Thank you very much for inviting me here tonight.

I want to use this opportunity to talk about why a greener, better, fairer society has never been more urgent, and what I think needs to be done to get us there.

Our planet is telling us that we need to change the way we live. It is asking us to live with it rather than just on it. Why?

Because we are going through the planet’s resources faster than they can be renewed – in Europe it’s three times faster. With huge population growth, at this rate we’ll need another two planets by 2050. The problem, of course, is that we just have the one.

Because the Millennium Ecosystem Assessment is telling us that 60% of the world’s ecosystems are being degraded or used unsustainably.

Because biodiversity is being wiped out with species becoming extinct at one thousand times the normal rate.

Our planet may be going through its sixth great extinction event, but you wouldn’t know it to read the headlines.

Because the acidity of our oceans has increased by 30% since the Industrial Revolution – a faster pace of change than at any time in the last 55 million years.

Coral reefs are dying. Fish stocks are collapsing. Climate change is causing sea levels to rise. Already islands in the Indian Sunderbands are being claimed by the sea, forcing thousands of people to seek new homes on higher ground.

Because the concentration of carbon dioxide in our atmosphere has increased by 40% since the Industrial Revolution – a concentration higher than it has been for at least the last 650,000 years. Levels of other greenhouse gases, such as methane and nitrous oxide, have also increased significantly.

And the impact of all of this on our lives and our economies could not be clearer.

2008 gave us the starkest warning yet of what can happen when potential threats to the world’s food production and security become real.

Drought, poor harvests and high oil prices pushed up the cost of grain. Some cities saw riots as the cost of a day’s food rose sharply.

And extreme weather is becoming more common and more severe.

Abroad, warmer seas are likely to result in increasingly severe tropical storms.

At home, we know from the Environment Agency that the summer floods of 2007 cost this country £3.2 billion.

We are no longer anticipating a global environmental crisis. We are experiencing it.

And for the sake of our society in twenty years time, let alone fifty, we must take responsibility now for the future of generations to come and for the kind of society we are trying to build.

It’s something we’ve done throughout human history; recognising problems of our own making, fixing them, putting something better in their place.

So why are we finding it hard to do ? I think there are two main reasons why.

The first is about confidence.

After all the horrors of the second world war, there was a tremendous sense of optimism about the future. Onwards, upwards, better. It was a spirit that rebuilt Europe, put men on the moon and invented the computer and the internet.

My generation – those born in the 1950s and 1960s – were the beneficiaries of this. And yet our generation now fears that the future for our children may not be as good as the past was to us.

We are the first to be told that the planet’s resources are running out and that the climate is changing.

We look at the growing epidemic of obesity.

We wonder how we will manage in retirement.

We fear that our children may not be able to afford to buy a home.

And given what we can see around us you can understand why there has been a collective loss of personal, economic and environmental optimism.

So we must reverse this if we are to prosper.

The second reason concerns the facts.

We know that the evidence on climate change is clear – despite some recent problems – but as Copenhagen showed, not everyone can see it or its consequences or wants to. Climate-change deniers and those who want a free hand to plunder our natural capital are frantically trying to obscure the reality.

And we saw their political friends go to work in the run-up to Copenhagen.

The attempts by Peter Lilley and Nigel Lawson to cast doubt on both the evidence and the urgency of the problem was the clearest indication so far that Tory flat-earth thinking on climate change hasn’t been airbrushed away.

But it’s not our job to convince the Tories; its David Cameron’s. And yet we know that Conservative councils block three times as many wind farms as they approve. The recent poll of 141 Tory Party candidates showed that climate change was bottom of their list of priorities. Bottom; below cutting red tape.

And at the very moment when we need Europe to continue to lead on climate change, the Tories are busily isolating themselves in Europe.

Mr Cameron clearly has an uphill struggle. We read that 10 would-be candidates have been sent for green ‘re-education’ by Steve Hilton, but that can’t hide the truth.

John Sauven, the executive director of Greenpeace, puts it this way: “There is a gap opening up between where David Cameron and the top leadership are, compared to where their base is.”

No wonder some people are describing climate change as the ‘new Europe issue’ for the Tories.

