Climate ‘adds fuel to Asian wildfire emissions’


In the last decade, Asian farmers have cleared tens of thousands of square miles of forests to accommodate the world’s growing demand for palm oil, an increasingly popular food ingredient, reports Science Daily.

Ancient peatlands have been drained and lush tropical forests have been cut down.

As a result, the landscape of equatorial Asia now lies vulnerable to fires, which are growing more frequent and having a serious impact on the air as well as the land.

A team of NASA-sponsored researchers have used satellites to make the first series of estimates of carbon dioxide (CO2) emitted from these fires — both wildfires and fires started by people — in Malaysia, Indonesia, Borneo, and Papua New Guinea.

They are now working to understand how climate influences the spread and intensity of the fires.

Using data from a carbon-detecting NASA satellite and computer models, the researchers found that seasonal fires from 2000 to 2006 doubled the amount of carbon dioxide (CO2) released from the Earth to the atmosphere above the region.

The scientists also observed through satellite remote sensing that fires in regional peatlands and forests burned longer and emitted ten times more carbon when rainfall declined by one third the normal amount.

The results were presented in December 2008 in Proceedings of the National Academy of Sciences.

Tropical Asian fires first grabbed the attention of government officials, media, and conservationists in 1997, when fires set to clear land for palm oil and rice plantations burned out of control.

The fires turned wild and spread to dry, flammable peatlands during one of the region’s driest seasons on record. By the time the flames subsided in early 1998, emissions from the fires had reached 40 percent of the global carbon emissions for the period.

“In this region, decision makers are facing a dichotomy of demands, as expanding commercial crop production is competing with efforts to ease the environmental impact of fires,” said co-author Jim Collatz, an Earth scientist at NASA’s Goddard Space Flight Center.

“The science is telling us that we need strategies to reduce the occurrence of deforestation fires and peatlands wildfires. Without some new strategies, emissions from the region could rise substantially in a drier, warmer future.”

Since the 1997 event, the region has been hit by two major dry spells and a steady upswing in fires, threatening biodiversity and air quality and contributing to the buildup of CO2 in the atmosphere.

As more CO2 is emitted, the global atmosphere traps more heat near Earth’s surface, leading to more drying and more fires.

Until recently, scientists knew little about what drives changes in how fires spread and how long they burn. Dr Collatz, along with lead author Guido van der Werf of Vrije University, Amsterdam, and other colleagues sought to estimate the emissions since the devastating 1997-98 fires and to analyse the interplay between the fires and drought.

They used the carbon monoxide detecting Measurements of Pollution in the Troposphere (MOPITT) instrument on NASA’s Terra satellite — as well as 1997-2006 fire data and research computer models — to screen for and differentiate between carbon emissions from deforestation versus general emissions.

Carbon monoxide is a good indicator of the occurrence of fire, and the amounts of carbon monoxide in fire emissions are related to the amount of carbon dioxide.

They also compared the emissions from different types of plant life (peat land verses typical forest) by examining changes in land cover and land use as viewed by Terra’s Moderate Resolution Imaging Spectradiometer (MODIS) and by Landsat 7.

Collatz explained that two climate phenomena drive regional drought.

El Nino’s warm waters in the Eastern Pacific change weather patterns around the world every few years and cause cooler water temperatures in the western Pacific near equatorial Asia that suppress the convection necessary for rainfall.

Previously, scientists have used measurements from NASA’s Tropical Rainfall Measurement Mission satellite to correlate rainfall with carbon losses and burned land data, finding that wildfire emissions rose during dry El Nino seasons.

The Indian Ocean dipole phenomenon affects climate in the Indian Ocean region with oscillating ocean temperatures characterized by warmer waters merging with colder waters to inhibit rainfall over Indonesia, Borneo, and their neighbors.

“This link between drought and emissions should be of concern to all of us,” said co-author Ruth DeFries, an ecologist at Columbia University in New York.

“If drought becomes more frequent with climate change, we can expect more fires.”

