Revenge of the rainforest

Photograph by George Grall – Amazon horned frog – Ceratophrys cornuta – Source:National Geographic

The Amazon has long been the lungs of the world. But now comes dramatic evidence that we cannot rely on it in the fight against climate change.

Source: The Independent UK

By Steve Connor
Friday, 6 March 2009

It covers an area 25 times bigger than Britain, is home to a bewildering concentration of flora and fauna and is often described as the “lungs of the world” for its ability to absorb vast amounts of carbon dioxide through its immense photosynthetic network of trees and leaves.

The Amazon rainforest is one of the biggest and most important living stores of carbon on the planet through its ability to convert atmospheric carbon dioxide into solid carbon, kept locked in the trunks of rainforest trees for centuries.

But this massive natural “sink” for carbon cannot be relied on to continue absorbing carbon dioxide in perpetuity, a study shows. Researchers have found that, for a period in 2005, the Amazon rainforest actually slipped into reverse gear and started to emit more carbon than it absorbed.

Four years ago, a sudden and intense drought in the Amazonian dry season created the sort of conditions that give climate scientists nightmares. Instead of being a net absorber of about two billion tons of carbon dioxide, the forest became a net producer of the greenhouse gas, to the tune of about three billion tons.

The additional quantity of carbon dioxide left in the atmosphere after the drought – some five billion tons – exceeded the annual man-made emissions of Europe and Japan combined. What happened in the dry season of 2005 was a stark reminder of how quickly the factors affecting global warming can change.

“For years, the Amazon forest has been helping to slow down climate change,” said Professor Oliver Phillips, from the University of Leeds and the lead author of the study in the journal Science. “But relying on this subsidy from nature is extremely dangerous. The emission of five billion tons of carbon dioxide was huge. It meant that a major part of the biosphere had switched from one function to another, from a carbon sink to a carbon source.

“It shows what could happen if droughts become more frequent, and climate models suggest that Amazonia will get warmer and so put more water stress on vegetation. If the Earth’s carbon sinks slow or go into reverse, as our results show is possible, carbon dioxide levels will rise even faster. Deeper cuts in emissions will be required to stabilize our climate.”

The study, which involved nearly 70 scientists from 13 countries, examined more than 100,000 trees in 100 forest plots. The scientists had been monitoring changes to the girth of each tree over a period of between 20 and 30 years, so were able to calculate with some precision the effect of the 2005 drought on tree growth.

The drought itself was unusual. Normally, droughts in the Amazon are the result of changes caused by El Niño, the warm Pacific Ocean current, but the one in 2005 was a result of higher-than-average temperatures at the sea surface of the tropical North Atlantic.

“The pattern of the drought was shorter but sharper and more intense than usual,” Professor Phillips said. “It affected the southern two-thirds of Amazonia and especially the south-west through reduced rainfall and higher-than-average temperatures. It was the kind of drought we expect to see in a globally warming world. On the ground, it was hard to see because you had to detect by measuring lots of trees over a larger area of land. There was not a massive die-off of trees.”

The researchers found that the drought sharply reversed the decades-long growth of the trees. The normal die-off rate of the trees, about 1 per cent per year, doubled to 2 per cent, and the continued expansion of tree girths effectively stopped.

“Visually, most of the forest appeared little affected, but our records prove tree death rates accelerated,” Professor Phillips went on. “Because the region is so vast, even small ecological effects can scale-up to a large impact on the planet’s carbon cycle.”

Humans worldwide are estimated emit about 32 billion tons of carbon dioxide each year but just less than half of this, about 15 billion tons, remains in the atmosphere. The rest is absorbed by natural carbon sinks in the ocean and on land.

Scientists have calculated that the world’s tropical forests collectively absorb about 4.8 billion tons of carbon dioxide every year, with the Amazon being the single biggest rainforest sink. Amazonia alone is estimated to store about 100 billion tons of carbon locked up in its trees.

This is why the climate change negotiations in Copenhagen later this year will focus heavily on what can be done to save rainforests to ameliorate the effects of man-made emissions of carbon dioxide.

Lee White, the chief climate change scientist for the government of Gabon, said: “To get an idea of the value of the sink, the removal of nearly five billion tons of carbon dioxide from the atmosphere by intact tropical forests, based on realistic prices for a ton of carbon, should be valued at about £13bn a year. This is a compelling argument for conserving tropical forests.” Dr White was a co-author of another study last month on the role played by African tropical forests in processing carbon dioxide.

