The pace of global warming is so slow that it is hard for most mere mortals to grasp its implications. That may explain why so many people refuse to accept the science of climate change. It often requires creative artists to convey the scale of its challenge to humanity. In Earthquakes in London, the highly acclaimed play by Mike Bartlett at the National Theatre, an expectant mother is driven half-mad by her fears for the planet on which her baby will be born.
And for politicians, this gradual pace is one of the greatest problems in forming a policy response to the challenge. In this country, the Ecology Party, precursor of the Green Party that is now represented in the House of Commons, and which holds its annual conference this weekend, was founded only in 1972. Climate change was taken seriously at prime ministerial level only by Margaret Thatcher in 1988. The first partial and non-binding international agreement on the subject was at Rio de Janeiro in 1992. From there it was a long and difficult road, via Kyoto, to the failed summit at Copenhagen last year, and yet the glacial progress of political negotiation inches onward. In November, it arrives in Cancun, Mexico, but China is unlikely to allow much further progress towards binding targets for cuts in warming emissions.
Meanwhile, it can be difficult to detect changes in the glacier's course. And it may seem to be reading too much into a statement by one of the less well-known members of the Cabinet, but Caroline Spelman, Secretary of State for the Environment, could be heralding a shift in emphasis in this country's response to climate change. As we report today, Ms Spelman focuses on how we as a nation should adapt to warming rather than on how we can prevent it.
Where ministers of the previous government promised to make action to "combat" climate change their "top priority", she promises to put "adaptation to climate change at the heart of our agenda". This means rethinking existing infrastructure and future planning to cope with hotter summers and wetter winters. She draws attention to the "best case" forecast of the independent Climate Change Committee, which is for average summer temperatures to rise by one to two degrees Celsius and for a 10 per cent increase in winter rainfall by the 2080s.
In part, this emphasis is a function of the division of ministerial responsibility. Chris Huhne, the Liberal Democrat Secretary of State for Energy and Climate Change, is in charge of the international talks leading to the Cancun summit. He is currently engaged in discussions with other member states about whether the European Union ought to offer a unilateral cut of 30 per cent rather than 20 per cent in its emissions by 2020.
However, Ms Spelman's initiative is an important second strand of coalition policy. The scientific consensus for some time has been that sufficient global warming is already feeding through the climate system that adaptation will be required, as well as attempted prevention. Under the last government, this aspect of policy was played down in order to focus more intensively on the global effort to restrain the rise in output of warming gases. Since Copenhagen, it makes sense to worry more about the consequences of that summit's failure.
One thing that is notable by its omission from Ms Spelman's thinking, however, is a credible mechanism for mobilising resources. Caroline Lucas, the Green Party leader and sole MP, last week compared the Government's response to a call for volunteers for the Home Guard. "Dad's Army will not be enough to prevent climate change or deal with the consequences," she said. She is right. Adapting to climate change will require more than the mere tweaking of planning guidelines and polite requests to local councils. In the long term it will need green taxes on property in vulnerable areas to pay for upgrading flood defences, for example.
Yet the shift towards a twin-track strategy is the right one. This is not simply a matter of "preparing to meet thy doom" but also of national self interest. Just as there are economic opportunities in setting an example to the rest of the world by developing and adopting low-energy technologies, so there are opportunities in developing expertise in adapting to climate change. But Ms Spelman and Mr Huhne must go further, faster and with more hard-headed economic realism if they are to live up to David Cameron's promise after the election to lead "the greenest government ever".