Investigation of warm-cloud microphysics using a multi-component cloud model: Interactive effects of the aerosol spectrum. Master's thesis

Technical Report · Wed Dec 01 00:00:00 EST 1993

OSTI ID:5638603

Zahn, S G

Clouds, especially low, warm, boundary-layer clouds, play an important role in regulating the earth's climate due to their significant contribution to the global albedo. The radiative effects of individual clouds are controlled largely by cloud microstructure, which is itself sensitive to the concentration and spectral distribution of the atmospheric aerosol. Increases in aerosol particle concentrations from anthropogenic activity could result in increased cloud albedo and global cloudiness, increasing the amount of reflected solar radiation. However, the effects of increased aerosol particle concentrations could be offset by the presence of giant or ultragiant aerosol particles. A one-dimensional, multi-component microphysical cloud model has been used to demonstrate the effects of aerosol particle spectral variations on the microstructure of warm clouds. Simulations performed with this model demonstrate that the introduction of increased concentrations of giant aerosol particles has a destabilizing effect on the cloud microstructure. Also, it is shown that warm-cloud microphysical processes modify the aerosol particle spectrum, favoring the generation of the largest sized particles via the collision-coalescence process. These simulations provide further evidence that the effect of aerosol particles on cloud microstructure must be addressed when considering global climate forecasts.

• Research Organization: Air Force Inst. of Tech., Wright-Patterson AFB, OH (United States)
• OSTI ID: 5638603
• Report Number(s): AD-A-270273/6/XAB; AFIT/CI/CIA-93-140
• Resource Relation: Other Information: Master's thesis
• Country of Publication: United States
• Language: English

Related Subjects

54 ENVIRONMENTAL SCIENCES
AEROSOLS
ATMOSPHERIC CHEMISTRY
CLOUDS
MICROSTRUCTURE
EARTH ATMOSPHERE
BOUNDARY LAYERS
CLIMATE MODELS
ALBEDO
ATMOSPHERIC CIRCULATION
METEOROLOGY
SOLAR RADIATION
CHEMISTRY
COLLOIDS
DISPERSIONS
LAYERS
MATHEMATICAL MODELS
RADIATIONS
SOLS
STELLAR RADIATION
540120* - Environment
Atmospheric- Chemicals Monitoring & Transport- (1990-)
540110