Radiative forcing calculations for CH{sub 3}Br

Technical Report · Thu Jun 01 04:00:00 EDT 1995

DOI:https://doi.org/10.2172/108173· OSTI ID:108173

Grossman, A S ^[1]; Blass, W E ^[2]; Wuebbles, D J ^[3]

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1. Lawrence Livermore National Lab., CA (United States)
2. Univ. of Tennessee, Knoxville, TN (United States). Dept. of Physics and Astronomy
3. Univ. of Illinois, Urbana, IL (United States). Dept. of Atmospheric Sciences

Methyl Bromide, CH{sub 3}Br, is the major organobromine species in the lower atmosphere and is a primary source of bromine in the stratosphere. It has a lifetime of 1.3 years. The IR methyl bromide spectra in the atmospheric window region, 7--13{mu}, was determined using a well tested Coriolis resonance and {ell}-doubling (and {ell}-resonance) computational system. A radiative forcing value of 0.00493 W/m{sup 2}/ppbv was obtained for CH{sub 3}Br and is approximately linear in the background abundance. This value is about 2 percent of the forcing of CFC-11 and about 278 times the forcing of C0{sub 2}, on a per molecule basis. The radiative forcing calculation is used to estimate the global warming potential (GWP) of CH{sub 3}Br. The results give GWPs for CH{sub 3}Br of the order of 13 for an integration period of 20 years and 4 for an integration period of 100 years (assuming C0{sub 2} = 1, following IPCC [1994]). While CH{sub 3}Br has a GWP which is approximately 25 percent of the GWP of CH{sub 4}, the current emission rates are too low to cause serious atmospheric greenhouse heating effects at this time.

• Research Organization: Lawrence Livermore National Lab., CA (United States)
• Sponsoring Organization: USDOE, Washington, DC (United States); Environmental Protection Agency, Washington, DC (United States)
• DOE Contract Number: W-7405-ENG-48
• OSTI ID: 108173
• Report Number(s): UCRL-ID--121512; ON: DE95017070
• Country of Publication: United States
• Language: English

Related Subjects

54 ENVIRONMENTAL SCIENCES
AIR-WATER INTERACTIONS
ATMOSPHERIC CHEMISTRY
CLIMATIC CHANGE
ENVIRONMENTAL IMPACTS
GREENHOUSE EFFECT
METHYL BROMIDE
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