Professor Phillips added. “It’s surprising to see how sensitive the system appears to be. This is the first time anyone has tried to measure the impact of a big tropical drought on the ground. Now we’ve quantified it and, yes, there’s a specificity there and it wouldn’t take a huge change to shut down this thing and switch it to an overall source of carbon dioxide.”

The Amazon: Facts and figures

* The Amazon rainforest covers an area of some 600 million hectares (2.3 million sq miles), an area of land 25 times bigger than Britain. It is the biggest rainforest on Earth, responsible for about 40 per cent of the world’s rainforest absorption of carbon dioxide.

* Satellite surveys indicate that about 5,800 sq miles of the Amazon rainforest is burnt or cleared each year to make way for cattle ranching, farming or other kinds of development.

* More than half of the world’s estimated 10 million species of plants, animals and insects live in tropical rainforests. One-fifth of the world’s fresh water moves through the Amazon basin.

* Scientists estimate that there are at least 100 billion tons of carbon stored in the trees of the Amazon rainforest and each year the Amazon absorbs about 2 billion tons of carbon dioxide from the atmosphere.

* During the extreme drought of 2005, the Amazon became a net producer of carbon dioxide, releasing an estimated 3 billion tons of the greenhouse gas into the atmosphere – a net increase of 5 billion tons.

China Faces a Water Crisis

Today we go to China. A country imbued with a history of floods and droughts, China could now be facing an even greater challenge. After three decades of economic growth, hundreds of millions of its people have migrated to the cities. China is laboring under the pressure caused by a dramatic increase in demand for safe water for its citizens. Read the following article found at Business Week and written by Dexter Roberts, with Huang Zhe in Beijing to learn about China’s water crisis. Be sure to click the link at the end of the article to view the slide show.

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Source: Business Week

By Dexter Roberts, with Huang Zhe in Beijing

Over the past year getting clean water has been a struggle for many in China. In February one of the most severe droughts to hit China in a half-century affected some 5 million people and 2.5 million livestock in the provinces of Hebei and Henan, near Beijing. Farther south in Yancheng, Jiangsu, 300 kilometers from Shanghai, more than 200,000 people were cut off from clean water for three days when a chemical factory dumped carbolic acid into a river. Just before the Olympics last June, the coastal city of Qingdao, site of the sailing events, saw an explosion of algae in nearby waters that may have been caused by pollution.

These are hardly unusual in China. The country that has a long history of devastating floods and droughts arguably faces an even bigger water crisis today. After almost 30 years of double-digit economic growth and the migration of hundreds of millions of villagers to the cities, China has been barely able to meet the spike in demand for water. Its resources were scarce to begin with and pollution has made clean water even scarcer. Another unknown: the effect of climate change. “Based on our country’s basic water situation, [we] must implement the strictest water resource management,” said Vice-Premier Hui Liangyu at a national water conference in Beijing in January.

The scale of the challenge is enormous. Every year, on average 15.3 million hectares of farmland—13% of the total—faces drought. Today some 300 million people living in rural areas, or nearly a quarter of China’s population of 1.3 billion, don’t have access to safe drinking water. And among more than 600 Chinese cities, 400 are facing water shortages, including 100 that may see serious shortages, says Ma Jun, director of the Beijing-based Institute of Public & Environmental Affairs and author of China’s Water Crisis. The country would need another 40 billion cubic meters of water a year—about a tenth of the volume of Lake Erie in the U.S.—to meet the needs of all of its city dwellers fully. “China is facing a dire situation in its water supply,” says Ma.

Years of Damage

One of China’s biggest problems: wastewater. Factories and cities have discharged mostly untreated sewage and pollutants into the country’s rivers and lakes—some 53.7 billion tons in 2006 alone, according to the World Bank. China’s environmental regulators have designated 48 of China’s major lakes as seriously polluted. One-fourth of the water sampled along China’s two largest rivers—the Yangtze and Yellow—was found to be too polluted even for farm irrigation. And tap water isn’t entirely safe, either, with Chinese authorities responding to 48 large-scale environmental emergencies last year. “Extensive water pollution of course impacts on water scarcity. This is especially [true] in China,” says Washington-based Jamal Saghir, director of the Energy, Transport & Water Unit of the World Bank.

