SURFACE OZONE LEVELS AT TABLE MOUNTAIN DURING STOIC 1989

As a part of the routine operations of the Jet Propulsion Laboratory a tmospheric measurements program at the Table Mountain Facility, the su rface ozone concentration is continuously monitored using a Dasibi pho tometer. The influence of the Los Angeles basin to the southwest of th e facility and the height of the inversion layer cause large fluctuati ons in the ozone concentration, Peaks as high as 200 parts per billion by volume (ppbv) were observed during the Stratospheric Ozone Interco mparison Campaign (STOIC) compared to a normal background level near 5 0 ppbv. These measurements, made during STOIC, were important in asses sing the impact of the surface ozone concentration on the various inst ruments participating in the campaign.