A Caltech Library Service

Depositional Aspects of Pollutant Behavior in Fog and Intercepted Clouds

Waldman, Jed M. and Hoffmann, Michael R. (1987) Depositional Aspects of Pollutant Behavior in Fog and Intercepted Clouds. In: Sources and Fates of Aquatic Pollutants. Advances in Chemistry. No.216. American Chemical Society , Washington, DC, pp. 79-129. ISBN 9780841209831.

Full text is not posted in this repository. Consult Related URLs below.

Use this Persistent URL to link to this item:


Droplet deposition during fog is shown to play an important role in the removal of anthropogenic pollutants from the atmosphere. Relevant theoretical principles are reviewed. The in-cloud scavenging of aerosols and soluble gases coupled with the small size of fog droplets results in higher chemical concentrations in fog water than in rainwater. In the urban regions of southern California and the southern San Joaquin Valley, fog water chemistry is dominated by sulfate, nitrate, and ammonium ions, which are measured at millimolar levels. The formation of fog is shown to accelerate deposition rates for water-scavenged atmospheric constituents. During stagnation episodes, pollutant removal by ventilation of valley air requires at least 5 days, while the enhancement of deposition by fog formation leads to pollutant lifetimes on the order of 6-12 h. Thus, in an environment characterized by flat, open landscape and low wind speed, droplet sedimentation can be the dominant removal mechanism of pollutants during prolonged stagnation episodes with fog.

Item Type:Book Section
Related URLs:
URLURL TypeDescription
Hoffmann, Michael R.0000-0001-6495-1946
Additional Information:© 1987 American Chemical Society. Received for review May 6, 1986. Accepted October 10, 1986. We are grateful to the California Air Resources Board (CARB) for their financial support (CARB A4-075-32) and their assistance in the field aspects of this project. We appreciate the guidance and assistance provided by the program manager, Eric Fujita. We are also indebted to our colleagues, Daniel Jacob and J. William Munger, who spent many long hours in the field working on aspects of this research.
Funding AgencyGrant Number
California Air Resources BoardCARB A4-075-32
Series Name:Advances in Chemistry
Issue or Number:216
Record Number:CaltechAUTHORS:20150824-142221927
Persistent URL:
Official Citation:Depositional Aspects of Pollutant Behavior in Fog and Intercepted Clouds Jed M. Waldman and Michael R. Hoffmann Sources and Fates of Aquatic Pollutants. June 15, 1987, 79-129 DOI:10.1021/ba-1987-0216.ch004
Usage Policy:No commercial reproduction, distribution, display or performance rights in this work are provided.
ID Code:59858
Deposited By: Ruth Sustaita
Deposited On:25 Aug 2015 17:12
Last Modified:10 Nov 2021 22:26

Repository Staff Only: item control page