The interconnections between convective boundary layer growth, transport, and ozone during PROPHET 2000.

Abstract

Wind profiler measurements of the CBL during the six-week measurement period conducted at UMBS as a part of the PROPHET research cooperative, were made to better understand the dynamics of the CBL and how transport influences the entrainment of anthropogenic emissions in a remote location. This study also utilizes a simple box model that, when initialized with chemical and meteorological measurements made at PROPHET, predicts the photochemical growth of ozone. Comparisons were made between measured ozone and photochemical ozone fluctuations of pre-entrainment surface-level air, along with CBL height, between 6-20 EDT. This type of comparative analysis was done for twelve case study days for northerly and southerly transport, and allowed for better differentiation as to the causes of ozone variation. Under southerly transport, there is a strong suggestion that ozone increases are largely due to the entrainment of transported pollutants by the growing CBL. In addition, findings did not support the hypothesis that low CBL height necessarily implies higher ozone values as suggested by Dye et al. (1998). Under northerly transport, it appears that the entrainment of clean air by the CBL does not affect ozone levels as much as photochemistry.