Long-Range Transport of Air Pollution: A Case Study, August 1970

FRANKLIN P. HALL JR. Department of Meteorology, University of Oklahoma, Norman, Okla.

Search for other papers by FRANKLIN P. HALL JR. in
Current site
Google Scholar
PubMed
Close
,
CLAUDE E. DUCHON Department of Meteorology, University of Oklahoma, Norman, Okla.

Search for other papers by CLAUDE E. DUCHON in
Current site
Google Scholar
PubMed
Close
,
LAURENCE G. LEE Department of Meteorology, University of Oklahoma, Norman, Okla.

Search for other papers by LAURENCE G. LEE in
Current site
Google Scholar
PubMed
Close
, and
RICHARD R. HAGAN Department of Meteorology, University of Oklahoma, Norman, Okla.

Search for other papers by RICHARD R. HAGAN in
Current site
Google Scholar
PubMed
Close
Restricted access

Abstract

An air pollution episode during August 1970 over the central United States is examined. By use of surface visibilities and an 850-mb wind trajectory analysis, we observed the pollution to advance as much as 700 mi from the central midwest (source region) into the upper midwest and Great Plains (impact area). A large, nearly stationary high-pressure system over the source region allowed the pollution to accumulate beneath a mid-level subsidence inversion located generally near 700 mb. Southeasterly flow around the backside of the High and the northeasterly flow around a weak Low to the south advected the pollution into the impact area. At times, surface visibilities in parts of the impact area were restricted by haze to as little as 4 mi. Although particulate count data were meager, several stations recorded their highest particulate count of the year during the episode.

Abstract

An air pollution episode during August 1970 over the central United States is examined. By use of surface visibilities and an 850-mb wind trajectory analysis, we observed the pollution to advance as much as 700 mi from the central midwest (source region) into the upper midwest and Great Plains (impact area). A large, nearly stationary high-pressure system over the source region allowed the pollution to accumulate beneath a mid-level subsidence inversion located generally near 700 mb. Southeasterly flow around the backside of the High and the northeasterly flow around a weak Low to the south advected the pollution into the impact area. At times, surface visibilities in parts of the impact area were restricted by haze to as little as 4 mi. Although particulate count data were meager, several stations recorded their highest particulate count of the year during the episode.

Save