Collatz, DeFries, and their colleagues found that between 2000 and 2006, the average carbon dioxide emissions from equatorial Asia accounted for about 2 percent of global fossil fuel emissions and 3 percent of the global increase in atmospheric CO2.

But during moderate El Nino years in 2002 and 2006, when dry season rainfall was half of normal, fire emissions rose by a factor of 10. During the severe El Nino of 1997-1998, fire emissions from this region comprised 15% of global fossil fuel emissions and 31% of the global atmospheric increase over that period.

“This study not only updates our measurements of carbon losses from these fires, but also highlights an increasingly important factor driving change in equatorial Asia,” explained DeFries.

“In this part of Asia, human-ignited forest and peat fires are emitting excessive carbon into the atmosphere. In climate-sensitive areas like Borneo, human response to drought is a new dynamic affecting feedbacks between climate and the carbon cycle.”

In addition to climate influences, human activities contribute to the growing fire emissions.

Palm oil is increasingly grown for use as a cooking oil and biofuel, while also replacing trans fats in processed foods.

It has become the most widely produced edible oil in the world, and production has swelled in recent years to surpass that of soybean oil.

More than 30 million tonnes of palm oil are produced in Malaysia and Indonesia alone, and the two countries now supply more than 85% of global demand.

The environmental effects of such growth have been significant. Land has to be cleared to grow the crop, and the preferred method is fire.

The clearing often occurs in drained peatlands that are otherwise swampy forests where the remains of past plant life have been submerged for centuries in as much as 60 feet of water.

Peat material in Borneo, for example, stores the equivalent of about nine years worth of global fossil fuel emissions.

“Indonesia has become the third largest greenhouse gas emitter after the United States and China, as a result primarily to these fire emissions,” Collatz said.

“With an extended dry season, the peat surface dries out, catches fire, and the lack of rainfall can keep the fires going for months.”

Besides emitting carbon, the agricultural fires and related wildfires also ravage delicate ecosystems in conservation hotspots like the western Pacific island of Borneo, home to more than 15,000 species of plants, 240 species of trees, and an abundance of endangered animals.

Smoke and other fire emissions also regularly taint regional air quality to such a degree that officials have to close schools and airports out of concern for public health and safety.

Peat fires also aggravate air pollution problems in this region because they release four times more carbon monoxide than forest fires.

In 1997, air pollution from the fires cost the region an estimated $4.5 billion in tourism and business.

Source: Science Daily

Date: 10/05/2009

Study links forest fires to climate shift


A warming climate will fuel larger, more frequent wildfires in the Sierra Nevada and other parts of the West, and the fires will contribute to climate change, according to a new study reported in Insurance Journal.

More than 20 international scientists, in the report published in the journal Science, said fire is not only a consequence of climate change but an important cause.

“Fire also influences the climate system. This is what we call a feedback,” Jennifer Balch, a fire expert at the University of California, Santa Barbara, told the Reno Gazette-Journal.

Scientists determined intentional deforestation fires, many set in tropical areas to expand agriculture or ranching, contribute up to a fifth of the human-caused increase in emissions of carbon dioxide, a heat-trapping gas helping to boost global temperatures.

The researchers called on the Intergovernmental Panel on Climate Change (IPCC) to fully integrate fire into its ongoing assessment of climate change.

Fire-climate feedbacks, they said, have been largely absent from global climate models.

“Extraordinary (fires are) occurring like a rash all over the planet,” said David Bowman, a forestry and wildlife expert at the University of Tasmania.

Fire of unprecedented ferocity swept across parts of Australia in February, killing about 200 people.

Similar fire activity can be expected elsewhere as the climate warms, including in the Sierra, where a 2007 blaze at Lake Tahoe destroyed 254 homes, scientists said.

“We are witnessing an increasing amount of so-called megafires,” said Thomas Swetnam, an expert on fire history and forest ecology at the University of Arizona. “Unfortunately, I think we are going to see more large fires in the western United States. The western United States is in a bull’s-eye.”

