Asia pollution may boost U.S. temperatures

• Story Highlights
• Report says air pollution in Asia may raise summer temperatures in the U.S.
  
• Authors: Shorter-term pollutants cause more localized warming than once thought
  
• "What they do about their pollution can affect our climate," scientist says
  
• Pollution likely to create "hot spots" in the world, one in the central United States
  

GTON (AP) -- Smog, soot and other particles like the kind often seen hanging over Beijing add to global warming and may raise summer temperatures in the American heartland by three degrees in about 50 years, says a new federal science report released Thursday.

Smog like this seen over Beijing, China, is caused mostly from burning wood and from driving trucks and cars.

These overlooked, shorter-term pollutants -- mostly from burning wood and kerosene and from driving trucks and cars -- cause more localized warming than once thought, the authors of the report say.

They contend there should be a greater effort to attack this type of pollution for faster results.

For decades, scientists have concentrated on carbon dioxide, the most damaging greenhouse gas because it lingers in the atmosphere for decades. Past studies have barely paid attention to global warming pollution that stays in the air merely for days.

The new report, written by scientists with NASA and the National Oceanic and Atmospheric Administration, makes a case for tackling the short-term pollutants, while acknowledging that carbon dioxide is still the chief cause of warming.

That concept is also the official policy of the Bush Administration, said assistant secretary of commerce Bill Brennan.

In the United States, this approach would mean cutting car and truck emissions perhaps before restricting coal-burning power plants. In the developing world, especially Asia, it would mean shifting to cleaner energy sources, more like those used in the Western world. Much of this type of pollution in Asia comes from burning kerosene and biofuels, such as wood and animal dung.

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In addition to soot, smog and sulfates, other short-lived pollutants are organic carbon, dust and nitrates. While carbon dioxide is invisible, these are pollutants people can see.

Projected increases in some of these pollutants and decreases in others in Asia will eventually add up to about 20 percent of the already-predicted man-made summer warming in America by 2060, the report said.

"What they do about their pollution can affect our climate," said study co-author Hiram "Chip" Levy, a senior scientist at NOAA's fluid dynamics lab in Princeton, New Jersey.

This pollution will likely create three "hot spots" in the world: the central United States, Europe around the Mediterranean Sea, and Kazakhstan, which borders Russia and China. In the United States it's "a big blob in the middle of the country" stretching from the Rocky Mountains to the Appalachians, Levy said.

The same analysis also shows about an inch less of yearly rain in middle America because of Asian emissions by about 2060.

As far as American-produced pollution, smog is the main problem. Reducing diesel emissions and increasing mass transit would prove a more effective and immediate strategy over limiting power plants, said study co-author Drew Shindell, a climate scientist at NASA's Goddard Institute for Space Studies in New York.

The report makes sense, but should also include a strategy for man-made methane, a greenhouse gas which lasts 10 years in the atmosphere, said Michael MacCracken, chief scientist at the Climate Institute in Washington.

Methane mostly comes from landfills, natural gas use, livestock, coal mining and sewage treatment, according to the U.S. Environmental Protection Agency

As ocean surface temperatures rise, so do hurricanes' strength

David Perlman, Chronicle Science Editor

(09-03) 19:14 PDT -- Hurricanes have grown more and more powerful over the past 30 years as ocean surface temperatures - probably aided by global warming - have increased, climate scientists said today.

The trend is worldwide, the researcher said, but the evidence is strongest in the North Atlantic, which takes in the Caribbean and the Gulf of Mexico, where just days ago hurricane Gustav bore down on the Louisiana coast, reviving memories of Katrina.

"The fact that Gustav reached category 4 in the increasingly warm Caribbean is consistent with what we've noted as a trend over the past 30 years," James B. Elsner, leader of a hurricane research team at Florida State University said Wednesday in an e-mail.

The one-two punch of Gustav and of Katrina, the category 5 hurricane that devastated New Orleans just three years ago, he said, "might be a harbinger of things to come in a warmer world as the observed and modeled consequence of climate change."

The study is appearing today in the journal Nature just a day after two other published reports concluded that for the past decade temperatures throughout the Northern Hemisphere have been warmer than at any time in the past 1,300 years.

Surface temperatures both on land and sea have been rising for centuries, and when ocean surfaces heat up they provide energy that can whip the circular winds of normal storms over the ocean into full-scale hurricanes.

Using satellite measurements, Elsner and researchers at the University of Wisconsin studied the peak wind speeds of storms over the world's tropic oceans that later grew to become full-scale hurricanes.

The result, they said, was consistent with the long-held hypothesis that "as the seas warm, the ocean has more energy to convert to tropical winds." More often now than in the past, those winds have speeded up to become hurricanes, Elsner's team has found.

The link between those hurricanes and sea surface temperatures during the past three decades was most clear in the North Atlantic, but it was less significant in other parts of the world, the scientists concluded.

