Bergametti G., Marticorena B., Rajot Jean-Louis, Foret G., Alfaro S. C., Laurent B. (2018). Size-resolved dry deposition velocities of dust particles : in situ measurements and parameterizations testing. Journal of Geophysical Research : Atmospheres, 123 (19), p. 11080-11099. ISSN 2169-897X.
Titre du document
Size-resolved dry deposition velocities of dust particles : in situ measurements and parameterizations testing
Bergametti G., Marticorena B., Rajot Jean-Louis, Foret G., Alfaro S. C., Laurent B.
Source
Journal of Geophysical Research : Atmospheres, 2018,
123 (19), p. 11080-11099 ISSN 2169-897X
Bulk and size-resolved particle concentrations were measured at 2.1 and 6.5 m above the soil surface during an intense dust deposition event that occurred in June 2006 in Niger. Bulk concentration measurements were performed using two tapered element oscillating microbalance instruments, and the size-resolved particle concentrations (from 0.3 to 20 mu m) using two optical particle counters. The deposition fluxes derived from the bulk concentrations and those derived from the size-resolved ones are in very good agreement. The largest deposition fluxes are recorded when the dust concentrations are maximal. The temporal evolution of the dust deposition flux follows that of the dust concentration. This is not the case of the dry deposition velocities that are most of the time controlled by the wind friction velocity. The results also show that large particles are strongly sensible to rebound when the wind friction velocity is the highest. Size-resolved dry deposition velocities are compared with the rare measurements of dust deposition velocities over bare sandy soils and are confronted to existing parameterizations of the dry deposition velocity. The parameterization of Zhang and Shao (2014,
Plan de classement
Sciences du milieu [021]
;
Géologie et formations superficielles [064]
