ESTIMATION OF AIR-QUALITY BY 3-DIMENSIONAL AIR SIMULATION-MODEL - (EFFECT OF LOW-EMISSION VEHICLES ON AIR-QUALITY IMPROVEMENT IN THE GREATER LOS-ANGELES AREA)

The effect of the introduction of low-emission vehicles on air quality improvement in the South Coast Air Basin (SCAB) around the Greater Lo s Angeles area in California is studied using a three-dimensional nume rical simulation model which solves the urban-scale atmospheric diffus ion equations and photochemical reactions. The results indicate that r eplacing all the light duty vehicles (LDVs) with ZEV, which satisfy th e strictest regulations, will reduce the total mass emission from auto mobiles (CO by 83%, NOx by 66%, and ROG by 85%). shown. Replacement of LDVs with 1994 regulation level vehicles, TLEV, LEV and ZEV, will red uce the maximum ozone concentration by 14%, 17%, 18% and 20%, respecti vely.