Reuters
Friday 28 September 2007
New York - Primate scientist Jane Goodall said on Wednesday the race to grow crops for vehicle fuels is damaging rain forests in Asia, Africa and South America and adding to the emissions blamed for global warming.
"We're cutting down forests now to grow sugarcane and palm oil for biofuels and our forests are being hacked into by so many interests that it makes them more and more important to save now," Goodall said on the sidelines of the Clinton Global Initiative, former US President Bill Clinton's annual philanthropic meeting.
As new oil supplies become harder to find, many countries such as Brazil and Indonesia are racing to grow domestic sources of vehicle fuels, such as ethanol from sugarcane and biodiesel from palm nuts.
The United Nations' climate program considers the fuels to be low in carbon because growing the crops takes in heat-trapping gas carbon dioxide.
But critics say demand for the fuels has led companies to cut down and burn forests in order to grow the crops, adding to heat-trapping emissions and leading to erosion and stress on ecosystems.
"Biofuel isn't the answer to everything; it depends where it comes from," she said. "All of this means better education on where fuels are coming from are needed."
Goodall said the problem is especially bad in the Indonesian rain forest where large amounts of palm nut oil is being made. Growers in Uganda - where her nonprofit group works to conserve Great Apes - are also looking to buy large parcels of rain forest and cut them down to grow sugar cane, while in Brazil, forest is cleared to grow sugar cane.
The Goodall Institute is working with a recently formed group of eight rain forest nations called the Forest Eight, or F8, led by Indonesia. The group wants to create a system where rich countries would pay them not to chop down rain forests and hopes to unveil the plan at climate talks in Bali in December.
Scientists from the forested countries are trying to nail down exactly how much carbon dioxide the ecosystems store, but the amount has been estimated to be about double that which is already in the atmosphere, Goodall said.
Many Biofuels Have More Climate Impact Than Oil
By Emma Graham-Harrison
Reuters
Friday 28 September 2007
Beijing - Most crops grown in the United States and Europe to make "green" transport fuels actually speed up global warming because of industrial farming methods, says a report by Nobel prize winning chemist Paul J. Crutzen.
The findings could spell particular concern for alternative fuels derived from rapeseed, used in Europe, which the study concluded could produce up to 70 percent more planet-warming greenhouse gases than conventional diesel.
The study suggested scientists and farmers focused on crops, which required less intensive farming methods, to produce better benefits for the environment.
Biofuels are derived from plants which absorb the planet-warming greenhouse gas carbon dioxide as they grow, and so are meant as a climate-friendly alternative to fossil fuels.
But the new study shows that some biofuels actually release more greenhouse gases than they save, because of the fertiliser used in modern farming practices.
The problem greenhouse gas, nitrous oxide, is more famous as the dentists' anaesthetic "laughing gas," and is about 300 times more insulating than the commonest man-made greenhouse gas carbon dioxide.
"The nitrous oxide emission on its own can cancel out the overall benefit," co-author Professor Keith Smith told Reuters in a phone interview.
The results, published in "Atmospheric Chemistry and Physics Discussions," were based on the finding that fertiliser use on farms was responsible for three to five times more such greenhouse gas emissions than previously thought.
They cast further doubts on the credibility of biofuels as a climate cure, following the revelation of other unintended side effects such as rainforest clearance and raised food prices, from competition with forests and food for land. Brazil and the United States produce most of the world's bioethanol, as a substitute for gasoline, while the European Union is the main supplier of biodiesel.
"Futile Exercise"
Using biodiesel derived from rapeseed would produce between 1 and 1.7 times more greenhouse gas than using conventional diesel, the study estimated.
Biofuels derived from sugar cane, as in Brazil, fared better, producing between 0.5 and 0.9 times as much greenhouse gases as gasoline, it found.
Maize is the main biofuels feedstock used in the United States, and produced between 0.9 and 1.5 times the global warming effect of conventional gasoline, it said.
"As it's used at the moment, bioethanol from maize seems to be a pretty futile exercise," Smith said.
The study did not account for the extra global warming effect of burning fossil fuels in biofuel manufacture, or for the planet-cooling effect of using biofuel by-products as a substitute for coal in electricity generation.
"Even if somebody decides that our numbers are too big ... if you add together the undoubted amount of nitrous oxide that is formed, plus the fossil fuel usage, with most of the biofuels of today you are not going to get any benefit," Smith said.
However, the study did not condemn all biofuels, suggesting that scientists and farmers should focus on crops needing little fertiliser, and harvesting methods that were not energy intensive.
"In future if you use low nitrogen demanding crops, and low impact agriculture, then we could get a benefit," Smith said.
The study singled out grasses and woody coppice species - like willows and poplars - as crops with potentially more favourable impacts on the climate.
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