Measurements of sulphate dry deposition over flat terrain in Central Spain

Abstract

Measurements of sulphate dry deposition were carried out in a flat terrain over low vegetation in July 1993. Turbulent parameters, fluxes of momentum and sensible heat were calculated using the eddy-correlation technique. Sulphate aerosols were simultaneously collected at 4 levels during a sampling time of approximately 2-h. In order to characterize the size of sulphate aerosols, concurrent measurements of aerosol spectra measured with a laser spectrometer were also performed. Deposition velocities and fluxes were calculated by the gradient method under the assumption that the eddy diffusivity of sensible heat was equivalent to Kc. The median value of dry deposition velocities was 1.13 cm·s-1. The influence of atmospheric stability on sulphate dry deposition fluxes is presented and discussed.