5. Summary
Model simulations of trace gas observations and
dynamics during tropical convective episodes have
shown that ozone formation can be enhanced when
deep convection injects boundary layer pollutants
into the free troposphere. Lightning is an additional
promoter of tropospheric ozone formation through
the production of NOx within convective clouds. A
dedicated cloud outflow flight during TRACE-A
put the rate of tropospheric ozone formation at three
to four times its value in the absence of convection.
The TRACE-A ozonesonde network showed
that the impact of upper tropospheric ozone due to
convective injection from South American pollution
and/or lightning accounted for 20%–30% of
the seasonal tropospheric ozone maximum in the
south Atlantic basin.
A version of the Goddard Cumulus Ensemble is
now coupled with the Goddard Tropospheric
Chemistry model (Fig. 12). The coupled model will
be available for interpretation of aircraft trace gas
data to be taken on future convective sampling missions.
Despite the confirmation of postconvective
ozone formation in TRACE-A, those observations