New research warns that increasing demand for air travel could have an impact on ozone levels and climate in the future. The review, `European Scientific Assessment of the Atmospheric Effects of Aricraft Emissions' published in Atmospheric Environment, says that exhaust gases released at aircraft cruising levels of 10-12 km have increased ozone levels in the upper troposphere were it acts as a strong greenhouse gas.
Carbon dioxide is also having an impact although aircraft only account for two to three per cent of total CO2 emissions. The authors warn however that growth in air traffic will increase this contribution, impacting on climate change and also on ozone depletion at higher altitudes up to 20km, where the next generation of aircraft will operate.
New less-polluting engines and more fuel efficient aircraft technologies are needed, they conclude.