Air Pollution and Warm Fog Modification.

Abstract

Through a series of simple calculations on monodispersed fogs, it is shown that atmospheric air pollutants in the form of cloud condensation nuclei (CCN) contribute to a lowering of the visibility and, thereby, seriously inhibit the visibility-improving capability of some evaporation techniques of warm fog modification. In extreme pollution, where the CCN counts are in excess of 1000/cc and the initial visibility is, therefore, very low, those techniques that only depress relative humidity a few percent, for example, hygroscopic particle seeding, could be rendered almost powerless in improving visibility to practically useful levels. Those fog dispersal techniques that of practical necessity generally depress the relative humidity by more than five % such as thermal fog dispersal, are not so seriously hampered by atmospheric pollutants. (Modified author abstract)

Document Details

Document Type
Technical Report
Publication Date
Jun 25, 1974
Accession Number
AD0786454

Entities

People

  • Alan I. Weinstein

Organizations

  • Air Force Cambridge Research Laboratories

Tags

DTIC Thesaurus Topics

  • Abstracts
  • Air Pollutants
  • Air Pollution
  • Condensation
  • Condensation Nuclei
  • Evaporation
  • Humidity
  • Isothermal Processes
  • Particles
  • Phase Transformations
  • Thermodynamic Processes
  • Visibility

Fields of Study

  • Environmental science

Readers

  • Aerosol Science/Aerosol Physics
  • Mathematics or Statistics
  • Systems Analysis and Design