Johnson, C. E., Collins, W. J., Stevenson, D. S., Derwent, R. G.

Journal of Geophysical Research: Atmospheres

Published date August 1, 1999

Relative roles of climate and emissions changes on future tropospheric oxidant concentrations

  • Drives a lagrangian chemistry-transport model (STOCHEM) with 'meteorology derived from a slab' ocean general circulation model for conditions appropriate to the present-day and at double CO2, and with emission scenarios appropriate for present day conditions and for the year 2075
  • Results show conclusively that the effect of including the predicted changes to future climate is to reduce the simulated tropospheric ozone concentrations
  • Finds the response of global tropospheric ozone in the period 1990–2075 was an increase of 6.4 ppb when both climate and emissions changes were included, compared to an increase of 10.3 ppb when only emissions changes were considered
  • Finds the difference is mainly due to water vapor and temperature increases, together with some dynamical effects
  • States there are considerable changes to other tropospheric oxidants, with OH, HO2, and H2O2 all increasing considerably in response to climate changes