Fire and brimstone are coming to the aid of US science, as evangelical scientists and their allies in the religious community embark on a battle against climate change.

“The time has come...for destroying those who destroy the Earth,” says Calvin DeWitt, a professor of environmental studies at the University of Wisconsin, Madison, quoting from the Scriptures. The Bible teaches stewardship of the planet, he says, which is partly why 86 prominent US evangelical Christians last month signed the ‘Evangelical Climate Initiative’ calling for mandatory limits on greenhouse-gas emissions.

The movement began in 2000, when 50 evangelical scientists — including DeWitt — signed a statement calling for policy-makers to take steps towards reducing the threat of climate change. It is a rare move in the United States, where environmentalists and the religious community often find themselves in opposite camps. Climate activists hope the initiative will have the political clout to help sway President George W. Bush's administration towards mandatory emissions cuts. Bush has not signed up to the international Kyoto Protocol on regulating greenhouse gases. Instead, he is promoting clean-energy technologies through agreements such as the six-nation Asia–Pacific partnership. Yet many of Bush's core supporters are religious conservatives.

Evangelicals are a powerful social force in the United States, with the National Association of Evangelicals (NAE) boasting 30 million members. ‘Evangelical’ is an umbrella term encompassing more than 50 denominations whose members typically believe in Jesus Christ and that the Bible is the authoritative word of God. The NAE has not officially endorsed the climate initiative, but many of the organization's leaders believe it represents a growing consensus that climate change is a matter for concern.

Climate-induced changes in sea level are seen by many evangelicals as having a moral dimension. Credit: P. JOHNSON/CORBIS

Climate researchers are watching the movement with optimism. Jim White, a University of Colorado geochemist who studies ice sheets in Greenland, says that it will almost certainly accelerate public support for action on climate change. “To have a group that has historically fought the notion come around — I think that does impact on the public's thinking,” he says.

And it is this public support that some believe could influence conservative legislators. Eileen Claussen, president of the Pew Center on Global Climate Change, based in Arlington, Virginia, says that the lack of significant public demand for action on climate has hampered acceptance by members of Congress. “So I think the evangelical initiative is welcomed by all,” she adds.

To have a group that has historically fought the notion come around does impact on the public's thinking.

One reason many are hopeful about change is that certain key evangelicals — such as Ted Haggard, president of the NAE, and Richard Cizik, the group's vice-president of government affairs — speak regularly with the White House. “That's very significant,” says DeWitt. “I think the president really wants evangelicals to see him as evangelical.” If Bush does not warm to the idea of mandatory emissions, DeWitt says, he could lose some of his key support.

Backers of the initiative are now distributing the statement to Congress, hoping to educate legislators on their views. “They may be able to hear the message about climate change from us where they couldn't necessarily hear it and really listen to it from others,” says Reverend Jim Ball, executive director of the Evangelical Environmental Network, which is championing the initiative.

A positive development would be to bring together two bipartisan groups of senators — one led by John McCain (Republican, Arizona) and Joe Lieberman (Democrat, Connecticut), and the other by Pete Domenici (Republican, New Mexico) and Jeff Bingaman (Democrat, New Mexico) — who have separately put forward climate-change legislation. Domenici and Bingaman have scheduled an April congressional climate conference to discuss ways of mandating emissions cuts.

The evangelicals say they realize they won't change minds overnight. “We're under no illusions that our statement, or its circulating, is going to break open the log jam,” says Ball. In the meantime, the group is airing advertisements on major television networks. They next aim to build relationships within the business community, in part by planning for a November meeting between business leaders and evangelicals to help show that climate change can be tackled in ways that will not harm the economy.

John Houghton, a leader in the Christian environmental movement (see ‘The man who preaches science’), says the task is particularly hard in the United States. He lectures frequently to international audiences and says that, outside the United States, he rarely encounters resistance to the validity of climate-change science. But leaders of the initiative feel the science is now solid enough to convince even the unbelievers. “If there was not such an overwhelming scientific consensus, we probably wouldn't be able to get traction on this issue in our community,” says Ball.