In an earlier review of the links between climate change and hurricane intensity, published in the journal Geophysical Research Letters, Elsner noted that his results "have serious implications for life and property throughout the Caribbean, Mexico and portions of the United States."

The Elsner report follows reports by Peter Webster, Judith Curry and their colleagues at George Tech University who, after studying the increasing intensity of hurricanes and their links to rising sea surface temperatures, concluded in a report published in Science that hurricane intensities worldwide have more than doubled since 1970.

Hurricane intensity is measured on what is called the Saffir-Simpson scale. The weakest are Category 1, in which winds reach from 74 to 95 mph, and the strongest are Category 4, with sustained winds from 131 to 155 mph, and Category 5, such as Katrina, with winds of 156 mph or more.

In the 35 years before 2004, the number of the weakest Category 1 hurricanes that reached Category 4 or 5 rose worldwide from 17 percent to 35 percent, they reported. In an e-mail Wednesday, Curry said that today some 41 percent of all Category 1 hurricanes have increased to Category 4 or 5 in the past five years.

"This increase is associated with the trend of increasing sea surface temperatures associated with global warming, although the link with sea surface temperature is more complex than originally thought," Curry said.

Referring to Hurricane Gustav, Curry cautioned that "you can't attribute the intensity of any single storm to global warming."

E-mail David Perlman at dperlman@sfchronicle.com.

Major ice-shelf loss for Canada

Ward Hunt is the largest of the remnant ice shelves

The ice shelves in Canada's High Arctic have lost a colossal area this year, scientists report.

The floating tongues of ice attached to Ellesmere Island, which have lasted for thousands of years, have seen almost a quarter of their cover break away.

One of them, the 50 sq km (20 sq miles) Markham shelf, has completely broken off to become floating sea-ice.

Researchers say warm air temperatures and reduced sea-ice conditions in the region have assisted the break-up.

"These substantial calving events underscore the rapidity of changes taking place in the Arctic," said Trent University's Dr Derek Mueller.

"These changes are irreversible under the present climate."

Satellite images show the loss of the Markham Ice Shelf over the last year

Scientists reported in July that substantial slabs of ice had calved from Ward Hunt Ice Shelf, the largest of the Ellesmere shelves.

Similar changes have been seen in the other four shelves.

As well as the complete breakaway of the Markham, the Serson shelf lost two sections totalling an estimated 122 sq km (47 sq miles), and the break-up of the Ward Hunt has continued.

Cold remnants

The shelves themselves are merely remnants of a much larger feature that was once bounded to Ellesmere Island and covered almost 10,000 sq km (3,500 sq miles).

Over the past 100 years, this expanse of ice has retreated by 90%, and at the start of this summer season covered just under 1,000 sq km (400 sq miles).

Much of the area was lost during a warm period in the 1930s and 1940s.

"Long meltwater lakes" were imaged on the Markham shelf in 2005

Temperatures in the Arctic are now even higher than they were then, and a period of renewed ice shelf break-up has ensued since 2002.

Unlike much of the floating sea-ice which comes and goes, the shelves contain ice that is up to 4,500 years old.

A rapid sea-ice retreat is being experienced across the Arctic again this year, affecting both the ice attached to the coast and floating in the open ocean.

The floating sea-ice, which would normally keep the shelves hemmed in, has shrunk to just under five million sq km, the second lowest extent recorded since the era of satellite measurement began about 30 years ago.

"Reduced sea-ice conditions and unusually high air temperatures have facilitated the ice shelf losses this summer," said Dr Luke Copland from the University of Ottawa.

"And extensive new cracks across remaining parts of the Ward Hunt Ice Shelf mean that it will continue to disintegrate in the coming years."

Loss of ice in the Arctic, and in particular the extensive sea-ice, has global implications. The "white parasol" at the top of the planet reflects energy from the Sun straight back out into space, helping to cool the Earth.

Further loss of Arctic ice will see radiation absorbed by darker seawater and snow-free land, potentially warming the Earth's climate at an even faster rate than current observational data indicates.

Coal plans go up in smoke

Environmentalists in the US have halted a huge new wave of coal-fired power stations. What lessons can Europe learn from them?

• Juliette Jowit
• The Guardian,
• Wednesday September 3 2008
• Article history

One day, historians might speculate that it was the ambition of the companies that sought to profit by building coal-fired power stations that triggered the beginning of the end for humans' most polluting habit.

Four years ago, campaigners in the US raised concerns over plans to build 150 coal-fired power stations nationwide. Today, nearly half those plans have been defeated in the courts or abandoned, while half of the remaining proposals are being actively opposed. Just 14 of the 150 plants are being developed, and environmental lawyers are all still pursuing them.

"The enormity of what they were proposing to do provided a platform to have that whole debate about pollution, including global-warming pollution, " says Bruce Nilles , director of the national coal campaign for the Sierra Club, America's biggest grassroots environment group.

