While national carbon cap-and-trade efforts face opposition from business and industry groups at home, more than 500 business leaders meeting in Copenhagen over the weekend say they're ready to support "immediate and substantial change" aimed at beginning an overall reduction in greenhouse gas emission in the next 10 years.

That's the gist of a statement released Tuesday from the World Business Summit on Climate Change, a meeting meant to rally business support for the December international meeting in Copenhagen that is meant to come up with a treaty to succeed the Kyoto Protocol.

"The Copenhagen Call" document laid out six points which the group seeks to see included in that treaty, meant to help governments craft policies to reduce greenhouse gas emissions and curb the threat of global warming.

The first step calls for an agreement on "science-based" targets for cutting greenhouse gas emissions by 17 gigatons compared to a "business as usual" scenario by 2020, with the goal of limiting global average temperature increased to no more than 2 degrees Celsius by 2050.

"Emissions reduction at this scale will profoundly affect business," the document conceded. But, "If policies are well designed and implemented, the benefits of early action will outweigh the short-term adjustment costs," the document added.

That's based on the group's acceptance of the threats of climate change as laid out by the U.N. Intergovernmental Panel on Climate Change, as well as newer science that paints an even more dire picture for the future of the globe's climate (see Climate Change: Best-Case Scenarios Still Threaten Coasts).

The group also called for the upcoming treaty to include "unified, coherent and reliable measurement, reporting and verification" of greenhouse gas emissions by industry, incentives to boost development and deployment of low-emissions technologies, funds to help communities become "more resilient" to climate change and support for protecting forests and agricultural lands as storehouses of atmospheric carbon dioxide.

The summit's participants included a hodgepodge of players, including major utilities such as Denmark's Dong Energy, Sweden's Vattenfall and the United States' Duke Energy, renewable power powerhouses such as Vestas, Alstom and Suntech Power, green tech startups like Better Place and Novozymes and large industrial companies such as PepsiCo, Unilever and Swiss Re.

The statement comes as governments around the world are facing some stiff opposition to carbon cap-and-trade schemes on the grounds that they will cripple the economy as it seeks to emerge from the ongoing global recession.

Australia this month said it would delay by one year its implementation of its cap-and-trade scheme, which would set greenhouse gas emissions limits and force businesses that exceed those limits to buy permits from those that cut emissions below those limits (see Australia Delays Cap-and-Trade Program, No Surprise There).

Europe has had a cap-and-trade system in place since 2005, though its effect in curbing emissions has been challenged. European Union efforts to expand the system have been opposed from countries such as Poland that are more dependent on coal-generated power (see U.N. Climate Talks Pose Big Impact on Greentech).

In the United States, environmental groups have reacted with dismay to what they call concessions to industry in a climate bill working its way through Congress (see House Energy Bill Draft: Cap-and-Trade Included).

Those include a plan to give away 15 percent of the permits free to what it calls "energy-intensive, trade-exposed industries" such as steel and cement, rather than auctioning off all the permits (see Come Get 'Em: Gov't Plans to Give Freebies Under Cap-and-Trade).

The cap-and-trade portion of that energy and climate bill, introduced by Henry Waxman, D-Calif., and Edward Markey, D-Mass., has the support of President Barack Obama and key Congressional leaders, who hope to see it passed into law by year's end so the United States can present it to international leaders in Copenhagen.

But some observers have cast doubt over whether cap-and-trade provisions will survive, given industry opposition.