Ig. Mckendry et J. Lundgren, Tropospheric layering of ozone in regions of urbanized complex and/or coastal terrain: a review, PROG P GEO, 24(3), 2000, pp. 329-354
Exchange of pollutants between the atmospheric boundary layer and free trop
osphere is an important (yet often neglected) process that tends to produce
distinct layers of pollution in the lower troposphere. These layers repres
ent a potential sink for pollutants from the boundary layer, have the poten
tial to be mixed to ground and likely influence tropospheric chemistry and
the global climate system. Factors influencing the vertical distribution of
ozone in the troposphere are outlined as a prelude to a more specific disc
ussion of elevated layers and myriad meteorological processes responsible f
or their development. Evidence from a range of geographical settings sugges
ts that these phenomena are ubiquitous. A rich data set from the Lower Fras
er Valley, British Columbia, is used to provide an inventory of layer struc
tures and to highlight their diverse origins and histories. Approaches used
to assess the impact of down-mixing of pollutants from elevated layers on
ground-level concentrations of ozone are outlined and future research prior
ities recommended.