Well it seems to me that the Conservative base is on the warpath against action on climate change and the environment. And I think the only thing the Tory green tendency can do now is to circle the sledges and the huskies and wait for the inevitable.

Meanwhile, we have work to do. This party has always stood for social justice and we will not have a genuinely green society until it provides for everyone within it.

We have always been the party of aspiration, unafraid to take the political and practical decisions needed so that the lives of every citizen are improved alongside the environment in which they live.

We have always believed that the state does have a part to play in helping us to do this and that Government has to accept this responsibility, rather than shirk it.

And most important of all, in the last 12 years we have applied these beliefs to what we have done and we should be proud of what we have achieved.

This Government secured the first legally binding carbon reduction targets of any nation and has encouraged other countries to make the same commitment.

The leadership shown by Gordon Brown and Ed Miliband in Copenhagen demonstrates why we have the international credibility to do so.

We’ve created England’s ninth national park, the South Downs, completing the work started by Attlee’s post-war Labour Government.

The Marine and Coastal Access Act – the first of its kind in the world – will protect the wonders beneath our seas and open up our coastline.

The Food Strategy – the first for 60 years – sets out how food production and looking after the environment can and must be combined.

We have more than quadrupled the rate of household recycling in just over a decade, and with the help of the Landfill Tax, reduced the amount of waste being sent to landfill by nearly a third.

Our Environmental Stewardship Schemes pay farmers to restore hedgerows and put in buffer strips to reduce nitrate pollution from the land into our water.

We are leading the world in the production of electricity from offshore wind.

That is the story so far. Now we have to tell the story of what could be.

To make the case that change is neither terrifying nor impossible, but achievable. To see that change as the continuing story of humankind. It teaches us much if we choose to learn from it. Adapting is what our species does.

And to have confidence.

Look at our past. Look at the economic, social and political advances we have made. Look at the answers we have found to the problems we faced, drawing on science, and technological skill and sheer political will.

The Industrial Revolution gave us new technologies, cheap goods and huge growth, but it also produced environmental damage, over-crowding and indifference which allowed wave after wave of epidemic disease to prey upon the poor.

Cholera arrived in Britain in 1831. Successive epidemics – as far afield as Durham and London – killed about 52,000 people.

Doctors claimed it was airborne.

Self-interested municipal governments did nothing.

It took the son of a labourer, John Snow, to prove that cholera was both carried in water and preventable. He did so in 1854 by persuading the authorities to let him remove the handle of a water pump at the centre of an epidemic in Broad Street, Soho.

The result? New cases of cholera fell across London. Snow was right. His evidence became widely accepted.

By 1866 most of London was connected to Bazalgette’s new underground sewers, which did more than anything else to prolong life expectancy in 19th century Britain.

That year saw the very last cholera outbreak in Britain.

From Jenner’s smallpox vaccine to Sanger’s DNA sequencing, science and technology have moved us forward as a society, time and time again. But only when we overcome fear, and complacency and seize imagination.

And that brings me to the last, and biggest, task we face.

Do we believe it is possible?

Some answer that the only way forward is to go back, to give things up, to put the computer on the compost heap and return to where we were.

There is a strand of the green movement that thinks this, and points the finger at people and says: “you have all been very, very bad”.

Others say we are a broken nation.

I think those who say these things are profoundly mistaken.

Not because the scale of the challenge isn’t huge – it is – but because it motivates no-one, it encourages nothing and it does not change anything.

When Martin Luther King confronted the great challenge of his era, he did not start that extraordinary speech to the multitudes who had marched on Washington with the words: ‘I have a nightmare’. He said something else.

And our message, too, has to be one of hope.

It is not about going back; it is about bringing back that sense of optimism about the future. That belief that we can do it, and that what we do as individuals and in our communities does make a difference.

It is about putting the environment at the heart of a radical Labour’s election manifesto.

It is about standing up against the unequal distribution of a good environment at home and across the world.

It is about helping people to see that our future needn’t be uncertain if we make the right choices now, and that we ourselves – wherever we live – have a part to play.

What kind of society do we want Britain to be in 20 years time?