Swetnam was involved in a 2006 study that indicated increased fire activity is associated with increasing spring and autumn temperatures and an earlier spring snowmelt in western mountains.

That study found that wildfire frequency spiked to nearly four times the average experienced from 1970 to 1986, with the area burned more than six times previous levels.

The average length of the fire season increased by 78 days between 1987 and 2003 compared with 1970 to 1986, with fires starting earlier and burning later into the season.

Source: Insurance Journal

Date: 30/04/2009

Wildlife flee Kenyan forest fires


Hundreds of thousands of flamingos and other wildlife are at risk after five forest fires erupted in Kenya on Saturday, say wildlife officials.

The BBC News website reports that police say they suspect some of the still-raging blazes were started by communities to make space for farmland.

The fires have had an adverse effect on the Masai Mara and in Tanzania on the Serengeti national park, officials say.

Other wildlife reserves are under threat, including Lake Nakuru, which is home to almost a million flamingos.

According to the Kenya Wildlife Service (KWS), all the rivers that drain from south-western Kenya’s Mau forest into the lake have dried drastically.

Nearly 60 species of wildlife, including white rhino, depend on the lake.

By Sunday an estimated 200 hectares (500 acres) of woodland had been razed in Mau – East Africa’s largest indigenous forest.

KWS communications manager Paul Udoto told the BBC: “We now have to pump water from underground bore holes to shallow pans to water the animals in the park otherwise they will all die. This is costing us a lot of money.”

Members of communities opposed to government plans to move them out of the Mau forest are suspected, say police, and several people have been arrested, accused of arson.

Another blaze nearby has destroyed about a quarter of the 52 sq km (20 square miles) Mount Longonot National Park, an extinct volcano in Kenya’s Rift Valley, said officials.

Zebras, buffaloes, antelopes, gazelles and giraffes have fled the fires, crossing roads and residential areas to reach safety, said witnesses.

But some wildlife experts said snakes and smaller animals, like rabbits and mongooses, may not have managed to escape.

Kenya is suffering a drought this year that has contributed to hunger the government says is affecting 10 million people.

Source: BBC News website

Date: 23/03/2009

Forest fires ‘to add to climate concerns’


The fierce bushfires that scorched Australia’s Victoria State released millions of tonnes of carbon dioxide, a leading scientist has warned.

Forest fires could become a growing source of carbon pollution as the planet warms, he told Reuters news agency.

Mark Adams of the University of Sydney said global warming could trigger a vicious cycle in which forests could stop becoming sinks of CO2, further accelerating the rise of the planet-warming gas in the atmosphere.

“With increasing concerns about rising CO2, rising temperatures and reduced rainfall in many of the forested areas, then we could well see much greater emissions from forest fires,” added Professor Adams, dean of the Faculty of Agriculture, Food and Natural Resources.

The Victoria fires, which killed more than 200 people, were the worst in the nation’s history and many were still burning weeks later.

“Scientists worldwide are worried about fires and forests.

“It doesn’t matter if it’s the Arctic tundra fires, or peat fires in Kalimantan or bushfires in Australia,” observed the Australian researcher, who has worked in collaboration with the Bushfire Co-operative Research Centre.

In a submission to the United Nations last year, the Australian government said wildfires in 2003 released 190 million tonnes of CO2-equivalent, roughly a third of the nation’s total greenhouse gas emissions for the year.

Such large, one-off releases of CO2 and other greenhouse gases such as methane, are not presently accounted for in Australia’s annual list of national greenhouse gas emissions.

If they were, the country would vastly exceed its emission limits under the Kyoto Protocol, the United Nations’ main weapon to fight climate change.

This is one reason, critics say, why Australia is calling for amendments to UN rules on land use change, so that only human activities that “can be practicably influenced” are included.

Professor Adams said the UN climate summit at the end of the year in Denmark should discuss the growing threat from forest fires and how to develop better legal frameworks to tackle the problem.

