Emerging El Nino set to drive up carbon emissions

By David Fogarty, Climate Change Correspondent, Asia

SINGAPORE (Reuters) - Across the globe an emerging El Nino weather pattern threatens to cause droughts and floods and trigger a spike in planet-warming greenhouse gas emissions from burning forests.

El Nino is a warming of tropical Pacific waters that affects wind circulation patterns. Its effects on the global climate vary from one event to the next.

Trying to predict how El Nino will be affected by global warming is a major challenge, scientists say, although data shows El Ninos have become more frequent and more intense over the past three decades. The last event was in 2006.

"I don't think there are any studies that are saying El Nino will become less severe but there is disagreement among the climate models on whether they will become more severe or stay steady," said Matthew England of the Climate Change Research Center in Sydney.

Getting the forecasting right is crucial for farmers in planning their crops, and even for the oil industry in assessing storm risks in the Gulf of Mexico.

"Certainly we know from past climates that El Nino intensity has varied. As climate changes, we know that the intensity of El Nino can wax and wane over long time scales," he said.

Australia's Bureau of Meteorology said last week an El Nino was almost certain this year and the signs point to one already well underway. A formal declaration could be within days.

(For more details see the bureau's website at: www.bom.gov.au/climate/enso/)

One of the biggest threats from El Nino comes from the release of vast amounts of greenhouse gases through the burning of dried out forests.

Scientists say there is very strong correlation between El Nino and drought in Southeast Asia, which has large areas of carbon-rich peat forests.

"People are waiting for appropriate conditions to get rid of the forests," said Pep Canadell of the Global Carbon Project in Canberra.

"So the drier the El Nino the more incentive there is for people to take advantage of those unique conditions," he said. Most of the burning occurs in Indonesia.

SPIKE IN TEMPERATURES

During the very intense El Nino of 1997/98, fires in Southeast Asia released between 2.9 billion 9.4 billion metric tons of CO2, blanketing the region in a choking haze. The smoke equated to between 15 and 40 percent of global fossil fuel emissions and is credited with causing a spike in global temperatures.

By comparison, average annual emissions from forest fires in Southeast Asia between 2000 and 2006 were 470 million metric tons of CO2, while average fossil fuel emissions for the same period in the region were 543 million metric tons of CO2, said Canadell.