(AP) -- An international treaty on climate change won't be enough to avert a dangerous rise in global temperatures, and countries need to voluntarily make deeper cuts in carbon emissions, the head of the U.N. Environment Program said Tuesday.
A UNEP report, released last month and formally presented on Tuesday to South Africa, the host government of the 194-nation U.N. climate conference, said the world is losing ground in controlling heat-trapping greenhouse gases.
"We are not moving fast enough," said UNEP chief Achim Steiner. "We are losing time."
A legal treaty with binding targets and voluntary measures by all countries is needed to keep the Earth from gaining more than 3.6 degrees Fahrenheit (2 degrees Celsius) by the end of the century.
That could be achieved with investments in clean energy and other measures to tackle emissions, Steiner said. But warned the investments would reduce the global rise of GDP by 0.2 percent.
Later Tuesday, U.N. Secretary General Ban Ki-moon will open the decisive ministerial stage of the two-week climate conference in Durban which is focused on efforts to move toward a future agreement to legally bind all nations to emissions targets, including China and the United States.
The conference also needs to settle the details of a climate fund to help poor countries adapt to changing weather patterns and move to low-carbon growth. The fund is meant to scale up to $100 billion annually by 2020, from $10 billion now.
Twelve presidents or heads of government and about 130 cabinet ministers are attending the final days of the conference, which will close Friday.
Updated research released Tuesday by the independent group Ecofys reinforced UNEP's report that the gap is widening between pledges by nations to reduce greenhouse gases and the targets set by scientists for preventing runaway global warming.
More than 80 countries have submitted plans to either reduce emissions or slow their growth, but Ecofys says those pledges would lead to global emissions of 55 gigatons of carbon dioxide and other gases annually by 2020 - 11 gigatons more than what scientists say would be relatively safe. That's more than twice the amount of emissions by all of Europe in one year, said Niklas Hohne, a lead author of the report.
"The longer one waits, the more difficult it will be," Hohne said in an interview. At the current pace, average global temperatures will rise by 6.3 F (3.5 C), the report said.
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