Open AccessRole of convection in determining the budget of odd hydrogen in the upper troposphere
Author(s) -
Collins W. J.,
Stevenson D. S.,
Johnson C. E.,
Derwent R. G.
Publication year - 1999
Publication title -
journal of geophysical research: atmospheres
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.67
H-Index - 298
eISSN - 2156-2202
pISSN - 0148-0227
DOI - 10.1029/1999jd900143
Subject(s) - troposphere , isoprene , convection , atmospheric sciences , atmospheric convection , environmental science , chemical transport model , formaldehyde , atmospheric chemistry , meteorology , ozone , chemistry , geology , physics , organic chemistry , copolymer , polymer
This paper presents a model study of the changes in upper tropospheric HO x ( = OH + HO 2 ) due to upward convective transport of surface pollutants. The model used is a three‐dimensional global Lagrangian tropospheric chemistry transport model of 70 chemical species and 150 reactions including nonmethane hydrocarbon chemistry. It is driven by meteorological data from the U.K. Meterological Office with a 6 hour time resolution. We find that the effect of convection is to increase upper tropospheric (300–200 hPa) HO x globally by over 50%. The effect is greatest over the tropical continents where convection and VOC emissions from vegetation are colocated. The convection of isoprene, and hydroperoxides has the greatest effect. Convecting formaldehyde and acetone has a lesser effect. The contribution from isoprene depends more on the convection of its degradation products than the convection of isoprene itself. The upper tropospheric HO x budget is shown to be very sensitive to the model implementation of convective wet deposition.