In a study of how much carbon Australia’s forests and soil can store, he estimated that fires in 2003, which ravaged the capital Canberra, and in 2006-07 released about 550 million tonnes of CO2.

The current fires had already burned hundreds of thousands of hectares, he said, in areas with total carbon content of 200 tonnes per hectare or more.

Australia, though, was not his only concern; annual fires in Indonesia also release vast amounts of CO2.

Huge fires in 1997 released up to 6 billion tonnes of CO2, covering South-East Asia in a thick haze and causing a spike in global levels of the gas.

Research on the forest and peat fires by a team of international scientists found the blazes released the equivalent of up 40% of global annual emissions from burning fossil fuels.

Professor Adams described the findings as a “wake-up call”.

“When you see the step-increases (of CO2) that they observed, we have to sit up and take notice, that fires are a major problem,” he said.

In the past, he explained, native forest carbon had been in rough equilibrium over millions of years with fires, with very small accretion of carbon over very long periods of time.

“But then if you add rapid climate change and much greater fire frequency, the equilibrium carbon content of the native forests, instead of going up, is going to go down.”

Source: Reuters


Date: 26/02/2009

Human activity ‘triggers rise in Borneo forest fires’


Severe fires in Indonesia – responsible for some of the worst air quality conditions worldwide – are linked not only to drought, but also to changes in land use and population density, according to a new study in Nature Geoscience.

“During the late 1970s, Indonesian Borneo changed from being highly fire-resistant to highly fire-prone during drought years, marking the period when one of the world’s great tropical forests became one of the world’s largest sources of pollution,” said lead researcher Robert Field, a PhD student of atmospheric physics at the University of Toronto, Canada.

“Ultimately, this abrupt transition can be attributed to rapid increases in deforestation and population growth,” he explained.

“The resulting occurrences of haze currently rank among the world’s worst air pollution episodes, and are a singularly large source of greenhouse gas emissions.”

Sumatra has suffered from large fires since at least the 1960s, but Indonesian Borneo seems to have been resistant to large fires, even in dry years, until population density and deforestation increased substantially and land use changed from small-scale subsistence agriculture to large-scale industrial agriculture and agro-forestry.

“We’ve had a good understanding of fire events since the mid 1990s, but little before this due to the absence of fire data from satellites,” said Mr Field.

“However, one of the major impacts of large-scale fires is a reduction in visibility due to the smoke produced.

“Visibility is recorded several times a day at airports in the region, and these records proved to be an excellent indicator of severe fire activity.

“We were able to piece together visibility observations back to the 1960s, and hence develop a longer term record of the fires.”

Having a long-term record of the fires allowed the scientists to better understand their causes.

“Using weather records, we were able to estimate the specific rainfall level below which large fires have occurred in the previous two decades,” Mr Field added.

“In turn, we found that the rainfall over Indonesia was influenced equally by the Indian Ocean Dipole and the El Nino Southern Oscillation phenomena.”

Mr Field concluded: “Hopefully, this information can be used to better anticipate and prevent future haze disasters in Indonesia.”

He said that there was a direct link between the increased prevalence of severe fires and haze disasters and the man-made change in land use.

“The visibility record also showed, quite strikingly, the impact of human settlement on a previously pristine tropical forest.

“This should give pause to further agro-forestry expansion in Indonesia, particularly for oil palm as a source of biofuel.”

Source: EurekAlert

Date: 22/02/2009

Australian bushfires raise questions over forest strategies


Fire experts say inadequate fuel reduction strategies in Victoria’s forests may have contributed to the weekend disaster, The Age reports.

Rapid population growth on Melbourne’s fringes may also have been a factor in the high toll, one expert said.

But as Victoria reeled in disbelief at the scale of the disaster, most debate centred on whether to review the decades-old policy of allowing people to defend their homes.

