Mean concentration and flux profiles for chemically reactive species in the atmospheric surface layer

Abstract

We use Monin-Obukhov similarity theory to study the vertical structure of turbulent fluxes and concentrations of reactive species in the surface layer. A surface layer flux-gradient relation that includes first and second-order chemical reactions is derived from the flux budgets. The theory is then applied specifically to the O3-NO-NO2 photochemical reaction triad. In this case it is found that the non-reactive flux-gradient relation usually suffices, but that chemical reactions can seriously alter the surface layer turbulent flux and mean concentration profiles. It is demonstrated that six observations of fluxes or concentrations are necessary to determine the surface fluxes when reactions are significant. Significant deviations from the predicted nonreactive flux are found to be quite plausible for NOx levels characteristic of moderately polluted air. © 1983.