The Air Transport White Paper, published three years ago next month, required all airports to submit their masterplans for development up to 2030. As we report today, these estimates are now coming in. And sobering reading they make. To take just a few examples: Luton predicts that its present 7.5 million capacity will have to expand fourfold to accommodate 30 million passengers. Bristol envisages that its passenger numbers will triple to 12 million, while Nottingham, Manchester and Aberdeen all expect present passenger numbers to double.
These figures are little short of terrifying. Emerging into the public domain in a week that opened with publication of Sir Nicholas Stern's report on the cost of combating climate change, they should give serious pause for thought. Even if they are replicated nation-wide at only the most conservative level, we are still looking - at very least - at a doubling of air passengers using UK airports over 25 years. In fact, the early submissions suggest that the projected increase could be far greater.
The most obvious concern is what impact such an increase would have on carbon emissions, and whether a tax on airline fuel or airport use would go any way towards restraining it. But there are other, more local, worries.
To cater for the increase, many airports plan to build additional runways and add acres of car parking. A public inquiry is considering Manchester airport's plans for 1,500 parking spaces inside the Cheshire green belt. Add the new terminal buildings and technical facilities for servicing at least twice as many planes as at present, plus the inevitable noise pollution, and what we have is a picture of proliferating blight.
In the light of the Stern report, there is surely a conclusive argument for sending all these airport plans back to the drawing board. Expansion requirements should be reassessed, to take into account the likely effect of new "green" taxes. Where possible, ecologically friendly public transport connections should be preferred to extra car parking.
Above all, time is needed to allow the individual plans to be examined centrally and considered in the context of national requirements overall. The purpose would be not to preserve the concentration of air transport links in the South-east - more direct regional links may be desirable if they reduce distances travelled by air - but to co-ordinate development and minimise duplication.
From now on, everything the Government does will be seen through the green prism of the Stern report. The last thing Britain needs - whether in 2030 or before - is anything that could be seen as facilitating more air travel.