| In order to better understand the relationship between tropospheric ozone levels and volatile organic compound (VOC) precursors, several field sampling campaigns were conducted in the U.S. Measurements were made at the surface and aloft (at elevations in the atmosphere). Ambient concentrations of volatile organic compounds, nitrogen oxides, ozone and meteorological parameters were of primary interest. VOC determinations included non-methane hydrocarbons (NMHC) as well as carbonyl compounds such as formaldehyde. Isoprene, a biologically emitted hydrocarbon, was of special interest in these studies.{09}Isoprene has been shown to have a significant impact on the photochemical production of ozone in urban and rural environments.; In Western Washington State, multi-year measurements of VOCs, NO x, and ozone provided necessary data for regional photochemical modeling efforts. Particular attention was given to better understanding the regional biogenic VOC emissions and the impact they may have on ozone production in the Pacific Northwest. In NE Oregon, a long-term study of isoprene emissions was conducted in a poplar plantation and the results were used to examine emission behavior on seasonal scales. |
