HONG KONG (Reuters) - Biofuels are likely to speed up global warming as they are encouraging farmers to burn tropical forests that have absorbed a large portion of greenhouse gases, climate scientists warned.
The specialists, who gathered for an international conference in Hong Kong, rang the alarm bell as Malaysian palm oil futures prices hit all-time highs this week, helped by new demand for the vegetable oil from the biodiesel sector.
"Some of these alternative energy schemes, such as biofuels, are truly dangerous," said James Lovelock, an independent scientist known for the Gaia theory.
"If exploited on a large scale, they will hasten our downfall," he said in a video message delivered from Oxford.
Preserving tropical forests is seen as key to mitigating global warming caused by greenhouse gases, as they capture a large volume of carbon dioxide emissions.
In Asia, home to the world's top oil palm producers such as Malaysia and Indonesia, there has been an investment boom in biodiesel plants, which convert palm oil into biodiesel for cars.
This has helped to push up prices for palm oil -- the cheapest vegetable oil -- by 25 percent so far this year. Prices had risen by 40 percent in 2006.
Chinese investors are also looking into building palm-based biodiesel plants in Indonesia or Papua New Guinea as Beijing promotes biofuels to cut the country's dependence on imported oil, although it already has a big deficit in vegetable oils.
"The big issue, particularly in Southeast Asia, is oil palm plantations. It is expanding rapidly for biofuels," said Simon Lewis from School of Geography, Earth & Biosphere Institute at University of Leeds.
"The likelihood is it will increase deforestation," he said. "It is said this can be regulated. But most tropical forest is essentially unregulated."
Lewis also said forest fires often caused by farmers were an additional danger for global warming, to which the international community had not paid enough attention.
"With the climate change, with periodic droughts, more of tropical forests is possible to burn," he said.
"People will set fire to forests if they can because they want to clear the forest for oil palm plantations."
The scientist said a record 2 billion metric tons of carbon went up into the atmosphere from fires in Indonesia alone during the El Nino in 1997/1998, in addition to usual emissions of 1 billion to 2 billion metric tons worldwide.
"The El Nino year of 1997/98 with massive burning across the tropics, record-breaking temperatures, carbon dioxide concentration may become a dangerously common feature in the coming decades," he said.