Abstract
Abstract. A size dependent parameterization for the removal of aerosol particles by falling rain droplets is developed. Scavenging coefficients are calculated explicitly as a function of aerosol particle size and precipitation intensity including the full interaction of rain droplet size distribution and aerosol particles. The actual parameterization is a simple and accurate three-parameter fit through these pre-calculated scavenging coefficients. The parameterization is applied in the global chemistry transport model TM4 and the importance of below-cloud scavenging relative to other removal mechanisms is investigated for sea salt aerosol. For a full year run (year 2000), we find that below-cloud scavenging accounts for 12% of the total removal of super-micron aerosol. At mid-latitudes of both hemispheres the fractional contribution of below-cloud scavenging to the total removal of super-micron sea salt is about 30% with regional maxima exceeding 50%. Below-cloud scavenging reduces the global average super-micron aerosol lifetime from 2.47 to 2.16 days in our simulations. Despite large uncertainties in precipitation, relative humidity, and water uptake by aerosol particles, we conclude that below cloud scavenging is likely an important sink for super-micron sized sea salt aerosol particles that needs to be included in size-resolved aerosol models.
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
