ECC ozonesonde ozone and potential temperature profile data for several stations from 25.05 ¿S to 19.6 ¿N were processed to look for the type, seasonal behavior, and vertical distribution of the laminar structure in the troposphere and lower stratosphere. The fractions of ozone laminae associated with Rossby and gravity wave induced laminae were determined from correlations between ozone and potential temperature structure. Gravity-wave-induced laminae in the stratosphere were found to be associated with deep convection in the winter months and winds form the southwest in the summer months for the Hilo station, and orographic wave activity for the Pretoria station in September. No significant Rossby wave activity was found for these stations. Lower tropospheric laminae of mixed characteristics were found to be prevalent at the Hilo, related to transport from the northeast, and the continental tropical stations in the June-August period, which are associated with biomass burning.