China’s huge population is a strain, too. The country’s water resources are only about 25% of the average per capita for countries around the world. That problem is compounded by a huge regional disparity. Southern China has a relative abundance of water, getting more than 2,000 millimeters (79 inches) a year of rainfall. In the north—where 17 million people live in Beijing and 12 million live in Tianjin—the average annual rainfall is just 200mm to 400mm (7.9 in. to 15.8 in.) a year. “Availability of water drops to a very low level on the north China plain, even below that of Israel,” says Ma. And this region is home to “China’s political and cultural capital, major manufacturing, and one of China’s bread baskets,” he adds.

China has worsened its own problems by offering large subsidies for water to keep prices low. That practice has led to plenty of waste, experts say.

Even though China has hiked average water prices more than tenfold in the past two decades, prices are still far below global market prices and a fraction of levels in the U.S. The global financial crisis has only made price reforms more difficult. “Water prices can be a life-or-death issue for the poor in developing countries,” says the World Bank’s Saghir. “It’s a problem because it is more difficult to implement reform when many cannot afford to pay any higher costs for water.”

Lost Opportunity

Roughly 65% of the country’s total water usage goes to agriculture, but less than half actually reaches the crops; the rest leaks from pipes, evaporates, or is otherwise lost on the way to the fields, according to World Bank statistics. And of the 25% that goes to China’s industry, the majority isn’t recycled. That compares to a recycling average of as high as 85% in developing countries. As more Chinese flock to cities, the 10% that goes to homes is likely to rise.

For now, China’s government is trying to spend its way out of the dilemma. By September of last year, the country had invested $7.46 billion into 2,712 water treatment projects, according to China’s Ministry of Environmental Protection. Beijing has embarked on a massive and controversial multibillion-dollar effort to transport water from southern regions. But the project has been delayed over both environmental concerns and resistance from the estimated 300,000 farmers who would have to be relocated because of a canal and water-pumping and cleaning facilities. High costs limit many technological solutions: Water desalination, for example, is not only expensive but requires a huge amount of energy, another resource in short supply.

At least one multinational company is taking matters into its own hands. Last October, at a conference in Beijing, Wal-Mart Stores (WMT) pledged to cut water use in half at its more than 115 China outlets over the next two years. The Bentonville (Ark.) retailer also said that starting in January 2009 it will audit all of its more than 1,000 mainland suppliers to ensure they reduce their wastewater discharges, too. The company plans to monitor emissions and hazardous waste disposal. “Sustainability in our operations and our supply chain, selling and making products in an efficient, socially, and environmentally responsible way” is Wal-Mart’s goal, former CEO and President H. Lee Scott told employees at the conference. “[It] will be essential to meeting the expectations of customers in the future,” he added.

For more on water crises globally, please see BusinessWeek.com’s slide show.

Roberts is BusinessWeek’s Asia News Editor and China bureau chief.

Australia’s Dry Run

The following article about Australia’s Darling River was found at National Geographic. The people of Australia depend on the water from the Darling for agriculture, drinking water, and tourism. As the Darling river begins to run dry, Australians find themselves facing the loss of one of their greatest sources of pride. Be sure to follow the link at the end of the article to read it in its entirety and to view the photo gallery.

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By Robert Draper
Photograph by Amy Toensing
What will happen when the climate starts to change and the rivers dry up and a whole way of life comes to an end? The people of the Murray-Darling Basin are finding out right now.

On the side of a road somewhere in southeastern Australia sits a man in a motionless pickup truck, considering the many ways in which his world has dried up. The two most obvious ways are in plain view. Just beyond his truck, his dairy cattle graze on the roadside grass. The heifers are all healthy, thank God. But there are only 70 of them. Five years ago, he had nearly 500. The heifers are feeding along a public road—”not strictly legal,” the man concedes, but what choice does he have? There is no more grass on the farm he owns. His land is now a desert scrub­land where the slightest breeze lifts a hazy wall of dust. He can no longer afford to buy grain, which is evident from the other visible reminder of his plight: the bank balance displayed on the laptop perched on the dashboard of his truck. The man, who has never been rich but also never poor, has piled up hundreds of thousands of dollars in debt. The cows he gazes at through his windshield—that is all the income he has left. continue…