Satellite observations of tropospheric column ozone (TCO) imply an elevation of ozone during the period of June, July and August. The source of this ozone could be from the long-range transport of tropospheric ozone from Central Africa, the natural production of ozone via lightning and subsequent NOX production, stratospheric intrusions or incorrect satellite estimates. During the early summer of 2006 (June-July), in concert with the African Monsoon Multidisciplinary Analysis (AMMA) Special Observing period 1-2, tropospheric ozone measurements were launched aboard the Ronald H. Brown in equatorial latitudes of the Tropical Atlantic along the N-S transect of 23 W. Here we present the results for the period of June 11-15 during the first leg of the cruise and June 26-29 the second leg of the cruise. Our results show (1) elevated mid and upper tropospheric ozone concentrations, (2) higher concentrations of ozone during late June relative to early June. The source of the higher ozone concentrations were in part due to the transport of ozone and ozone precursors from Central Africa during leg two, whereas during leg 1 the low level flow from Central Africa was not directed toward 23W. The elevation of ozone in the mid/upper troposphere was likely due to lightning or the horizontal transport of ozone precursors from biomass burning in Central Africa that ingested into deep tropical convection to the north.