This month, as Hurricane Ivan devastated the Caribbean and Tony Blair and Michael Howard made speeches about climate change, it became clear that the environment was back on the political agenda. Not before time, because, to date, the world has produced a feeble collective response to the evidence of an increasingly unstable climate.
The Kyoto treaty was a step in the right direction, but momentum has stalled and new leadership is required, of the kind Britain provided in the 1980s, when Margaret Thatcher was the first senior politician to take climate change seriously. As Tony Blair prepares to chair the G8 and EU summits next year, the question is: can he pick up the Thatcher mantle?
The evidence suggests not. Despite his unique relationship with President Bush, he exercises no influence over the United States, whose rejection of Kyoto is an obstacle to international progress. In Britain, Blair's influence is limited by his familiar inability to back fine words with effective action. Having set ambitious targets for Britain to cut CO2 emissions - targets that the Conservative Party supports - the government has not introduced the policies needed to achieve these goals.
Labour's response to the transport sector exposes its failure. This sector represents roughly a quarter of UK emissions; transport emissions overall rose by almost half between 1990 and 2002. Labour's attempt at a green transport strategy consists of higher motoring taxes, no new roads, and more subsidies for trains and buses. Fiscal support for alternative fuels and cleaner cars has been so limited that the greenest fuels and cars still have less than 0.2 per cent of their respective markets.
Meanwhile Labour has ducked the challenge of aviation, whose emissions have risen 85 per cent since 1990 and are likely to double again by 2020. As a result, only one person in eight is aware of the link between aviation and climate change. As for embracing new technologies such as fuel cells that will deliver a low-carbon future, Britain's efforts are pitiful compared with those of the US, Japan, Germany and Canada.
The next Conservative government, by contrast, will adopt a bolder green transport agenda based on four principles. First, consumers must remain free to make transport choices based on an understanding of their environmental impact; second, polluters should pay and be seen to pay; third, market solutions are better than regulation; fourth, Britain's competitive position must not be damaged.
Since four-fifths of travel takes place by car and two-thirds of freight is moved by road, making vehicles greener is a priority. The voluntary targets to cut average CO2 emissions on new cars to 140g/km by 2008 should be extended beyond that year, with higher minimum standards. Agreement is also needed on emissions standards for the heavy and large goods vehicles that contribute one-third of road emissions.
Official targets must be backed by fiscal incentives to create stronger markets for greener vehicles. The government's tinkering with vehicle excise duty to link rates of duty to emission levels is too timid to influence consumer choice. We would like all vehicles classified into bands, ranging from the cleanest to the most polluting. Colour-coding vehicle licence discs according to their environmental classification would help to engage the public.
Wider differentials in duty rates would send a stronger signal to manufacturers and consumers. Road pricing schemes should also reward motorists who use cleaner cars or join car-sharing schemes. Fuels should be categorised by "well to wheel" CO2 emissions, taking account of emissions created in production and distribution. This would open the door to biofuels that can halve emissions.
But road transport is only one part of the picture. Aviation emissions are growing even faster - not surprisingly, as the industry is in effect subsidised by VAT exemption or zero rating on fuel, new aircraft and tickets. This tax-free treatment contradicts the principle that polluters pay. A tax on aviation fuel is the obvious answer, but it would require international agreement, which is unlikely to be reached.
Instead, aviation should be included within the European Union emissions trading systems which would cap emissions. This would benefit environmentally responsible aircraft-makers and airlines. The government could halt runway expansion in Britain until aviation is brought within the emissions trading system.
Air travellers should be made aware of the environmental consequences of their choices by disclosure of emissions levels on air-travel documents. On domestic flights, emissions per passenger are far higher than for the equivalent journey by rail or car. Abolishing air passenger duty on these flights and replacing it with an emissions charge, related to the pollution caused by each flight, would send a clear signal to airlines and passengers.
As a former environment minister and now the shadow cabinet minister responsible for environment and transport, I believe that greener behaviour need not hold back economic growth. Even climate-change sceptics might welcome the commercial advantages of leading the world in green technology.
The longer we delay taking the necessary action, however, the harder it will be to achieve this happy outcome. That Tony Blair has turned his attention to this issue only since he lost the trust of the British people limits his influence.
The issue is a long-term one: a bipartisan approach would be helpful. Thus, I invite the Prime Minister to join our consultation process and debate how best to develop an action plan.
It is not too late for Britain to recapture the leadership on this issue.