Following the Smoke Trail

Public land administrators and air quality managers need better information on the potential contribution of wildland fires vs. anthropogenic sources on possible exceedances of air quality standards. To obtain more precise information in California, a composite network was established for monitoring ozone (O3), nitrogen dioxide (NO2), ammonia (NH3), gaseous nitric acid (HNO3) and particulate matter (PM). The network was located in the Sierra Nevada region of central California. The network provided data for estimates of distribution of air pollutants from urban and agricultural activities, and measured contributions of area wildland fi res on ground levels of pollutants. Information was also gathered during the southern California wildland fires of October 2007, in periods of closure of major transportation routes and Santa Ana winds. Research indicated increased O3 levels during periods of fire activity, but overall effects on diurnal O3 levels appear to be minor compared with the amount of variability attributed to other sources. Particulate matter levels appeared to be the pollutant most influenced by wildland fires