Carbon biomass burning

Human interaction with the global cycle is most evident in the movement of the element carbon. The burning of biomass, coal, oil, and natural gas to generate heat and electricity has released carbon to the atmosphere and oceans in the forms of CO2 and carbonate. Because of the relatively slow... 

Concerns over atmospheric methane as a greenhouse gas and the large contribution of biomethanogenesis as a source of this gas make it important to determine the relative significance of various components of this activity. A recent paper (8) summarized estimates (28-30) of source fluxes of atmospheric methane based on several carbon isotopic studies and presented new data on natural sources and biomass burning. These data (Table III) show that of a total flux of 594 million tons (Tg) per year, 83% is produced via biomethanogenesis from a combination of natural (42%) and anthropogenic (41%) sources. 

Tropical forests and savannas are the primary source of C emissions that originate from biomass burning (73, 75). However, temperate forests are also sources of atmospheric carbon. Harmon et al. (77) reported that conversion of primary temperate forests to younger, second-growth forests lead to increases in atmospheric CO2 levels, due to losses in long-term carbon storage within these forests. They ascertained that timber exploitation of 5 million hectares of primaiy forests in the Pacific Northwest of North America during the past century has resulted in the addition of 1,500 Tg of C to the atmosphere. 

The role of carbon dioxide in the Earth s radiation budget merits this interest in atmospheric CO2. There are, however, other changes of importance. The atmospheric methane concentration is increasing, probably as a result of increasing cattle populations, rice production, and biomass burning (Crutzen, 1983). Increasing methane concentrations are important because of the role it plays in stratospheric and... 

Seiler, W. and Crutzen, P. J. (1980). Estimates of gross and net fluxes of carbon between the biosphere and the atmosphere from biomass burning. Climat. Change 2, 226-247. 

Some component of the terrestrial POM must be extremely nonreactive to enable a higher burial efficiency as compared to autochthonous POM. A possible candidate for this nonreactive terrestrial POM is black carbon. This material is a carbon-rich residue produced by biomass burning and fossil fuel combustion. Some black carbon also appears to be derived from graphite weathered from rocks. It is widely distributed in marine sediments and possibly carried to the open ocean via aeolian transport. 

Carbon monoxide is an important trace gas, which has a mean residence time of about two months and a mean concentration of the order of 0.1 ppm. The principal sources of CO are (1) oxidation of methane and other higher hydrocarbons, (2) biomass burning, (3) traffic, industry and domestic heating, (4) oceans, and (5)... 

Plumes from biomass burning can also have unique signatures. For example, organics, ammonium, potassium, sodium, nitrate, nitrite, sulfate, chloride, phosphate, elemental carbon, and the anions of organic acids (formate, acetate, oxalate, etc.) have all been measured in particles in the plumes from burning vegetation (e.g., see Cofer et al., 1988 Andreae et al., 1988 and Artaxo et al., 1994). 

Blake NJ, Blake DR, Sive BC, Chen T-Y, Rowland FS, Collins Jr. JE, Sachse GW, Anderson BE (1996) Biomass Burning Emissions and Vertical Distribution of Atmospheric Methyl Halides and Other Reduced Carbon Gases in the South Atlantic Region. J Geophys Res 101 24151... 

Lobert, J. M., D. H. Scharffe, W. M. Hao, T. A. Kuhlbusch, P. Warneck, and P. J. Crutzen. 1991. Experimental evaluation of biomass burning emissions Nitrogen and carbon containing compounds. In Global Biomass Burning Atmospheric, Climatic and Biospheric Implications (J. S. Levine, Ed.). MIT Press, Cambridge, MA. 

Schmidt, M. W. I., Skjemstad, J. O., and Jager, C. (2002). Carbon isotope geochemistry and nanomorphology of soil black carbon Black chernozemic soils in central Europe originate from ancient biomass burning, Global Biogeochem. Cycles 16, Art. No. 1123. 

The product of incomplete burning of various fuels (mainly fossil fuel and biomass burning) is called black carbon (BC), made up of soot and smoke aerosol that absorbs short-wave radiation. Estimates of direct RF due to BC and organic matter (OM) have led to values in the interval from +0.16 Wm-2 to +0.42 W m-2, and total absorbed radiation within 0.56 Wm 2-2 Wm-2 (the parameter BC + OM is the soot component that appears as a result of fossil fuel burning). About 10% (by mass) BC constitutes aerosol formed in biomass burning, for which RF values were obtained from 0.16Wm-2 to -0.74Wm-2, whereas the radiation absorbed by aerosol varies within 0.75 Wm-2 to 2Wm"2. 

The contribution of savannah fires exceeds 40% of the global level of biomass burning as a result of which the atmosphere receives minor gas components, such as non-methane hydrocarbons, carbon monoxide, methane, etc., as well as aerosols. According to available estimates for the period 1975-1980, 40%-70% of savannahs were burnt every year, about 6% of such fires took place in Africa. In 1990 about 2 1091 of vegetable biomass were burnt, and as a result 145TgCO got into the atmosphere, which constituted about 30% of anthropogenic CO emissions. 

Choi S.-D. and Chang Y.-S. (2006). Carbon monoxide monitoring in Northeast Asia using MOPITT Effects of biomass burning and regional pollution in April 2000. Atmospheric Environment, 40(4), 686-697. 

Carbon monoxide (CO) strongly influences the concentration of the radical OH in the tropical atmosphere. CO oxidation can lead to either production or destruction of ozone, depending on the NOx mixing ratio. Tropical soils are either a sink or a weak source of CO, where photochemical oxidation of methane and other hydrocarbons and biomass burning emissions are the predominant CO sources. 

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