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.
For Additional Information on Biomass Burning and Global Change:
NASA Fact Sheet: "Biomass Burning: A Hot Issue in Global Change"
Levine, J. S. (Editor), 1991: Global Biomass Burning: Atmospheric,
Climatic, and Biospheric Implications, The MIT Press, Inc., 569 pages.
Levine, J. S., 1992: Climate, The Encyclopedia of Earth System Science (W.
A. Nierenberg, Editor), Academic Press, Inc., Volume 1, page 503-515.
Levine, J. S., 1992: Ozone, Climate, and Global Atmospheric Change, Science
Activities, Vol. 29, No. 1, pp 10-16.
Levine, J. S., W. R. Cofer, D. R. Cahoon, and E. L. Winstead, 1995:
Biomass Burning: A Driver for Global Change, Environmental Science and
Technology, Volume 29, Number 3, pages 120A-125A.
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