Ozonesonde and satellite measurements of Summer 2010 lightning-induced nitrogen oxides and subsequent ozone generation over the Tropical Atlantic Ocean

A maximum in tropospheric ozone exists over the Tropical Atlantic Ocean throughout the year and is induced partially by long-range transport of ozone precursors. Studies from June 2006 based on the meteorological/chemical coupled WRF-Chem model show that the transport of long-range ozone precursors from the biomass burning region of Central Africa led to a 28-33 ppbv increase in mean tropospheric ozone in the lower troposphere downwind over the adjacent Atlantic Ocean waters and 6-12 ppbv in the middle and upper troposphere further downwind over the eastern Equatorial Atlantic Ocean. Moreover, lightning-induced nitrogen oxide emissions were shown to increase ozone by an additional 6-10 ppbv throughout the troposphere downwind over the same region. Beyond June, lightning flash counts increase within convection associated with the West African Monsoon and increasingly intense westward propagating mesoscale convective systems in the African Sahel, but the quantity of lightning-induced nitrogen oxides and subsequent ozone generation for the summer season downwind over the Tropical Atlantic Ocean is uncertain. To pursue this question the current study will extend the earlier works by utilizing extensive in situ ozonesonde Summer 2010 measurements from Sao Vicente, Cape Verde, Dakar, Senegal, the Southern Hemisphere Additional Ozonesonde Network at Ascension Island, and the 2010 ship-based NOAA Aerosols and Ocean Science Expedition. The ozonesonde data is supplemented with profile environmental data records from the NOAA-unique Infrared Atmospheric Sounding Interferometer products over the Atlantic Ocean and Africa during the same period. This study will also examine cloud-to-ground and in-cloud lightning flash location data from Worldwide Lightning Location Network and the Tropical Rainfall Measurement Mission Lightning Imaging Sensor during this period.