Scientific American Topic - Global Warming

American Pika Denied Endangered Species Status

Fri, 05 Feb 2010 14:30:00 EST

The Fish and Wildlife Service has rejected a bid to extend endangered species protection to a rabbit-like creature that environmentalists say could be pushed to extinction by rising temperatures.

The warming of the American pika's mountain habitat in California's Sierra Nevada and in parts of nine other Western states has shrunk the tiny mammal's population and could eliminate part of its range, but federal biologists say new studies suggest the pika will adjust to warmer homes or migrate to cooler areas upslope.

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Wolverine No Match for Climate Change

Thu, 04 Feb 2010 17:00:08 EST

Forget polar bears or penguins. The charismatic megafauna suffering most from climate change may well be the wolverine--a vicious predator known for its uncanny strength and tenacity. Making it the perfect inspiration for the X-Me n superhero.

The actual wolverine's super powers extend mostly to a tolerance for Arctic chill and supersized feet to permit quicker movement on snow. Those big feet might be hurting the largest member of the weasel family as snowpack declines across much of North America.

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The Bigger Kahuna: Are More Frequent and Higher Extreme Ocean Waves a By-Product of Global Warming?

Tue, 02 Feb 2010 17:30:00 EST

Armand Thibault looked out over the Pacific's rumbling winter waves from his balcony in Neskowin, Ore. "The predicted high tide today is a 10.1 [feet]," he relayed via YouTube on Friday, January 29. "I'm very glad we don't have a storm surge behind this one. Tomorrow is supposed to be a 10.2, so it should be interesting." [More]

U.S. Commits to Greenhouse Gas Cuts under Copenhagen Climate Accord

Fri, 29 Jan 2010 19:01:00 EST

The U.S. officially committed in writing yesterday to the greenhouse gas emission cuts proposed by President Obama in Copenhagen --4 percent below 1990 levels by 2020. The letter to the United Nations Framework Convention on Climate Change (UNFCCC) commits the nation to combat climate change, but with a caveat: any such commitment must be backed by legislation, which has not passed the U.S. Senate. [More]

Is Water Vapor in the Stratosphere Slowing Global Warming?

Fri, 29 Jan 2010 10:00:00 EST

Earth's stratosphere is a cold, dry place, above the troposphere--the bottom layer of the atmosphere we breathe on a daily basis. Ruled by winds and hosting everything from bacteria to long-distance jet travel, about the only way that water gets into this high-altitude layer 10 kilometers above the Earth's surface is when it billows up from the humid tropics, rising from the troposphere via the atmospheric interface known as the tropopause. But since 2001 there has been less water vapor in a narrow, lower band of the stratosphere thanks to cooler temperatures in the tropopause, and that may just be holding back global warming at ground level, according to new research published online in Science on January 28. [More]

Fixing the Global Nitrogen Problem (preview)

Wed, 27 Jan 2010 08:00:00 EST

Billions of people today owe their lives to a single discovery now a century old. In 1909 German chemist Fritz Haber of the University of Karlsruhe figured out a way to transform nitrogen gas--which is abundant in the atmosphere but nonreactive and thus unavailable to most living organisms--into ammonia, the active ingredient in synthetic fertilizer. The world’s ability to grow food exploded 20 years later, when fellow German scientist Carl Bosch developed a scheme for implementing Haber’s idea on an industrial scale.

Over the ensuing decades new factories transformed ton after ton of industrial ammonia into fertilizer, and today the Haber-Bosch invention commands wide respect as one of the most significant boons to public health in human history. As a pillar of the green revolution, synthetic fertilizer enabled farmers to transform infertile lands into fertile fields and to grow crop after crop in the same soil without waiting for nutrients to regenerate naturally. As a result, global population skyrocketed from 1.6 billion to six billion in the 20th century.

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Scrutinizing Swamp Gas: Model Helps Predict Global Wetland Greenhouse Emissions

Fri, 22 Jan 2010 11:00:00 EST

Methane ranks only behind water vapor and carbon dioxide among principal greenhouse gases , in terms of its abundance and global warming potential. Even though it is less abundant and has a shorter lifetime in the atmosphere than carbon dioxide, methane in the atmosphere accounts for nearly 20 percent of the heating effect of greenhouse gases compared with carbon dioxide's 50 percent. And similar to CO2, methane in the atmosphere emanates from both anthropogenic and natural sources. [More]

How Fast Are Himalayan Glaciers Melting?

Thu, 21 Jan 2010 07:00:08 EST

The village of Brep in Pakistan doesn't exist in the same place anymore. That's because a torrential flood forced the community to move after a lake formed by glacial meltwater burst its bounds and leveled the town.

Glacial lake outbursts have become a yearly occurrence across the high mountain region stretching from Afghanistan to Bhutan sometimes called the Roof of the World.

