| Abstract |
Recent information suggests that on the global scale, biomass burning is much more extensive and widespread than previously thought. Biomass burning refers to the burning of the world's forests and grasslands and agricultural lands following the harvest for land clearing and land conversion. Biomass burning occurs in the tropics (tropical rain forests and savanna grasslands), in the temperate zone, and in the boreal forest, and is a truly global phenomenon.
Combustion products of biomass burning include carbon dioxide, carbon monoxide, methane, nonmethane hydrocarbons, nitric oxide, nitrous oxide, and atmospheric particulates. Carbon dioxide, methane, and nitrous oxide are important greenhouse gases which impact global climate. Carbon monoxide, methane, nonmethane hydrocarbons, and nitric oxide are chemically active gases that lead to the chemical production of ozone in the lower atmosphere or troposphere. Tropospheric ozone is a pollutant and harmful to living things, including humans.
Recent measurements suggest that biomass burning may be a significant global source of methyl bromide. The bromine released from this compound leads to the chemical destruction of ozone in the upper atmosphere or stratosphere. Unlike tropospheric ozone, stratospheric ozone is very beneficial to living things, including humans, since it absorbs biologically lethal ultraviolet radiation emitted from the Sun. Particulates produced during biomass burning impact the radiation budget of the Earth and, hence, impact global climate. It is thought that as much as 90% of global biomass burning is human-initiated and that such burning is increasing with time. Hence, biomass burning may be an important driver for global atmospheric and climatic change.
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