Those backing Heathrow's proposed new runway want to depoliticise the issue entirely. But hard choices are inevitable.
The development of alternative airline fuels needs serious support from national governments if we are going to see greener skies overhead any time soon.
The airline industry's promised technological solutions have not arrived, and they never will.
Major emitters of fossil fuels in South Africa are opposed to a carbon tax.
The general response to carbon tax is not a positive one, but it may be something South Africa will need to accept.
Power of the pen: Obama signs executive order to reduce greenhouse gases from government.
The EPA said it will regulate emissions from airplanes – the latest in a string of environmental and climate regulations Obama has used to bypass the Republican-led Congress.