Mixing of dust aerosols into a mesoscale convective system Generation, filtering and possible feedbacks on ice anvils

During the second Specific Observing Period (SOP) of the African Monsoon Multidisplinary Analyses (AMMA) campaign, several intense mesoscale convective systems (MCS) developed over Niger. An examination of a particular convective storm simulated with a mesoscale model near Banizoumbou, Niger, on 1 J...

Full description

Saved in:
Bibliographic Details
Published in:Atmospheric research 2010-05, Vol.96 (2-3), p.302-314
Main Authors: TULET, P, CRAHAN-KAKU, K, LERICHE, M, AOUIZERATS, B, CRUMEYROLLE, S
Format: Article
Language:English
Subjects:
Atmospheric and Oceanic Physics
Earth, ocean, space
Exact sciences and technology
External geophysics
Meteorology
Particles and aerosols
Physics
Water in the atmosphere (humidity, clouds, evaporation, precipitation)
Online Access:Get full text
Tags: Add Tag
No Tags, Be the first to tag this record!
Description
Summary:During the second Specific Observing Period (SOP) of the African Monsoon Multidisplinary Analyses (AMMA) campaign, several intense mesoscale convective systems (MCS) developed over Niger. An examination of a particular convective storm simulated with a mesoscale model near Banizoumbou, Niger, on 1 July, 2006, shows that this MCS generates a strong emission of dust particles at the leading edge of its density current. A fraction of these dust aerosols are uplifted by the convective core of the system and redistributed by aqueous processes. Aerosol impaction scavenging is the main process by which particles are deposited within the mesoscale convective system. However, small particles (smaller than 1 μm) that are not efficiently scavenged, are able to reach the upper troposphere at a concentration of 6 particles per cm3. This suggests that deep convection over semi-arid regions is able to create its own ice nuclei in high concentrations. This leads to the question: can deep convection over semi-arid regions affect particular ice properties such as ice anvil extension or induce possible feedbacks of dust on precipitation through ice sedimentation?
ISSN:0169-8095
1873-2895
DOI:10.1016/j.atmosres.2009.09.011