Announcing a Royal Commission, the state’s premier, John Brumby, said the policy of “leave early or stay and defend property” would come under scrutiny.

“It’s served us well for 20 years or more,” Mr Brumby told Radio 3AW. “It’s not true to say that of the fire on Saturday.

“There were many people who had done all of the preparations, had the best fire plans in the world and tragically it didn’t save them.”

But former police ministers Andre Haermeyer and Pat McNamara dismissed one of the alternatives to “stay and fight”, which are forced evacuations.

Mr Haermeyer said that many of the people that had been killed in the fires has been as prepared as they could have been.

“This fire turned so quickly and with such a force, you wonder what systems, what procedures could have given people the chance to get out,” he said.

Mr McNamara added that many people appeared to have died fleeing the bushfires by car, a situation that could have been made worse by forced evacuations.

He said more clearing of native vegetation should be allowed to create a larger buffer between houses and fires.

A former chief of community safety, Naomi Brown, said forced evacuations in the face of bushfires were a simplistic response that could put people in more danger.

“You could have said to everybody on Friday you have to move out, but you don’t know where the fire is going to be,” she said.

Ms Brown, who is chief executive at the Australasian Fire and Emergency Services Authorities Council, warned about jumping to conclusions on fire policy while the fires still burned across Victoria.

“There are a lot of opinions and assumption, but not a lot in the way of evidence,” she said.

One reason why the death toll at the weekend was worse than “Ash Wednesday” (4 Feb 2009), she said, was the increase in people living on the outskirts of Melbourne in the past 25 years.

Fire and community safety experts have raised questions about whether the amount of fuel in the bush in some areas, such as Kinglake, worsened the impact of the fires.

Monash University research fellow and bushfire specialist David Packham laid much of the blame for the devastation on extremely high fuel loads in Victorian forests.

“There has been total mismanagement of the Australian forest environment,” he said.

Source: The Age website

Date: 10/02/2009

Amazon rainfall projections ‘underestimated’


Amazonian forests may be less vulnerable to dying off from global warming than feared because many projections underestimate rainfall, Reuters reports.

A study by UK researchers suggested that Brazil and other nations in the region would also have to act to help avert any irreversible drying of the eastern Amazon, the region most at risk from climate change, deforestation and fires.

“The rainfall regime in eastern Amazonia is likely to shift over the 21st Century in a direction that favours more seasonal forests rather than savannah,” the team write in the journal Proceedings of the National Academy of Sciences.

Seasonal forests have wet and dry seasons rather than the current rainforest, which is permanently drenched.

It is argued that this shift in precipitation patterns could result in the emergence of new species of trees, other plants and animals.

The findings challenge past projections that the Amazon forest could die and be replaced by savannah.

The Intergovernmental Panel on Climate Change reported in 2007: “By mid-century, increases in temperature and associated decreases in soil water are projected to lead to gradual replacement of tropical forest by savannah in eastern Amazonia.”

The new study said that almost all of 19 global climate models underestimated rainfall in the world’s biggest tropical forest.

Lowland forests in the Amazon have annual average rainfall of 2,400 mm (94 inches), it said.

Projected cuts in rainfall meant the region would still be wet enough to sustain a forest.

The experts also examined field studies of how the Amazon might react to drying.

It said that seasonal forests would be more resilient to the occasional drought but more vulnerable to fires than the current rainforest.

“The fundamental way to minimise the risk of Amazon dieback is to control greenhouse gas emissions globally, particularly from fossil fuel combustion in the developed world and Asia,” said Yadvinder Malhi, the lead author from Oxford University.

But he said that governments led by Brazil also needed to improve their forest management policies.

Global warming is “accompanied by an unprecedented intensity of direct pressure on the tropical forests through logging, deforestation, fragmentation, and fire use,” the scientists wrote.

And fires, including those touched off by lightning, were more likely to cause wide damage to forests already fragmented by roads or by farmers clearing land to plant crops, such as soya beans.

Source: Reuters

Date: 09/02/2009

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