Computationally efficient expressions for the collision efficiency between electrically charged aerosol particles and cloud droplets
Year: 2006
Type: article
Abstract: A multiple factor parametrization is described to permit the efficient calculation of collision efficiency (E) between electrically charged aerosol particles and neutral cloud droplets in numerical models of cloud and climate. The four-parameter representation summarizes the results obtained from a detailed microphysical model ofE, which accounts for the different forces acting on the aerosol in the path of falling cloud droplets. The parametrization's range of validity is for aerosol particle radii of 0.4 to 10 μm, aerosol particle densities of 1 to 2.0 g cm−3, aerosol particle charges from neutral to 100 elementary charges and drop radii from 18.55 to 142 μ m. The parametrization yields values ofE well within an order of magnitude of the detailed model's values, from a dataset of 3978E values. Of these values 95% have modelled to parametrized ratios between 0.5 and 1.5 for aerosol particle sizes ranging between 0.4 and 2.0 μ m, and about 96% in the second size range. This parametrization speeds up the calculation ofE by a factor of ∼103 compared with the original microphysical model, permitting the inclusion of electric charge effects in numerical cloud and climate models. Copyright © 2006 Royal Meteorological Society
DOI: 10.1256/qj.05.125
Authors: S. N. Tripathi, S. Vishnoi, S. Kumar, R. G. Harrison
Institutions: Indian Institute of Technology Kanpur, University of Reading
Language: English
Subfield: Global and Planetary Change
Field: Environmental Science
Domain: Physical Sciences
SDG: Climate action
Open Access status: green
OpenAlex ID: W1965840237