Emissions and Marine Boundary Layer Concentrations of Unregulated Chlorocarbons Measured at Cape Point, South Africa.

Unregulated chlorocarbons, here defined as dichloromethane (CHCl), perchloroethene (CCl), chloroform (CHCl), and methyl chloride (CHCl), are gases not regulated by the Montreal Protocol. While CHCl is the largest contributor of atmospheric chlorine, recent studies have shown that growth in emissions of the less abundant chlorocarbons could pose a significant threat to the recovery of the ozone layer. Despite this, there remain many regions for which no atmospheric monitoring exists, leaving gaps in our understanding of global emissions.

Development of a simplified, cost effective GC-ECD methodology for the sensitive detection of bromoform in the troposphere.

Wherever measurements have been made bromoform was found to be ubiquitous in the surface ocean in pmolar-nmolar concentrations. These measurements show concentrations in coastal regions orders of magnitude higher than in the pelagic oceans. Its atmospheric presence is primarily due to its release from algae and rapid transport to the marine boundary troposphere where it is known to participate in ozone chemistry via photochemical and catalytic pathways.