Soils: A global sink of atmospheric carbon tetrachloride

Abstract

Analysis of soil gas from the world's major biomes indicates that carbon tetrachloride (CCl 4 ) uptake by soils is a ubiquitous process. The global flux of CCl 4 from the atmosphere to soils was estimated to be 27 ± 21 kilotons per year (Kt yr −1 ), corresponding to a partial atmospheric lifetime of 90 years (yr). The total lifetime of CCl 4 in the atmosphere, taking into account the stratospheric, oceanic and soil sinks is estimated to be 20 yr. The recently identified oceanic and soil sinks of atmospheric CCl 4 suggest that current emission estimates of CCl 4 may be underestimated by ∼60%.