Visibility in California

Journal Article · Mon Feb 01 00:00:00 EST 1982 · J. Air Pollut. Control Assoc.; (United States)

DOI:https://doi.org/10.1080/00022470.1982.10465385· OSTI ID:5656956

Trijonis, J

A comprehensive study is conducted of visibility in California using prevailing visibility measurements at 67 weather stations in conjunction with data on particulate concentrations and meteorology. The weather station visibility data, when handled with special techniques that account for the nature of visibility reporting practices, prove to be of very good quality for the purposes of most of the analyses that are attempted. It is found that the most important meteorological parameters with respect to visibility are relative humidity, temperature, and special weather events (especially fog). A detailed isopleth map of visibility within California, when compared with earlier work on nationwide visibility, reveals that California experiences far more severe and complex spatial gradients in visibility than those observed anywhere else in the U.S. Two major pockets of heavy man-made visibility impact in California are the Los Angeles basin and the San Joaquin Valley. The spatial, seasonal, and diurnal patterns of visibility are found to be readily explainable in terms of corresponding patterns in emissions, air quality, and meteorology. Regression analyses relating visibility to relative humidity and aerosol concentrations produce high levels of correlation and physically reasonable regression coefficients; these analyses indicate that secondary aerosols are major contributors to visibility reduction in California. An analysis of long-term visibility trends from 1949 to 1976 reveals several interesting features in historical visibility changes for California.

• Research Organization: Santa Fe Research Corp., NM
• OSTI ID: 5656956
• Journal Information: J. Air Pollut. Control Assoc.; (United States), Vol. 32:2
• Country of Publication: United States
• Language: English

Related Subjects

54 ENVIRONMENTAL SCIENCES
CALIFORNIA
AIR QUALITY
SMOG
ENVIRONMENTAL EFFECTS
AEROSOLS
DAILY VARIATIONS
FOG
METEOROLOGY
PARTICULATES
SEASONAL VARIATIONS
VISIBILITY
COLLOIDS
DISPERSIONS
ENVIRONMENTAL QUALITY
FEDERAL REGION IX
NORTH AMERICA
PARTICLES
SOLS
USA
VARIATIONS
500200* - Environment
Atmospheric- Chemicals Monitoring & Transport- (-1989)