Green Power on the march: Thousands unite to rally against global warming

People power comes to the fight against climate change today as Britain witnesses its biggest march and rally demanding the Government acts against the threat of global warming.

From the rock band Razorlight to members of the Women's Institute, from the singer K T Tunstall to the Bishop of Liverpool, the expected crowd of 20,000 in Trafalgar Square will be as wide a cross-section of society as can be assembled anywhere.

The Stop Climate Chaos event brings together an even broader coalition of groups than that behind last year's Make Poverty History events: 40 organisations, ranging from Greenpeace and Friends of the Earth to Oxfam, from Surfers Against Sewage to the Ramblers' Association.

The unprecedented demonstration comes in the wake of the Stern Review on the economics of climate change, published on Monday, and on the eve of this year's UN climate conference, which is being held in Nairobi, Kenya, over the next two weeks.

Two polls show that public concern over the climate is rising steadily, with more than half of Britons now saying that they would accept green taxes to cut pollution, and 40 per cent saying a party's climate change policies would influence the way they vote.

The Foreign Secretary, Margaret Beckett, spoke out on the climate issue yesterday, telling an audience in Delhi that the Indian subcontinent could face a combination of drought and rising sea levels - devastating crop yields and forcing millions to flee their homes - as a result of soaring global temperatures.

Tony Blair was told by Angela Merkel, the German Chancellor, in talks at Downing Street that tackling climate change will be a priority for the German presidency of the G8 group of industrialised countries in the new year.

Ashok Sinha, director of the Stop Climate Chaos organisation, said: "The event reflects how widespread the concern about climate change is. It is emerging out of the green box. People realise it is not just an environmental question but a moral one."

Those who attend today's event will be asked to sign up to the "I Count" register, committing them to an individual contribution to the climate change cause. Those who cannot attend can register online at www.icount.org.uk. A new 16-step "I Count" guide to reducing carbon emissions, featured this week in The Independent, has been published by Penguin to coincide with the rally.

The event has two main political demands - that the UK Government negotiates an international deal to keep global warming to less than 2C; and that it introduces a climate change Bill to the Queen's Speech which - like The Independent's own proposed climate change bill last week - would deliver annual cuts in UK carbon dioxide emissions.

The closest Britain has come to an environmental protest on such a scale before has been the Campaign against Climate Change protests outside the US embassy in London's Grosvenor Square last year, which attracted 10,000 people.

Today's event, however, draws in a wider band of activist groups, some of which are relatively new to climate protest. The Women's Institute's 215,000 membership identified climate change as a primary concern at their national federation AGM last year.

The Ramblers' Association is concerned about the effects of climate change on the footpaths, fells and coastlines of the UK. "The event is a chance for us to indicate that this is very much a fundamental issue of concern for us," said Patrick Brady, head of countryside protection at the organisation.

As a sign of their commitment to the cause, many of those travelling to today's event will do so in a carbon-free way, including cyclists from Somerset, walkers from the West Midlands, and one group paddling down the Thames by canoe from Oxford.

The protest, which sits firmly in a proud tradition of environmental campaigning tracing its roots through the mass trespass movement of the 1930s to the anti-road building movement of the 1990s, shows Britain is not prepared to sit back and wait for politicians to find answers to the climate change crisis.

New public opinion readings confirm that. A Populus poll yesterday for BBC2's The Daily Politics programme showed that more than half of Britons (53 per cent) agree the Government should impose higher taxes on activities that cause pollution - even if it means the end of cheap flights and driving a car becomes more expensive (45 per cent disagreed).

A survey undertaken by TNS Omnimas for Stop Climate Chaos, reveals only 4 per cent of the population believe Tony Blair has made effective progress on the issue, while 40 per cent claim climate change policies would influence their vote.

Today's events

* 11.15am. Christian church service at Grosvenor Chapel, 24 South Audley Street , W1, addressed by Rt Rev Richard Chartres, Bishop of London.

* Midday. The first of a number of "feeder" events that anyone can join. Around 5,000 people are expected at a Campaign Against Climate Change rally outside Grosvenor Square.

Another, under the banner of the People and Planet organisation, takes place in Malet Street, WC1, followed by a procession to the main event in a Rio-style parade.

* 12.30. The Rt Rev James Jones, Bishop of Liverpool, addresses a gathering in the church of St Martin-in-the-Fields, staged by Tearfund and Christian Aid. By now, street performances will be under way in Trafalgar Square. A big screen will also be in Trafalgar Square screening films about climate change and the work organisations are doing to tackle it.

* 1pm. Main event starts in Trafalgar Square. Speakers and performers include K T Tunstall, Miranda Richardson, the Bishop of Liverpool, Razorlight and Adam Hart Davis. The event wraps up at 3pm.