Vertical redistribution of a pollutant tracer due to cumulus convection

Thesis/Dissertation · Sat Jan 01 04:00:00 EST 1983

OSTI ID:6218599

Ritter, J A

A formalism is presented that incorporates the physical processes responsible for the vertical redistribution of a conservative pollutant tracer due to a convective cloud field and demonstrates that the cloud venting process should not be neglected in regional-scale modeling. Two modeling approaches are presented which, although both are based on the framework common to the works of Ogura and Cho (1973) and Johnson (1975), differ in the manner in which the cloud field is forced. The first approach (called an implicit model) is adapted from Johnson (1975) wherein the cloud forcing functions are determined from synoptic-scale heat and moisture budgets. The second model (called an explicit model) obtains the forcing functions in a unique way by explicitly incorporating the vertical distribution of cumulus cloud cover, thereby incorporating the influences of subsynoptic-scale phenomena. By comparing the results of these two approaches, the role of subsynoptic-scale phenomena in determining the vertical pollutant transport due to cumulus convection can be assessed. The results of this study show that the subscale effects of cumulus clouds can be included into a regional-scale transport model in a realistic way. It is also shown that the concentration increase in the cloud layer due to the venting action of cumulus clouds can be frequently as important as, if not more important than the in-situ production of some species and should therefore not be neglected in regional-scale transport models.

• OSTI ID: 6218599
• Country of Publication: United States
• Language: English

Related Subjects

500200* -- Environment
Atmospheric-- Chemicals Monitoring & Transport-- (-1989)
54 ENVIRONMENTAL SCIENCES
AIR POLLUTION
CLOUD COVER
CONVECTION
ENERGY TRANSFER
ENVIRONMENTAL TRANSPORT
HEAT TRANSFER
MASS TRANSFER
MATHEMATICAL MODELS
POLLUTANTS
POLLUTION