Co-Occurrence of Ozone and Acidic Cloudwater in High-Elevation Forests

摘要

A chemical climatology for high-elevation forests was estimated from ozone andcloudwater acidity data collected in the eastern United States. Besides frequent ozone-only and pH-only single-pollutant episodes, both simultaneous and sequential co-occurrence of ozone and acidic cloudwater were observed a few times each month above cloud base. Co-occurrence was observed more frequently at two southern sites than at two northern sites. This co-occurrence represents a multiple chemical stress whose biological implications can now for the first time be studied in controlled exposures of trees. (Copyright (c) 1991 American Chemical Society.)