The report says there are environmentally safe ways to avoid the dangerous effects of climate change simply by using technologies that are available today.

But the international director of the WWF, James Leape, tells VOA action must be taken quickly. He believes disastrous climate changes can be prevented only if governments act within the next five years to implement solutions.

"It is possible for us to begin, if we take bold action now, to begin to see total global emissions peak and to begin to come down within the next 10 years. That is what needs to happen. What that requires from countries like the United States is a very aggressive investment in energy efficiency, to get much more out of the energy we do use and a very aggressive investment in developing renewable sources of energy as well as carbon …storage. If we do that now, not six or eight or 10 years from now, but now, we can actually begin to turn the corner in the next decade," said Leape.

The WWF report maps out a path for meeting the challenge of climate change. It says there is no one solution. Rather action has to be taken on multiple fronts.

This includes the development of greater energy efficiency policies and the expansion of renewable energy sources such as wind and solar power. It also calls for the capture of carbon emitted by burning fossil fuels and storing it underground so it does not contribute to climate change.

The report says bio-fuels can, potentially, play a significant role. But they have to be managed so they are sustainable. For example, Leape says the aggressive development of corn offers little benefit for the climate because too much carbon is produced in the course of producing ethanol. And he says there are two other reasons to be cautious about biofuels.

"A second is that they can have serious environmental consequences. The demand for some bio-fuels threatens to drive greatly expanded rain forest clearing for example. And, a third problem is that … the demand for bio-fuels may compete with demand for food and cause problems of food security around the world. So, we need to be thoughtful about bio-fuels," said Leape.

The WWF report is opposed to the expansion of nuclear power as a solution for climate change. It says concerns about plant safety, waste disposal and the possible proliferation of nuclear technology are risks too great to take.

It also says nuclear power would divert resources from much more promising and cost-effective solutions, such as renewable technologies.