Measurements of atmospheric methyl bromide and bromoform
- Author(s): Cicerone, RJ
- Heidt, LE
- Pollock, WH
- et al.
Published Web Locationhttps://doi.org/10.1029/JD093iD04p03745
We have measured gaseous methyl bromide (CH3Br) and bromoform (CHBr3) in air samples that were gathered approximately weekly from five ground-level sites: Point Barrow, Alaska; Mauna Loa Observatory and Cape Kumukahi, Hawaii; Matatula, Samoa; and Kaitorete Spit, New Zealand. Approximately 750 samples have been analyzed for CH3Br between January 1985 and October 1987 and 990 samples have been analyzed for CHBr3 between early 1984 and September 1987, all by gas chromatography/mass spectometry. Methyl bromide concentrations are typically 10-11 parts per trillion (ppt) by volume; there are no clear indications of temporal increases. Bromoform concentrations are typically 2-3 ppt, but large seasonal variations are seen at Point Barrow. -Authors