Development of a Meteorologically Controlled Agricultural Burning Program

Abstract

As an extension of strong policy against open burning, the Bay Area Air Pollution Control District, in 1967, placed the previously unregulated burning of deciduous fruit and nut tree prunings under meteorological control pending the development of alternative methods of disposal. In applying the control program, temperature inversion criteria and all other factors involving vertical mixing, horizontal transport and contaminant buildup were weighed by District meteorologists in arriving at a daily burn, no-burn decision. As an evaluation of program effectiveness. three years of forecasts for the December?April agricultural burning season have been verified in terms of various indices of air quality. BAAPCD's quantitative Combined Pollutant Index was found to be a reasonable basis for forecast verification. A critical CPI value of 30 appeared as the 80th percentile in the burn frequency distribution and as the 20th percentile in the no-burn distribution An objective technique was developed incorporating minimum temperature at San Jose, near the principal burning sites, with 3000-ft winds from the rawinsonde at Oakland. A test of this method on independent data during the 1970?1971 burning season established its usefulness as a burning forecast tool.