GLANCING SKYWARDS gives the impression of limitless space, a vastness beyond human influence. But most of the greenhouse gases that are causing our world to warm up are trapped in a layer of air less than six miles thick. This thin veneer of atmosphere is where our climate and weather are born, and is where we are now creating rapid and dangerous changes.

It is predicted that serious climatic disruption is imminent, which is expected to lead to a global mass extinction of wildlife species. It will create shortages of fresh water, and will affect food production. This in turn will impact on food security. Rising sea levels will eventually deprive the world of food production capacity. A range of climate-change-related impacts working in concert could lead to social instability, mass migrations of people, the rise of authoritarian regimes, and international conflicts.

Even the Pentagon, has concluded that "with over 400 million people living in drier, subtropical, often over-populated and economically poor regions today, climate change and its follow on effects pose a severe risk to political, economic and social stability." Strong words from an official body in the country that has done more than any other to deny that human-induced climate change even exists.

ALTHOUGH CLIMATIC UPHEAVAL is poised to precipitate a mass extinction, while simultaneously threatening economic collapse and social chaos, it still warrants barely passing recognition in popular and political debate. Tony Blair is unique among world leaders in prioritising negotiations on climate change at key international meetings, but even he is failing to deliver significant progress in reducing pollution in his home country. That global society is finding it so hard to appreciate the scale of threat at hand, let alone do anything about it, is a fact of great historical significance. But what is the problem in getting people to see the importance of what is being said by the scientists, campaigners and politicians, let alone what is obvious from the weather, birds, flowers and frogs?

Perhaps one reason is that many people are so divorced from nature that they have few ecological handles upon which they can anchor their experience. Worse still, perhaps, the one bit of nature that people do notice, namely the weather, is in some places more pleasant because of the first noticeable impacts of climate change. The earlier arrival of spring, and summer temperatures lingering into autumn lead some to believe that climate change is a good thing. Perhaps the fact that the world's most industrialised countries are mainly in seasonal temperate zones is a part of the problem. If the people most responsible for causing climate change also perceive a short-term improvement in their weather this can further delay the action needed.

Another problem relates to the magnitude of what is happening, and the impression that we humans could not possibly be responsible. The climate is so fundamental (and in popular terms so poorly understood) that it seems to many most unlikely that people could realistically have an impact on it in the first place. And because the issue seems to many people so big and so difficult to comprehend, the small actions needed to deal with it are not seen as sufficient or placed in any kind of meaningful context.

One more challenge comes from the tendency for people to see climate change as posing no threat to them, certainly not personally or right now. All of us have only so much capacity to take on the many things we should be worried about, or which we should prioritise for action ourselves. It seems that we are able to concentrate our attention, thoughts and behaviour only on the most immediate threats. Perhaps that is why people responded so much more decisively to what they heard about GM foods. The causes of climate change are also hard to visualise. On top of all that, the substance of greatest concern, namely carbon dioxide, is invisible, occurs in relatively tiny quantities in the atmosphere, occurs naturally and is essential for life on Earth.

There is also still considerable popular confusion. Although it is scientifically demonstrated that climate change is occurring now, is caused by people and represents a major threat, it is still portrayed by many as not happening, as a challenge we must face only far into the future or as a natural aberration that can be safely ignored. The confusion that accompanies these messages has undoubtedly slowed down widespread demand for political action - especially in countries where such obfuscation and doubt have been carefully nurtured by various political and industrial special interests. The USA is of course the most notable and damaging case in this respect.

EVEN WHEN PEOPLE do take on board the implications of rapid global warming, there is a huge barrier to action arising from the small impact that many individuals perceive they personally can make on such a large-scale and long-term issue, especially when others appear unconcerned, or show no sign of behaviour change. The question then becomes "Why should I do anything if everyone else will carry on as before?" The same argument is played out politically when, for example, some prominent figures in the Western countries say that there is no sense in taking action to reduce emissions because any benefit will be cancelled out by the increasing pollution coming from rampant economic growth in China and India. So, what should be done?

It would clearly be folly to put faith in any single technology, or worse still wait for some big disaster that might somehow galvanise action. Disasters are already happening: for example, 25,000 people died from excessive heat in Europe in 2003 and yet there has been no impact on policy resulting from that.

In the end a lot of small actions will have to be taken in order to address this problem. These will come about as a result of growing public awareness that changes cultural values that then help shift politics, policy, law and ultimately how we generate and consume energy and how we judge a good life.

This leads to two broad conclusions. The first is that since public awareness is the key, we must strengthen all our efforts to spread the word about climate change. Everything from making hard-hitting television programmes to talking about the issue to family and friends, and everything else in between. Secondly, and on the basis of rapidly expanding public awareness, it is vital that governments establish the frameworks necessary to harness effective solutions.

Energy-efficient light bulbs and bicycles may seem modest symbols of global survival, but they are real and send powerful signals. While wind turbines are not the whole answer, they are certainly part of it. So are solar power and the new technologies that are emerging to harness the energy in waves and tides. There is also the prospect for huge progress in the form of micro-generation and the development of local electricity distribution grids. Using cars less and making them more efficient, curbing growth in the use of airliners, and developing far higher efficiency standards for a wide range of appliances can all play a central role, too. And by talking about what can be done, as well as the scale of the challenge we face, we can inspire hope.

GIVEN THE URGENCY of the problem, and the evident failure of voluntary efforts to curb emissions, Friends of the Earth is campaigning in the UK for new laws that will require the government to make cuts in greenhouse-gas emissions every year starting now. What the new climate law would say is that real cuts must be delivered every year. How it is done will vary depending on the cost and practicality of the different opportunities available at any one time. One year action could be focused on phasing out old coal-fired power stations; another time the emphasis could be on replacing carbon-based fuels with new renewable energy capacity.

The point is that the requirement to act would always be there, no matter what party is in power, or how fashionable it is at any one time to make speeches about climate change. It would be a predictable and regular requirement that would in the end bring down emissions by the amount needed. It is positive that there is increasing consensus about the need for long-term targets, but these will not be reached unless we begin the process of change immediately. We need our governments to act, and to act now. o

For more information please visit: www.thebigask.com.

Tony Juniper is Director of Friends of the Earth.