The great myth that lies at the heart of our approach towards the environment

The Prime Minister has been making the right noises on the need to do something about global warming for some time now. In a speech today, he is expected to make more of it, announcing that he plans to put climate change - together with the plight of Africa - at the top of the international political agenda for 2005, during which Britain will, influentially, take the chair of both the EU and the G8 group of rich nations.

The Prime Minister has been making the right noises on the need to do something about global warming for some time now. In a speech today, he is expected to make more of it, announcing that he plans to put climate change - together with the plight of Africa - at the top of the international political agenda for 2005, during which Britain will, influentially, take the chair of both the EU and the G8 group of rich nations.

Making the right noises on the environment is not something to be sniffed at. Today the majority of scientific opinion on the danger of global warming is not matched by any political consensus on action. That is most particularly true in Washington where, we are constantly being told (though we see little evidence), Mr Blair is a figure of considerable influence.

Having said that, the Prime Minister's record of action in matters green is a mixed one. Global warming, undoubtedly the greatest environmental challenge of our time, is driven by two engines in domestic politics - the strategies on energy and transport which between them are responsible for the vast bulk of the nation's production of the main greenhouse gas, carbon dioxide.

On energy, to Mr Blair's credit, his government has presided over an important paradigm shift. In the past, policy was governed by two key considerations. Is the nation's supply secure? And is the price of gas too high in the eyes of voters? Under Mr Blair, those factors have been subjected to a third: how do we secure a low-carbon future to protect the environment?

Yet if the right questions are being asked, the answers currently being given, on how to achieve the pledge to produce 20 per cent of our electricity from renewable sources by 2020, are unimpressive. At present, wind energy is the only solution being taken seriously, and this cannot produce the volume required, most particularly now that proposals for wind farms - which are invariably in upland sites, many of them areas of outstanding natural beauty - are drawing significant opposition from local people and conservationists.

But it is in the second major area that the Government is to be found wanting. A transport policy that continually approves new roads and runways, in the teeth of the resolve on energy, appears to be a case of the right hand not knowing what the left is doing. This lack of joined-up thinking typifies so much of the world's eco-strategy. In Britain, the Countryside and Rights of Way Act considerably strengthened countryside conservation, even as government approval for GM crop trials threatened to undermine it. Energy efficiency incentives for industry are to be applauded, but Mr Blair earns few brownie points on waste - where improvements are driven by EU directive rather than government initiative. Nor can he claim much credit for the fact that our rivers are now cleaner than they have ever been since the industrial revolution; that success is down to the water regulation regime established when water was privatised in the Tory era.

In any case, all that seems small beer set against the apocalyptic business of climate change. The last two UK governments have had a free ride on our Kyoto commitment to reduce emissions from greenhouse gases by 12.5 per cent by 2010; the UK is on course to meet them only because our coal industry collapsed and was replaced by gas two decades ago. But the Government's more ambitious domestic target - to cut emissions by 20 per cent from 1990 levels - is unlikely to be fulfilled.

The great myth at the heart of existing policy is that there can be a win-win solution to the problem. The unpalatable truth is that change of the magnitude needed will only be achieved at a cost. Whether that will be an end to cheap air travel or the desecration of beauty spots by massive wind turbines, or some other solution, is a long way off being decided. The evidence is that Mr Blair's government, along with the rest of our society, has not yet got to grips with what will be the political price of change - and who will pay.