Economics, pollution, jobs and noise ... how the arguments stack up

Juliette Jowit
The Guardian, Friday 16 January 2009

Does the government's economic case for Heathrow add up?
The case for Heathrow rests heavily on the conviction of a few powerful groups - led by the prime minister - that expanding the airport will create thousands of construction jobs, encourage more spending by tourists and business, and generate more than 100,000 indirect jobs as a result of the extra economic activity, especially in London. Against that must be set the "costs" of problems created, from living under the jets' roar to the extra bills for carbon pollution permits.
Yesterday the Department for Transport released figures claiming that even if only a proportion of the new slots are used, as suggested in the short term, the net benefit would be £3.3bn over 70 years - about £47m a year. Earlier it had said that if all the new slots were used the net benefit would total £5.5bn - £78m a year.
Concerns have been raised about the claimed benefits: estimates of job creation cannot be proved; others argue that if aviation is not expanded, would-be fliers and workers would offer their cash and time in other sectors.
Critics question the value put on costs. The New Economics Foundation thinktank argues that the government's modellers used a price of carbon that is less than a seventh of the central projection by their own economists, and using that higher figure would "wipe out any economic benefits". Also how much people are willing to pay for things like a good night's sleep is hard to calculate.
Given the relatively small annual benefit even using the government's own figures - £47m is what UK consumers spend every year on fresh herbs, and £78m is one week of John Lewis's sales - serious challenges to the figures could quickly overturn the central economic case.
What does the third runway mean for climate change?
Taking into account all the sweeteners wrapped up into yesterday's announcement, the government has promised that carbon dioxide emissions from aviation in 2050 will be the same as in 2005 - 37.5m tonnes. This would be 30% of the country's total CO2 budget that year, assuming the government's promised 80% cut in total emissions is met by other industries.
It is technically possible, therefore, to expand Heathrow and meet this world-leading target. But there will be questions over whether such a target can and will be met, while the government's Sustainable Development Commission says the amount taken up by aviation would severely restrict future generations' ability to decide what they want to do about emissions from homes, food production and other forms of travel.
Harder to quantify is how other industries, UK voters and overseas countries will react to calls on them to cut their own emissions as Britain expands its aviation infrastructure. Some argue they will accept the UK's hypocrisy as "realpolitik"; others, such as the World Development Movement charity, claim the decision is a "global embarrassment".
What about other pollution problems?
It would be a fair bet that most opponents of the third runway are as worried, if not more so, about local problems, particularly noise and air pollution linked to a range of health issues from breathing difficulties to cancer. The announcement promised that expansion would only go ahead if existing UK noise and EU local pollution limits were met. However, few local opponents will be reassured.
They have long argued that the system for calculating noise "contours" underplays the true extent of the problem (a complaint hard to dismiss by anybody who has spent time under existing flight paths) and they are understandably concerned that a promise that the new takeoff and landing slots will only be used by the quietest planes will not stop noisier aircraft using the old runways. The government also promised new rail links and more funds for low-polluting cars, which are already being relied on heavily to offset the impact of more flights. Both policies will be widely welcomed, but little detail is available.
Fundamentally the case for the third runway rests on promises by ministers: that noise will not be worse and that local pollution will improve. But as the UK has applied for a derogation because it is already over the EU nitrogen dioxide limit, opponents are understandably not confident that the government would not break this or other pledges again in future, and it's hard to imagine a future government brave enough to stop aircraft using the multibillion-pound runway if they broke the rules.
Can the carbon emission of air travel be dramatically reduced as the government claims?
Delivering on many of the promises that make the third runway acceptable depends on making flying less polluting. At the more bullish end, the industry believes that the impact of all the extra flights can be offset by reductions in the pollution emitted per journey. This reduction would be delivered by a mixture of operational changes, from more direct flight paths to design improvements, including sleeker planes, more efficient engines and even low-carbon fuels.
The optimism was fanned by the successful trial of two different commercial jets each using 50% biofuel in one of their engines over the new year. However, sceptics believe many of the claims are exaggerated, or at least will take much longer to implement.
Who is right will depend partly on technology, and partly on incentives: if airlines have to pay enough for the pollution, they will be willing to spend what it takes to develop and then implement new technologies. The current relatively low prices for carbon suggest many improvements will not happen through the market alone. If that's the case, success will rest on whether the government is willing to invest or get tough with the airlines.
Ian Poll, aerospace engineering professor at Cranfield University, said the Heathrow restrictions could provide the impetus for aircraft manufacturers to make their planes cleaner. "Heathrow is such a popular destination operators want to use it. It has stringent regulations ... and [the operators] will demand aircraft that meet the restrictions."
What are the hurdles to the third runway being built?
It is hard to think of an outburst of collective anger as wide-ranging as the response to yesterday's announcement. Perhaps most significant, though, is the Conservative pledge to scrap the runway, something they could do if they win the next election, due by 2010.
In the meantime the wider opposition movement is vowing to do everything it can to fight the plan. Protests, court challenges and planning delays will all be launched.
Yesterday the No Third Runway Action Group insisted: "This is not the end. It is simply the end of the beginning."
Given the outpouring of united, well-funded and articulate anger, it would be a brave person who would bet on the third runway just yet.