The International Air Cargo Association (TIACA) has disputed the findings of a recent report on aviation’s impact on the environment as “misleading” and based on “considerable uncertainty” of some of the gases usedin the measurement process.

The air cargo carriers argue that the authors of the ‘Aviation and Global Climate Change in the 21st Century’ paper had previously assessed aviation’s contribution to climate change to be three per cent in the Fourth Assessment Reports (AR4), but in their latest report they have increased the figure for aviation’s contribution to climate change to 3.5 per cent without cirrus and 4.9 per cent with cirrus.

TIACA is challenging the increase which it says includes updated values of kerosene fuel sales based on International Energy Agency reported data. This latest report used the data to revise aviation’s radiative forcing (RF) to reflect an increase in traffic, fuel use, and total aviation RF over the period 2000-2005, including estimates of cirrus cloud formation.

The association said it believes a more accurate assessment was reported in 1999 by The Intergovernmental Panel on Climate Change (IPCC) in which it estimated that aircraft emitted two per cent of man-made CO2 – a figure it forecast would grow to three per centin 2050.