Regional-scale boundary layer ozone variations in the eastern United States and their association with meteorological variations

Abstract

Four regions (north, northeast, south, and southeast regions) were established in the eastern United States to study the variation of the diurnal maximum ozone concentration (DMOC) at the surface with the variation of certain surface meteorological parameters over two 31 day periods, 15 June to 15 July 1990 and 1–31 July 1988. The DMOC variations in the south region were different from those in the north, northeast, and southeast regions. In the north, northeast, and southeast regions, ozone increases and decreases occurred almost simultaneously, whereas in the south region, ozone variations were often out of phase with the other regions. The north, northeast, and southeast regions were directly affected by the same migratory high-pressure systems, if not simultaneously at least consecutively; but these high-pressure systems seldom moved directly into the south region. The south region was affected either by the peripheral regions of these high-pressure systems or by the weak and not well-organized migratory systems that had very little influence in the north, northeast, and southeast regions.