Firmer action

In a few years, the backlash against coal power in America has become the country's biggest-ever environmental campaign, transforming the nation's awareness of climate change and inspiring political leaders to take firmer action after years of doubt and delay. Plants have been defeated in at least 30 of the 50 states, uniting those with already strong environmental records, such as California, with more conservative areas, such as the southern and central states.

The success of the US campaign is also now inspiring a global wave of protests, many in Europe, against similar schemes that plan to build coal-fired generators before carbon capture technology exists. If the European protesters succeed, Nilles believes US legislators will be likely to support presidential candidates' promises to join international efforts to cut emissions. By implication, though, if the protesters fail in Europe, the impact on a US or international deal would be disastrous.

The US anti-coal campaign is being linked to protests against similar plans in Australia, Germany, Italy and the UK, where there are demonstrations at almost every public appearance by E.ON, the company that plans to build Britain's first new first new coal power station for two decades in Kingsnorth, Kent, where protesters set up a protest camp against the new development in August.

US campaigners say they are concerned that if the UK and other European countries go ahead with new coal plants, the momentum to tackle climate change will be lost. " The rest of the world has been leading on this, particularly Europe," says Nilles. "Building new coal makes it increasingly difficult, if not impossible, to meet [emissions] targets, so it's critical the European community countries do not fail."

Coal power returned to the US political agenda when vice-president Dick Cheney's 2001 energy policy lifted key pollution restrictions. It took two years for environmental groups to see what emerged: state by state, project by project, a total of 150 new plants were put forward, almost all of them not to replace old coal but to augment it. Individually, some plants would have emitted more CO2 than some African countries. Together, the plants would have emitted an estimated1bn tonnes of CO2 annually - more than the total emissions cuts by countries that have signed the Kyoto protocol.

That realisation mobilised an incredible national campaign, led by a few national groups including the Sierra Club, the Union of Concerned Scientists and others, but driven by state and local membership of these and many more organisations and employing a wide array of tactics. The first job was to raise public awareness that the cumulative threat was far greater than each local project, says Nilles. "The projects were moving through the public process and nobody was paying any attention."

Using town hall debates, local media and political connections, they stirred up interest and recruited new supporters to the cause, including powerful hunting and fishing interests and religious leaders in the Appalachian mountain states, where opencast coal mining is often affecting the poorest communities. Then the campaign began. State politicians were persuaded to legislate either against emissions, as in the case of California, or in favour of alternatives such as renewables and energy efficiency, in Minnesota. Campaigners targeted banks, telling them that investing in coal might be too risky because of the threat of international emissions caps and high carbon prices, prompting the banks to set tougher conditions on lending.

Then the environmentalists highlighted a little-noticed Federal grant fund that gave billions of dollars for new coal power; following their publicity six planned plants were dropped. Legal challenges successfully blocked more plants on the basis of local pollution in Illinois and Montana. It was also proven that burning coal was not the cheapest method of generating electricity, breaking state rules in Minnesota and Florida.

In 2007 the US Supreme Court ruled that greenhouse gases were a pollutant under the clean air act and so could be regulated. In July this year for the first time a coal plant in Georgia was blocked by a local court using this ruling. Meanwhile, concrete and steel prices have escalated so high that other projects have been dropped on cost grounds.

Extreme weather

It is not only energy policy that has changed: public opinion on climate change has been transformed during this time, thanks in part to extreme weather events across the US, says Nilles.

"The sceptics will say that you can't say one flood is down to global warming. That's right, but we can see an up-tick in extreme and unprecedented weather patterns: wildfires sweeping across California, the drought that stretches [across] the southern tier of states, extreme flooding up in the mid-west, and an up-tick in tornados across the Great Plains."

Public opinion, in turn, has helped persuade at least six states, directly or through emissions limits, to put an effective moratorium on new coal power - California, Washington, Oregon and, perhaps more surprisingly, the conservative southern and midwest states of Florida, Idaho and Kansas. Governors of states that have taken action are also now putting pressure on their peers to stop them building generators that would wipe out their own hard-won emissions reductions. Nilles believes new coal power is now doomed in the US. "My sense is less than 10% [of the 150 plants proposed] will ultimately get built," he says. After this campaign, protesters will turn their attention to existing coal power and the mining industry, he says. "Ultimately, we need to phase out coal entirely .We don't need it and it's very expensive. The US has some of the best [renewable energy] resources in the world."

Growing resistance

In Germany, where 25 plants have been mooted, campaigners are winning local referendums and blocking the proposals. India has also had some resistance to new coal, for example in Chamalapura near the city of Mysore. China is facing a fierce public response to pollution caused by coal and other industrial sites: an environmental official in 2006 estimated there had been 51,000 pollution-related protests the previous year. In Australia, protesters kicked off six planned climate camps around the world this year by chaining themselves to a coal train and blocking access to two plants.
Source: European Climate Foundation