Entrainment, extreme inhomogeneous mixing, in the presence of wind shear, and their effect on cloud droplet spectra are investigated. A dynamical model in conjunction with a microphysical model designed to predict evolution of cloud droplet spectra, is employed to perform a two-dimensional simulation of a small nonprecipitating cumulus cloud in the presence of wind shear. / Results show that vortex circulations and penetrative downdrafts are responsible for entrainment of clear air into the cloud structure. Entrainment and mixing are more severe on the downshear side of the cloud leading to a more fragmented structure and often to total dissipation of cloudy air rather than partial dilution as is the case on the upshear side. Mixing followed by uplifting leads to fresh activation of cloud droplets and results in multimodal spectra. In areas where mixing has occurred, the spectra exhibit smaller average radius and larger standard deviation.
Identifer | oai:union.ndltd.org:LACETR/oai:collectionscanada.gc.ca:QMM.61085 |
Date | January 1992 |
Creators | Vaillancourt, Paul |
Publisher | McGill University |
Source Sets | Library and Archives Canada ETDs Repository / Centre d'archives des thèses électroniques de Bibliothèque et Archives Canada |
Language | English |
Detected Language | English |
Type | Electronic Thesis or Dissertation |
Format | application/pdf |
Coverage | Master of Science (Department of Meteorology.) |
Rights | All items in eScholarship@McGill are protected by copyright with all rights reserved unless otherwise indicated. |
Relation | alephsysno: 001284270, proquestno: AAIMM74684, Theses scanned by UMI/ProQuest. |
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