Reducing tropical deforestation by 50 percent over the next century would help prevent 500 billion tonnes of carbon from going into the atmosphere every year, the researchers said in a policy article published in the journal Science Express.

Such a reduction in emissions would account for 12 percent of the total reductions targeted by the United Nations' Intergovernmental Panel on Climate Change, the researchers said.

At its current rate, tropical deforestation releases annually 1.5 billion tonnes of carbon into the atmosphere that would otherwise be absorbed by trees, making it a major contributor to global climate change, they said.

The policy article was aimed to give scientific and technological backing to a two-year initiative launched by the United Nations Framework Convention on Climate Change, after a group of developing nations asked for a strategy to make forest preservation politically and economically attractive.

The researchers said the Reducing Emissions from Deforestation (RED) initiative faces political challenges as many developing countries consider their tropical forests as a key economic resource.

But low-cost measures could be taken to convince developing nations to reduce deforestation, including, for example, by helping them evaluate the use of forests to focus clearing only in areas with high agricultural value, they said.

"It will require political will and sound economic strategy to make the RED initiative work," said Christopher Field, director of the Global Ecology Department at the Carnegie Institution of Washington, a private, non-profit scientific research organization.

"But the initiative provides a big reduction in emissions at low cost," he said in a statement.

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