With the growing awareness about global warming has come an increasing pressure on the travel industry, in particular aviation, to take steps towards the off setting of carbon emissions. According to figures from the Stern Review the contribution of aircraft to global warming is 3% today and could rise to 5% by 2050. And although aircraft emissions are the fastest growing source of greenhouse gases, cracking down on flights isn't going to save the world. In comparison road transport accounts for 10%, electricity generation 24% and deforestation 18% (half of this last figure is due to deforestation in just two countries alone, Brazil and Indonesia).



People, however, ignore these facts. Many feel that holiday travel is a luxury and therefore discretionary. In effect, if we are serious about saving the planet then it is something which we can cut without too many far reaching consequences. Rather than people campaigning for cleaner nuclear energy or the preservation of forests they prefer the moralistic feeling of raging against the jet setters and western consumerism.

This is where the moral pressure to plant trees, buy carbon credits and offset our carbon footprint comes from. But the very idea that we can plant our way out of climate change is faintly ridiculous. There's recent research to suggest that planting trees in Northern climes may actually trap heat leading to an increase in global warming. Trees suck up CO2 but in temperate latitudes absorb a lot of heat without losing much moisture; and when the trees burn or decompose the carbon is released back into the atmosphere. And, it would take a forest the size of Dorset to be planted each year, ad infinitum, to offset the UK's carbon emissions - any benefits of which would take years to materialise.

Other offset schemes, such as buying energy efficient light bulbs and stoves for the developing world, may be better. However, there is an underlying problem with the concept of carbon offsets. Rather than seeking ever more ingenious ways to offset pollution we should be trying to produce less pollution in the first place and only then turn to carbon offset schemes.