Modelling future changes in surface ozone: A parameterized approach

Published

Journal Article

This study describes a simple parameterization to estimate regionally averaged changes in surface ozone due to past or future changes in anthropogenic precursor emissions based on results from 14 global chemistry transport models. The method successfully reproduces the results of full simulations with these models. For a given emission scenario it provides the ensemble mean surface ozone change, a regional source attribution for each change, and an estimate of the associated uncertainty as represented by the variation between models. Using the Representative Concentration Pathway (RCP) emission scenarios as an example, we show how regional surface ozone is likely to respond to emission changes by 2050 and how changes in precursor emissions and atmospheric methane contribute to this. Surface ozone changes are substantially smaller than expected with the SRES A1B, A2 and B2 scenarios, with annual global mean reductions of as much as 2 ppb by 2050 vs. increases of 4-6 ppb under SRES, and this reflects the assumptions of more stringent precursor emission controls under the RCP scenarios. We find an average difference of around 5 ppb between the outlying RCP 2.6 and RCP 8.5 scenarios, about 75% of which can be attributed to differences in methane abundance. The study reveals the increasing importance of limiting atmospheric methane growth as emissions of other precursors are controlled, but highlights differences in modelled ozone responses to methane changes of as much as a factor of two, indicating that this remains a major uncertainty in current models. © 2012 Author(s).

Full Text

Duke Authors

Cited Authors

  • Wild, O; Fiore, AM; Shindell, DT; Doherty, RM; Collins, WJ; Dentener, FJ; Schultz, MG; Gong, S; Mackenzie, IA; Zeng, G; Hess, P; Duncan, BN; Bergmann, DJ; Szopa, S; Jonson, JE; Keating, TJ; Zuber, A

Published Date

  • December 1, 2012

Published In

Volume / Issue

  • 12 / 4

Start / End Page

  • 2037 - 2054

Electronic International Standard Serial Number (EISSN)

  • 1680-7324

International Standard Serial Number (ISSN)

  • 1680-7316

Digital Object Identifier (DOI)

  • 10.5194/acp-12-2037-2012

Citation Source

  • Scopus