First ozone sounding results over the UAE

The first ever campaign of observing vertical profiles of ozone over the UAE began on January 24, 2006, with a couple of balloon flights carrying ECC ozonesondes to understand the characteristics of the chemical and dynamical structures at this unique tropical location (latitude 24.45N; longitude 54.22E). The campaign was continued sporadically over the past several years. A total of six ozone profiles are available to date. Preliminary results of January profiles indicate that the stratospheric ozone is quite stable while thick polluted layers confined to the lower tropospheric heights show enhancements in ozone contents. Excessive values of ozone concentration in the range 45–50 ppbv at the ground levels are observed. These values are much larger than those observed at other subtropical sounding stations using the same technique. The difference in values probably reflects either the elevated levels of air pollution due to petrochemicals and automobile emissions in the UAE or the effects of photochemical production and destruction of ozone by horizontal transport and convective uplift from the surface. These processes are affected by higher levels of solar radiation and large variations in the relative humidity in the tropical/subtropical troposphere.