title: Growth in stratospheric chlorine from short-lived chemicals not controlled by the Montreal Protocol.
abstract: We have developed a chemical mechanism describing the tropospheric degradation of chlorine containing very short-lived substances (VSLS). The scheme was included in a global atmospheric model and used to quantify the stratospheric injection of chlorine from anthropogenic VSLS ( ClyVSLS) between 2005 and 2013. By constraining the model with surface measurements of chloroform (CHCl3), dichloromethane (CH2Cl2), tetrachloroethene (C2Cl4), trichloroethene (C2HCl3), and 1,2-dichloroethane (CH2ClCH2Cl), we infer a 2013 ClyVSLS mixing ratio of 123 parts per trillion (ppt). Stratospheric injection of source gases dominates this supply, accounting for ∼83% of the total. The remainder comes from VSLS-derived organic products, phosgene (COCl2, 7%) and formyl chloride (CHClO, 2%), and also hydrogen chloride (HCl, 8%). Stratospheric ClyVSLS increased by ∼52% between 2005 and 2013, with a mean growth rate of 3.7 ppt Cl/yr. This increase is due to recent and ongoing growth in anthropogenic CH2Cl2-the most abundant chlorinated VSLS not controlled by the Montreal Protocol.
authors: School of Earth and Environment University of Leeds Leeds UK.
authors: R
authors: R
authors: Hossaini
authors: School of Earth and Environment University of Leeds Leeds UK.
authors: M P
authors: MP
authors: Chipperfield
authors: Atmospheric Chemistry and Climate Group Institute of Physical Chemistry Rocasolano, CSIC Madrid Spain.
authors: A
authors: A
authors: Saiz-Lopez
authors: National Centre for Earth Observation, Department of Physics and Astronomy University of Leicester Leicester UK.
authors: J J
authors: JJ
authors: Harrison
authors: Centre for Ocean and Atmospheric Sciences, School of Environmental Sciences University of East Anglia Norwich UK.
authors: R
authors: R
authors: von Glasow
authors: Centre for Ocean and Atmospheric Sciences, School of Environmental SciencesUniversity of East AngliaNorwichUK; Now at Department of ChemistryUniversity of LeicesterLeicesterUK.
authors: R
authors: R
authors: Sommariva
authors: Rosenstiel School of Marine and Atmospheric Science University of Miami Miami Florida USA.
authors: E
authors: E
authors: Atlas
authors: Rosenstiel School of Marine and Atmospheric Science University of Miami Miami Florida USA.
authors: M
authors: M
authors: Navarro
authors: National Ocean and Atmospheric Administration Boulder Colorado USA.
authors: S A
authors: SA
authors: Montzka
authors: National Centre for Atmospheric Science University of Leeds Leeds UK.
authors: W
authors: W
authors: Feng
authors: School of Earth and Environment University of Leeds Leeds UK.
authors: S
authors: S
authors: Dhomse
authors: Scripps Institution of Oceanography University of California San Diego California USA.
authors: C
authors: C
authors: Harth
authors: Scripps Institution of Oceanography University of California San Diego California USA.
authors: J
authors: J
authors: Mühle
authors: Monitoring and Information Technology Department Norwegian Institute for Air Research Kjeller Norway.
authors: C
authors: C
authors: Lunder
authors: Atmospheric Chemistry Research Group, School of Chemistry University of Bristol Bristol UK.
authors: S
authors: S
authors: O'Doherty
authors: Atmospheric Chemistry Research Group, School of Chemistry University of Bristol Bristol UK.
authors: D
authors: 0000-0002-6723-3138
authors: D
authors: Young
authors: Swiss Federal Laboratories for Materials Science and Technology Dübendorf Switzerland.
authors: S
authors: S
authors: Reimann
authors: Swiss Federal Laboratories for Materials Science and Technology Dübendorf Switzerland.
authors: M K
authors: MK
authors: Vollmer
authors: Oceans and Atmosphere Flagship CSIRO Aspendale Victoria Australia.
authors: P B
authors: PB
authors: Krummel
authors: Department of Chemistry and Biochemistry Old Dominion University Norfolk Virginia USA.
authors: P F
authors: 0000-0002-1255-396X
authors: PF
authors: Bernath
keywords: Montreal Protocol; VSLS; dichloromethane; ozone; phosgene; stratosphere