Light Pollution and Astronomy

Mr. Robert Key (Salisbury) (Con): It is a great pleasure to follow the Chairman of the Select Committee. This is one of the more remarkable reports that we or any other Select Committee has produced because it touched a raw nerve, and a lot of people throughout the country find this matter very attractive. I sent the report to my planning authorities—Salisbury district council and Wiltshire county council—and they read it with interest. I think that they will seek to live up to the request that we make of planning authorities.

The great message of our report is that the attitude of each one of us to light can make a difference. Whether we switch off the light or turn down the reflectors so that they do not shine in people's eyes makes a real difference.

I want briefly to concentrate on paragraphs 43 and 44 of our report, which address sky glow. Since we published our report, I have discovered even more disturbing evidence on that. Last August, I was lying in a swimming pool in south-west France, contemplating great things and making waves, when I looked up at an otherwise perfect sky and saw to my disgust that it was blemished by 40 vapour trails; I counted them. Last month on a perfect January afternoon, I was walking past Horseguards when I looked up and—sure enough—counted over 40 vapour trails. Last Monday morning, I looked out of my bedroom window in Salisbury; an otherwise perfect dawn was blemished by over 20 vapour trails.

I then thought, "Well, hang on," because sky glow is a factor in astronomy. It is one of the reasons why very distinguished people say that students should use radio telescopes in Australia and elsewhere rather than look up at the sky from our country. A contributory factor is the clarity of the atmosphere. Particles in the atmosphere can cause disturbance, particularly if optical telescopes are being used. That is a problem at night as well as during the day. Where light is reflected from the ground upwards into the atmosphere, telescopes cannot even be used at night.

I was astonished and rather alarmed to discover how serious the problem of vapour trails is becoming. An increase in air travel will have a dramatic effect on that, and will continue to make life worse for astronomers. Emissions from aircraft contribute far more to the atmosphere than the same level of emissions from surface-based sources. That is known as radiative forcing. It is caused because aircraft emit not only carbon dioxide, but water vapour and nitrogen oxides, both of which can lead to global warming when they are emitted in the stratosphere at the altitude at which passenger aircraft fly.

On the basis of scientific evidence, the intergovernmental panel on climate change reported in 1999 that aviation emissions might have 2.7 times the effect of global warming when compared with a similar weight of carbon dioxide emitted on the ground. That is just a best estimate.

At the beginning of this month—in a document sexily entitled, "TRADEOFF (Aircraft emissions: Contributions of various climate compounds to changes in composition and radiative forcing—tradeoff to reduce atmospheric impact)"—the European Union reported that the potential cirrus cloud impact directly related to aviation emissions in the atmosphere raised the radiative forcing multiplier significantly to a best estimate of 4.4 in 2000 and 4.7 in 2050. That compares with the Treasury figure of 2.5. The contribution of aviation is massive whether we are talking about climate change and global warming or the quality of the atmosphere above the earth. We should consider the problem seriously because it will continue to get worse if we do nothing about it.

What can we do about the problem? I shall finish with the conclusions that many hon. Members on both sides of the House will have reached. We should consider carefully the tax on aviation fuel. There is no doubt that we should develop an aviation policy that accords with national air pollution sustainability and climate change targets and pays for external costs. Early-day motion 1688, which was tabled on 15 September 2003, appealed to the Government to work

" at a national, European and international level to reduce and eliminate the tax concessions received by the aviation industry in the form of tax-free fuel and VAT-exempt products".

It was signed by 120 Members, including me. We should consider such proposals, unpopular though they may be in the short term.

Sky glow remains a problem, even for people who use a pair of binoculars just to look at the moon or stars at night. It is caused not only by pollution from industrial centres. In even the dark-skies regions of our country and planet, if the atmosphere is polluted by aircraft vapour trails, sky glow is an impediment to our proper viewing of the heavens.