Author: Elizabeth Anne StonePublisher:
ISBN:
Category :
Languages : en
Pages : 279
Book Description
Source Apportionment of Carbonaceous Aerosol in Different Regions of the World
Author: Elizabeth Anne StonePublisher:
ISBN:
Category :
Languages : en
Pages : 279
Book Description
A Comprehensive Characterization of Carbonaceous Aerosols in St. Louis, Missouri
Author: Min-Suk BaeSampling, Analysis, and Source-apportionment of Ambient Carbonaceous Aerosols
Author: R. SubramanianCarbonaceous Aerosol
Author: András GelencsérPublisher: Springer
ISBN: 9789048167401
Category : Science
Languages : en
Pages : 0
Book Description
The concept of carbonaceous aerosol has only recently emerged from atmospheric pollution studies; even standard nomenclature and terminology are still unsettled. This monograph is the first to offer comprehensive coverage of the nature and atmospheric role of carbonaceous aerosol particles. Atmospheric chemists, physicists, meteorologists, and modellers will find this a thought-inspiring and sometimes provocative overview of all global phenomena affected by or related to carbonaceous aerosol.
Source Apportionment of Carbonaceous Aerosols Using Integrated Multi-variant and Source Tracer Techniques and a Unique Molecular Marker Data Set
Author: James J. SchauerPublisher:
ISBN:
Category : Aerosols
Languages : en
Pages : 212
Book Description
Characterization and Source Apportionment of Carbonaceous Aerosols in China
Author: Investigation of Carbonaceous Aerosol Optical Properties to Understand Impacts on Air Quality and Composition
Author: Michael Robert OlsonPublisher:
ISBN:
Category :
Languages : en
Pages : 0
Book Description
The optical properties of carbonaceous aerosols were investigated to understand the impact source emissions and ambient particulate matter (PM) have on atmospheric radiative forcing. Black carbon (BC) is a strong absorber of visible light and contributes highly to atmospheric radiative forcing, therefore it is important to link BC properties to combustion emission sources. Brown carbon (BrC) is poorly understood and may be an important contributor to both positive and negative radiative forcing. The research investigates these primary knowledge gaps. The optical properties of carbonaceous aerosols were investigated to understand the impact source emissions and ambient particulate matter (PM) have on atmospheric radiative forcing. Black carbon (BC) is a strong absorber of visible light and contributes highly to atmospheric radiative forcing, therefore it is important to link BC properties to combustion emission sources. Brown carbon (BrC) is poorly understood and may be an important contributor to both positive and negative radiative forcing. The research investigates these primary knowledge gaps. Multiple methods were developed and applied to quantify the mass absorption cross-section (MAC) at multiple wavelengths of source and ambient samples. The MAC of BC was determined to be approximately 7.5 m2g−1 at 520nm. However, the MAC was highly variable with OC fraction and wavelength. The BrC MAC was similar for all sources, with the highest absorption in the UV at 370nm; the MAC quickly decreases at larger wavelengths. In the UV, the light absorption by BrC could exceed BC contribution by over 100 times, but only when the OC fraction is large (>90%) as compared to the total carbon. BrC was investigated by measuring the light absorption of solvent extracted fractions in water, dichloromethane, and methanol. Source emissions exhibited greater light absorption in methanol extractions as compared to water and DCM extracts. The BrC MAC was 2.4 to 3.7 m2g−1 at 370nm in methanol. Ambient samples showed similar MACs for the water and methanol extracts. Dichloromethane extracts did not have a significant light absorption characteristics for ambient samples. BrC and BC were measured in Beijing, China. Both were reduced significantly when restrictive air pollution controls were put in place. The industrial regions south and east of Beijing were the highest contributors to ambient BrC and BC. The controls reduced BrC more than BC as compared to observations during the regions heating period. Using the color characteristics of ambient PM, a model was developed to estimate elemental and organic carbon (EC/OC). The method will allow fast and cost effective quantification of PM composition in combination with large climate and health studies, especially in the developing world.
Source Apportionment of Carbonaceous Aerosol
Author: Radiocarbon-supported Source Apportionment of Carbonaceous Aerosols
Author: Nolwenn PerronAirborne Measurements of Carbonaceous Aerosols in Southern Africa During the Dry, Biomass Burning Season
Author: Publisher:
ISBN:
Category :
Languages : en
Pages : 5
Book Description
Particulate matter collected aboard the University of Washington's Convair-580 research aircraft over southern Africa during the dry, biomass burning season was analyzed for total carbon, organic carbon, and black carbon contents using thermal and optical methods. Samples were collected in smoke plumes of burning savanna and in regional haze. A known artifact, produced by the adsorption of organic gases on the quartz filter substrates used to collect the particulate matter samples, comprised a significant portion of the total carbon collected. Consequently, conclusions derived from the data are greatly dependent on whether or not organic carbon concentrations are corrected for this artifact. For example, the estimated aerosol co-albedo (1 - single scattering albedo), which is a measure of aerosol absorption, of the biomass smoke samples is 60 percent larger using corrected organic carbon concentrations. Thus, the corrected data imply that the biomass smoke is 60 percent more absorbing than do the uncorrected data. The black carbon to (corrected) organic carbon mass ratio (BC/OC) of smoke plume samples (0.18/2610.06) is lower than that of samples collected in the regional haze (0.25/2610.08). The difference may be due to mixing of biomass smoke with background air characterized by a higher BC/OC ratio. A simple source apportionment indicates that biomass smoke contributes about three-quarters of the aerosol burden in the regional haze, while other sources (e.g., fossil fuel burning) contribute the remainder.