Will we have reversed the rising tide of asthma, obesity and diabetes caused by poor air quality and junk food saturated with salt and sugar?

Will the environment reflect the fact we have learned to value it? Will we have slowed the extinction of species and their habitats, cleaned up our seas and stopped sending waste to landfill?

Will our economy be one of the world leaders in adaptation and green technologies, creating hundreds of thousands of skilled jobs, retro-fitting our houses and workplaces and meeting more of our energy needs through renewables?

Will communities feel they have the means to transform their own lives?

It’s the things we do now that will give us the answers to these questions.

Like making it easier to do the right thing by the environment.

The growing waiting lists for allotments, the decline in the use of plastic bags, the increase in recycling all show that people want to do the right thing – if they are given the means. Or, better still, make the means for themselves.

Making the best use of technology.

Only 20 years ago the internet was less than a decade old, mobile phones were expensive bricks and the idea of a commercially manufactured hybrid was science fiction. Not now.

Today we have triple A rated dishwashers, fridges and washing machines. We’ve got hybrid cars, Kindle and renewable energy.

The technological progress we have made already is amazing. And it’s this technology and science that we must use to the full.

Investing in the jobs of the future.

Britain has always been a nation of innovation. And unlike the flat-earthers who say we can’t afford to tackle climate change, I say that environmental change is actually the big opportunity for our economy.

The market in low carbon and environmental goods in the UK is worth nearly £110 billion and already provides nearly 900,000 jobs.

We lead the world in offshore wind power and our water-management expertise is in increasing demand internationally.

This year saw 25 leading companies, including GE and EDF, announce that working with universities they plan to develop the technology to retro-fit 200,000 homes and deliver near-to-market green technologies.

Developing and selling our home-grown expertise in adaptation should become one of our most valuable exports.

A greener society in 2030 will not look like science fiction. We are already using many of the products we will be using in 2030, eating the same food and driving cars that will look similar.

The difference will be in the way we produce them, the way we buy them and the way we dispose of them. The difference will be technology and the way we apply it.

Houses, for example, that are triple-glazed and wall-insulated as standard, where feed-in tariffs are the norm and the use of renewable energy by communities is rising.

Food that is produced sustainably. Where our farmers get a decent price for their crops, and where people know where their food comes from and have the information they need to make sustainable and healthy choices.

Cars which are low or zero-carbon to run and whose manufacture squeezes every last drop of efficiency from the resources used to produce them.

Energy from renewables, where communities have taken the lead.

Like the remarkable Neilston Development Trust, whose members I met in Scotland last Friday with Jim Murphy. They want to make their 5,000 strong community sustainable. They have a plan. And, thanks to the determination of those running the Trust and a partnership with a renewable energy company, four wind turbines will be built on the hill overlooking Neilston – giving the community an income of £100,000 a year.

I asked them whether there were there local objections to granting planning permission? No, I was told, because the people have a stake in the future that they themselves have designed.

Stories like this – and if it can happen in one community, it can happen in every community – show that we are moving in the right direction, but we need to hurry up. Not by compromising on what’s needed, its urgency or its cost. Not by demanding sacrifices from growing nations that we ourselves have not been prepared to make. And not by believing that it’s a choice between economic growth or a greener society.

That way will mean that the sceptics, the deniers and their friends in the Tory party will have succeeded.

That way lies not a green society but a mean society, where those who can’t afford to buy their way out of climate change will suffer the most.

Our way is different.

And to anyone who cries it is impossible – we can’t do it – all I would say is this.

Stop, look back 200 years, and ask yourself what life was like for most people. And then ask yourself what our forebears and our ancestors would say if they walked through that door this evening, looked around them and saw what we have achieved. They would be astonished by what we have done.

So just as our ancestors transformed their lives, so we now together have to transform ours.

And we will do it not by denying knowledge and experience, but by treasuring it.

Not by ignoring progress and technology, but by embracing them.

Not by using all that we have for a privileged few, but by using it for every single member of our society.

Not by seeing people and communities as the obstacle, but seeing them for what they really are – the answer.

The truth is that we already have the means.

They are in our hands.

All we need to find now is the will.

Thank you.

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