Policy brilliance: Jet fuel untaxed: "But how can [air] fares be so much cheaper by plane than rail? One reason is the fact train companies pay duty on the fuel used - although the low-grade diesel that powers locomotives has lower taxes than fuels used by motorists.

"Airline fuel, however, is untaxed - thanks to a series of treaties between countries. For airlines which have to buy 200,000 litres to fill a jumbo jet, this is quite a saving and in turn helps keep fares low."

"British Airways has launched a scheme that allows customers to off-set damaging carbon-dioxide emissions by paying a voluntary sum which is then invested in sustainable energy projects."

An observor could be forgiven for suspecting policy is determined by the interests of influential corporations and industries. A carbon tax by tonne, with no exemptions, would tackle the problem head on.

Policy brilliance: Jet fuel untaxed: "But how can [air] fares be so much cheaper by plane than rail? One reason is the fact train companies pay duty on the fuel used - although the low-grade diesel that powers locomotives has lower taxes than fuels used by motorists.

"Airline fuel, however, is untaxed - thanks to a series of treaties between countries. For airlines which have to buy 200,000 litres to fill a jumbo jet, this is quite a saving and in turn helps keep fares low."

"British Airways has launched a scheme that allows customers to off-set damaging carbon-dioxide emissions by paying a voluntary sum which is then invested in sustainable energy projects."

An observor could be forgiven for suspecting policy is determined by the interests of influential corporations and industries. A carbon tax by tonne, with no exemptions, would tackle the problem head on.