-emissions-part-i-gaseous-2iz4smw5vl.pdf

A review of biomass burning emissions, part I: gaseous emissions of carbon monoxide, methane, volatile organic compounds, and nitrogen containing compounds

The Southern African Regional Science Initiative (SAFARI 2000) was a major surface, airborne, and spaceborne field campaign carried out in southern Africa in 2000 and 2001 that addressed a broad range of phenomena related to land-atmosphere interactions and the biogeochemical functioning of the southern African system. This paper presents a thematic analysis and integration of the Journal of Geophysical Research SAFARI 2000 Special Issue, presenting key findings of an intensive field campaign over southern Africa in August and September of 2000. The integrating themes deal with surface emissions characterization; airborne characterizations of aerosols and trace gases; regional haze and trace gas characterization; and radiant measurements by surface, aircraft, and remote sensing platforms. Enhanced regional fuel loads associated with the moist La Nina phase of the El Nino-Southern Oscillation (ENSO) cycle produced above average biomass burning emissions, which consequently dominated all other aerosol and trace gas emissions during the dry season. Southward transport of a broad plume of smoke originating in equatorial Africa and exiting off the east coast toward the Indian Ocean (the river of smoke) is attributed to unusual synoptic airflows associated the ENSO phase. New and revised biogenic and pyrogenic emission factors are reported, including a number of previously unreported oxygenated organic compounds and inorganic compounds from biomass combustion. Emission factors are scaled up to regional emission surfaces for biogenic species utilizing species specific and light-dependent emission factors. Fire scar estimates reveal contradictory information on the timing of the peak and extent of the biomass-burning season. Integrated tall stack coordinated measurements (between ground, airborne and remotely sensing platforms) of upwelling and downwelling radiation in massive thick aerosol layers covering much of southern Africa yield consistent estimates of large negative forcing for both surface and top of atmosphere radiative forcing. Radiation calculations are supported by novel information on chemical speciation and internal aerosol particle structure. The overall conclusion is that SAFARI 2000, as an integrating theme, has been able to give significant new insights into the regional scale biogeochemical cycling of southern Africa and contributed in important ways to the validation of remote sensing instruments on board the NASA Terra spacecraft.

Africa burning: A thematic analysis of the Southern African Regional Science Initiative (SAFARI 2000) : SAFARI 2000-Southern African Regional Science Initiative

Received 24 October 2004; revised 19 January 2005; accepted 4 March 2005; published 1 June 2005. [1] We present the first observations of tropospheric carbon monoxide (CO) by the Atmospheric Infrared Sounder (AIRS) onboard NASA’s Aqua satellite. AIRS daily coverage of 70% of the planet represents a significant evolutionary advance in satellite trace gas remote sensing. Tropospheric CO abundances are retrieved from AIRS 4.55 mm spectral region using the full AIRS retrieval algorithm run in a research mode. The presented AIRS daily global CO maps from 22– 29 September 2002 show large-scale, long-range transport of CO from anthropogenic and natural sources, most notably from biomass burning. The sequence of daily maps reveal CO advection from Brazil to the South Atlantic in qualitative agreement with previous observations. Forward trajectory analysis confirms this scenario and indicates much longer range transport into the southern Indian Ocean. Preliminary comparisons to in situ aircraft profiles indicate AIRS CO retrievals are approaching the 15% accuracy target set by pre-launch simulations. Citation: McMillan, W. W., C. Barnet, L. Strow, M. T. Chahine, M. L. McCourt, J. X. Warner, P. C. Novelli, S. Korontzi, E. S. Maddy, and S. Datta (2005), Daily global maps of carbon monoxide from NASA’s Atmospheric Infrared Sounder, Geophys. Res. Lett., 32, L11801, doi:10.1029/ 2004GL021821.

http://www.atmos.berkeley.edu/~inez/MSRI-NCAR_CarbonDA/papers/Bibliography%20-%20Miller/GRL%2032,%20%20L11081%20(2005)%20-%20Daily%20global%20CO%20maps%20from%20AIRS.pdf

Daily global maps of carbon monoxide from NASA's Atmospheric Infrared Sounder

[1] Episodes of regionally extensive haze were observed over southern African during the dry season intensive of the Southern African Regional Science Initiative (SAFARI 2000). Several case studies of southern African haze layers were examined and characterized in terms of physical structure as they exited off of the eastern coastal region of southern Africa. In situ observations of aerosols and trace gases and their physical and chemical characteristics were collected on board South African Weather Service Aerocommander research aircraft. Haze structure, based on these measurements, is examined as it varies with synoptic type. Despite strong differences in the observed ENSO regime between SAFARI 2000 and that observed during the Southern African Fire-Atmosphere Research Initiative (SAFARI-92) and their respective aerosol accumulation mechanisms (col Rrgions/weak anticyclones versus strong anticyclones), a surprising degree of consistency in the observed vertical structure of the lower troposphere was found in southern Africa. INDEX TERMS: 0305 Atmospheric Composition and Structure: Aerosols and particles (0345, 4801); 0345 Atmospheric Composition and Structure: Pollution—urban and regional (0305); 0365 Atmospheric Composition and Structure: Troposphere—composition and chemistry; 0368 Atmospheric Composition and Structure: Troposphere—constituent transport and chemistry; KEYWORDS: haze layers, synoptic circulations, ENSO

https://agupubs.onlinelibrary.wiley.com/doi/pdf/10.1029/2002JD003237

Haze layer characterization and associated meteorological controls along the eastern coastal region of southern Africa

Retrieved tropospheric carbon monoxide (CO) column densities are presented for more than 9000 spectra obtained by the University of Wisconsin-Madison (UWis) Scanning High-Resolution Interferometer Sounder (SHIS) during a flight on the NASA ER-2 on 7 September 2000 as part of the Southern African Regional Science Initiative (SAFARI 2000) dry season field campaign. Enhancements in tropospheric column CO were detected in the vicinity of a controlled biomass burn in the Timbavati Game Reserve in northeastern South Africa and over the edge of the river of smoke in south central Mozambique. Relatively clean air was observed over the far southern coast of Mozambique. Quantitative comparisons are presented with in situ measurements from five different instruments flying on two other aircraft: the University of Washington Convair-580 (CV) and the South African Aerocommander JRB in the vicinity of the Timbavati fire. Measured tropospheric CO columns (extrapolated from 337 to 100 mb) of 2.1 x 10(exp 18) per square centimeter in background air and up to 1.5 x 10(exp 19) per square centimeter in the smoke plume agree well with SHIS retrieved tropospheric CO columns of (2.3 plus or minus 0.25) x 10(exp 18) per square centimeter over background air near the fire and (1.5 plus or minus 0.35) x 10(exp 19) per square centimeter over the smoke plume. Qualitative comparisons are presented with three other in situ CO profiles obtained by the South African JRA aircraft over Mozambique and northern South Africa showing the influence of the river of smoke.

/pdf/tropospheric-carbon-monoxide-measurements-from-the-scanning-5buf7ni067.pdf

Tropospheric Carbon Monoxide Measurements from the Scanning High-resolution Interferometer Sounder on 7 September 2000 in Southern Africa during SAFARI 2000

D. C. Stein

Papers

Haze layer characterization and associated meteorological controls along the eastern coastal region of southern Africa

Tropospheric Carbon Monoxide Measurements from the Scanning High-resolution Interferometer Sounder on 7 September 2000 in Southern Africa during SAFARI 2000

Preliminary results of dry-season trace gas and aerosol measurements over the Kalahari region during SAFARI 2000