The general scope of this project is to examine the contribution of biogenic emissions to ozone levels in several urban areas and to assess the attainability of meeting the new 8-hour ozone standard. The specific project objectives are to:

1) determine the sensitivity of biogenic emissions to changes in biogenic model inputs,

2) determine the likely range of ozone levels attributable to biogenic emissions, and

3) assess the adequacy of current biogenic models and recommend areas needing improvement.