FY 1988

A new transient tracer: Measured vertical distribution of CCl₂FCClF₂ (F113) in the North Pacific subarctic gyre

Wisegarver, D.P., and R.H. Gammon

Geophys. Res. Lett., 15(2), doi: 10.1029/GL015i002p00188, 188–191 (1988)

The first quantitative marine measurements of trichlorotrifluoroethane (F-113) were made in the North Pacific subarctic gyre in July of 1986, using a modification of the analytical procedure developed for the transient tracers F-11 and F-12 (Gammon et al., 1982; Wisegarver and Cline, 1985). The measured mixed layer concentration was 0.29 ± 0.2 pM/L; the corresponding atmospheric mixing ratio was 35 ± 1 pptv (Rasmussen scale).

Below a subsurface maximum both F-11 and F-113 were found to fall off exponentially with increasing depth, F-113 reaching effective blank levels first. The significance of adding F-113 to the existing suite of measurable oceanic transient tracers rests in the possibility of age-dating water masses by their (F-113/F-11) ratio with near annual resolution for the period since 1977.