THE world is potentially on the cusp of taking powerful united action on climate change. The impact of this action could improve the lives of millions. A document from the Global Commission on the Economy and Climate, The New Climate Economy Report, which is published this week, gives real hope that this action will spur sustainable economic growth. It has been compiled by a group of economic experts, including the CEO of Unilever, Paul Polman; the former President of Mexico, Felipe Calderon; and the British economist Nicholas Stern.

Our politicians need our permission and encouragement, as they approach a year of complex international negotiations. They need to hear the prophetic voice of Christians calling for gospel action, good news for the world, and a vision of the future filled with hope, and inspired by God's will for his people.

Three global summits addressing this issue will take place over the next 14 months, starting with a meeting of world leaders in New York next Tuesday. The global community will then be working towards a crucial agreement to limit greenhouse-gas emissions, first at a UN conference, COP 20, in Lima, in December this year, and then in Paris at COP 21, in December 2015.

The Intergovernmental Panel on Climate Change (IPCC) is made up of more than 2500 scientists from around the world, and 195 countries are members. It delivered its clearest message so far a year ago, stating that it is now 95-per-cent certain that human activity is the key factor driving climate change (Comment, 27 September 2013). Its message is crystal-clear. We can no longer claim ambiguity about the facts.
 

THE report this week by Polman, Calderon, Stern, and others helps to prepare the ground by showing that climate action is an affordable way forward for the global economy. It has been given to all governments through their UN permanent representatives, and directly to heads of government, finance, and climate ministers in about 25 capitals.

The document, which was commissioned by seven countries (including the UK), states: "The evidence presented in this report suggests that the low-carbon growth path can lead to as much prosperity as the high-carbon one, especially when account is taken of its multiple other benefits: from greater energy security to cleaner air and improved health."

All the evidence that we have now supports the view that action on climate change is not only necessary, but also a viable economic option. It is only political will that is holding back the action that is needed. Our politicians have not heard clearly enough from us, the electorate, that we want decisive moves on climate change.
 

THE Bible returns to the thread of justice over and over again but, at present, the poorest in the world, who have done the least to cause climate change, are suffering its most serious consequences. Our children and grandchildren will suffer in a similar way.

Global and generational injustice demands an unequivocal response from Christians to call for our politicians to set this right. We can witness to the gospel ourselves by being a prophetic voice to our political leaders, asking them to commit themselves to take the bold and principled action that is needed.

The Hope for the Future campaign is designed to help Christians to do precisely this. It was started by a group of diocesan environmental officers from Yorkshire and the north-east, but now covers the whole country. Its aim is to encourage as many people as possible to write to their MPs and parliamentary candidates, and preferably to visit them as well, asking them to ensure that their party commits to decisive action on climate change in its manifesto for the 2015 General Election.

The report this week has produced evidence that action on climate change is affordable. It has also proposed a ten-point plan for global action. We have the evidence, the resources, and the steps towards a solution. David Cameron pledged that this Government would be the "greenest ever", and next week he will travel to New York as our representative with the chance to act on his promise.
 

THE Church has a mandate to stand up for the poor and the powerless; to point to injustice and oppose it; to be sacrificial in our actions and attitudes. So Hope for the Future, working in collaboration with Christian Aid, especially in its Hunger for Justice weekend on 18-19 October, is encouraging churches to run "Climate Write-Ins", targeting MPs and parliamentary candidates with personal messages asking for climate action.

Paul Blomfield, MP for Sheffield Central, has said: "I've been encouraged to have lots of letters, many from people in the churches, letting me know that they want bold and realistic policies to tackle climate change from all the political parties. . .

"To get the strong and effective climate policies we all want, keep on campaigning and lobbying, and keep on sending the letters, emails, and tweets."

The Hope for the Future campaign is fundamentally about exercising our right and duty as citizens to use the power that we have to make our voices heard. The campaign gives all of us the opportunity to take a positive, compassionate, and effective step. This is some-thing we can do about climate change. I urge you to take this simple, but vital, prophetic action to ensure that there is indeed hope for the future for our children and grand- children.
 

Dr Steven Croft is the Bishop of Sheffield.
Further information is at hftf.org.uk.