Atmospheric Trace Gases in the Southern Hemisphere

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“…The same conclusion was drawn earlier by Seiler (1974) based on a 3-month continuous CO record measured on board RS "Shackleton" over the South Atlantic Ocean at 40-63's which showed even smaller variations of the CO mixing ratios in air. The assumption of a uniform distribution of CO in unpolluted southern hemispheric air is in agreement with the observation of almost constant CO mixing ratios over large areas of the Atlantic (Seiler, 1976) and Pacific Oceans (Wilkniss et al, 1973) and is also consistent with the observation of constant CO mixing ratios with altitude in the southern hemispheric troposphere south of 20' S (Seiler and Fishman,198 1). The lack of short-term variations of the CO mixing ratios and the short residence time of CO with values varying between 1 and 3 months also indicates that the sources and sinks responsible for the observed seasonal variation at Cape Point must be widespread and cannot be of local or regional origin.…”

“…Measurements of the global distribution of CO have been carried out repeatedly during the last 12 years by different groups (Seiler, 1974; Wilkniss et al, 1973; Heidt et al, 1980; Seiler and Fishman, 1981). However, the present data basis is still too limited to give reliable information on the possible , 4 temporal change of CO mixing ratios in the troposphere.…”

Infrared Measurement of Fluorocarbons, Carbon Tetrachloride, Carbonyl Sulfide, And Other Atmospheric Trace Gases

“…Measurements by Lovelock, et al, 1 and by Wilkness, et al, 8 in 1973 averaged about 7 X 10~n atm. In 1974, Lovelock reported amounts of CCI4 between 1.4 X 10~1 0 atm.…”

Radon daughter disequilibria in the lower marine boundary layer

“…(Downey et al, 1990). Estimates of radon concentration at sea level, based on daughter measurements, such as those of Wilkniss et al (1973) or Lambert et al (1970), may therefore be in error by as much as a factor of 10 unless allowance is made for particle concentration. Even then under conditions typical of air streams with very long marine trajectories, accuracies better than 30% are not possible.…”

“…After a period of about 2 h, the activity of the daughters is virtually the same as that of the radon, unless there are loss mechanisms other than radioactive decay. Thus, radon can be measured directly (Whittlestone, 1985b), which is complex, or estimated by measuring radon daughter concentrations and either assuming equilibrium or estimating the degree of disequilibrium of the daughters with respect to radon (Larson, 1973;Wilkniss et al, 1973;Lambert et al, 1970).…”