All great causes involve a tension between collective belief and individual action. A shared agreement that something must be done is not enough to win the battle if people do nothing. This is especially true of the fight against climate change, which must involve all of humanity over many decades, working together to achieve something that none can see or touch and that can only be measured by scientists: an end to the rapid increase of climate change gases in the atmosphere. Faced with this, even the most generous-spirited of people could be forgiven for feeling daunted – surrendering, perhaps, to the hope that someone else will solve the problem.

Urged to do their bit, individuals may wait instead for governments to act, or engineers to come up with technical fixes, or just give in to the comforting but scientifically-unsupported gamble that calamity may be avoided if things go on as they are. Today, the Guardian lends its support to a new movement that aims to defy such fatalism. The 10:10 campaign does not claim that climate change can be wished away through a series of small personal measures taken in Britain alone; it fully supports the need for a deal at the Copenhagen summit in December and for great economies such as the US and China to change too. But if the international agreement is to mean anything, the way people live in this country must change. The 10:10 campaign – named after its target of helping people reduce their individual carbon emissions by 10% in 2010 – will put pressure on government to meet its promises, but it will also have an immediate effect. Climate change gases, once in the atmosphere, stay there. The faster emissions fall now, the less will have to be done later.

All calls for individual environmental responsibility tread a tricky path. On the one hand there is a large and committed green movement, represented this week by the climate camp now in place where the Peasants' Revolt once gathered in Blackheath in south-east London. Many of its supporters, for the best of reasons, want human life to change radically and immediately: an end to the global free market, to meat-eating, to air travel, to all coal-produced electricity. They disapprove of mechanisms to bring down carbon emissions such as the European Union's carbon trading scheme; some dislike technological solutions such as carbon capture and storage. The trouble with these ambitions is that they are never likely to be supported by the majority of the population, who, if told that such things are essential to stop climate change, may simply give up trying altogether. But at the other extreme lies an even more unrealistic response: to pretend that all that individuals need to do is make tiny adjustments to their lives – change a light bulb and save the world – while government sorts out the rest at very little cost. The fight is going to be much harder than that. And even if it eventually repays its costs, as Lord Stern has argued, the bills will arrive first and the savings later.

The new campaign hopes to avoid both pitfalls. As writers explain in the Guardian today and through the next year, individuals have a moral obligation to act which can be met without abandoning the good things about life as it is lived today. Houses can still be heated, but must be insulated too. All sorts of food can still be eaten, but perhaps less meat and less often, and where possible that food should have travelled less far. Walk more, drive less – such things are so obvious that they can seem petty, and yet if enough people and organisations in Britain do them regularly, the effect can be immense. Britain's emissions have fallen since 1990. They must keep on falling sharply: current emissions of over 10 tonnes per capita must drop to two tonnes by 2050. This new campaign will not be enough to achieve that. But it is more than a start; it is the direction Britain must take, if the world as we know it is to survive.

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