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Making Good Time: Doomsday Clock Moves 1 Minute Back to 6 from Midnight

Thu, 14 Jan 2010 17:45:00 EST

The human race can breathe a tiny bit easier (but not too much) now that the Bulletin of the Atomic Scientists has moved the hand of its Doomsday Clock one minute farther away from midnight, the time which symbolizes catastrophic destruction and the apocalyptic end of civilization. The clock now reads six minutes from that end-of-days witching hour after it was changed during a press conference Thursday in New York City, citing an increased awareness and interest in stopping key threats to humanity (in particular nuclear conflict and global warming) since U.S. President Barack Obama took office about a year ago. [More]

Copenhagen Accord Was an "Important Step Forward," Says U.S. Climate Negotiator

Thu, 14 Jan 2010 16:30:00 EST

Lead U.S. climate negotiator Todd Stern said Thursday the Copenhagen Accord represents the best way forward for a binding global climate deal but that success likely rests with a smaller group of major emitters working outside the unwieldy, multi-national United Nations process. [More]

What Would Failure to Combat Climate Change Quickly Mean?

Tue, 12 Jan 2010 16:15:00 EST

BOULDER, Colo. – Turns out climate policy has some tipping points. [More]

In the 12 Months of 2009

Thu, 31 Dec 2009 11:56:08 EST

In the first month of 2009 people gave to me: a coal ash spill in Tennessee. (Technically occurred in 2008, but it lingered.) [More]

Combating climate change by observing Earth

Wed, 30 Dec 2009 11:41:00 EST

As part of the U.S. charm offensive at the recent Copenhagen summit on climate change , a roughly one meter-diameter orb helped display a decade's worth of climate data collected by NASA satellites. "This is the golden age," NASA's Jack Kaye told me. As associate research director for the agency's Earth Science Division, he's "reaping the benefits of the 1990s."

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South Asian Threat? Local Nuclear War = Global Suffering (preview)

Wed, 30 Dec 2009 08:00:00 EST

Twenty-five years ago international teams of scientists showed that a nuclear war between the U.S. and the Soviet Union could produce a “nuclear winter.” The smoke from vast fires started by bombs dropped on cities and industrial areas would envelop the planet and absorb so much sunlight that the earth’s surface would get cold, dark and dry, killing plants worldwide and eliminating our food supply. Surface temperatures would reach winter values in the summer. International discussion about this prediction, fueled largely by astronomer Carl Sagan, forced the leaders of the two superpowers to confront the possibility that their arms race endangered not just themselves but the entire human race. Countries large and small demanded disarmament.

Nuclear winter became an important factor in ending the nuclear arms race. Looking back later, in 2000, former Soviet Union leader Mikhail S. Gorbachev observed, “Models made by Russian and American scientists showed that a nuclear war would result in a nuclear winter that would be extremely destructive to all life on earth; the knowledge of that was a great stimulus to us, to people of honor and morality, to act.”

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Climate Numerology: How Much Atmospheric Carbon Dioxide Is Safe?

Tue, 29 Dec 2009 08:00:00 EST

Last December world leaders met in Copenhagen to add more hot air to the climate debate. That is because although the impacts humanity would like to avoid--fire, flood and drought, for starters--are pretty clear, the right strategy to halt global warming is not. Despite decades of effort, scientists do not know what “number”--in terms of temperature or concentrations of greenhouse gases in the atmosphere--constitutes a danger.

When it comes to defining the climate’s sensitivity to forcings such as rising atmospheric carbon dioxide levels, “we don’t know much more than we did in 1975,” says climatologist Stephen Schneider of Stanford University, who first defined the term “climate sensitivity” in the 1970s. “What we know is if you add watts per square meter to the system, it’s going to warm up.”

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Velocity of Climate Change Varies from Mountain to Marsh

Wed, 23 Dec 2009 16:45:00 EST

Reports of maples on the march northward and butterflies flitting far afield are already flooding in, and climate scientists predict that with escalating temperature changes more species will need to either get out of dodge, or hope for emissions reductions that will help the planet dodge the climate bullet. [More]

Accord of Sorts in Copenhagen

Sat, 19 Dec 2009 10:18:08 EST

An accord, of sorts, in Copenhagen. UNESCO’s Christina Reed:

“So it got really tense, [Danish prime minister Lars Loekke] Rasmussen had the gavel in the air and said, ‘It looks like we don’t have a consensus, I hate to do this but,’ and as he was about to pound, the U.K.’s Ed Miliband, negotiator, said, ‘I call for an adjournment,’ and so they adjourned, and everyone broke and they adjourned. This short adjournment lasted about two hours, they met off the floor to discuss this a little bit more in person. It was face-to-face arm wringing, it was ‘let’s get this done, let’s move this ahead.’ Ultimately it was Ban Ki-moon of the United Nations working very diligently.”

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U.S., China, India and Other Nations Arrive at Nonbinding Agreement at U.N. Climate Summit

Fri, 18 Dec 2009 20:00:00 EST

Editor's note: After this story was posted, delegates at the U.N. Climate Summit resumed negotiations into the early hours of Saturday morning and the body eventually came to a consensus to recognize the deal outlined in the story below.

COPENHAGEN--The U.S., China, India and South Africa form the core of a growing group of nations that have agreed upon a commitment to combat climate change , concluding a grueling two weeks of negotiations in the Danish capital here as part of the United Nations' climate summit. The so-called "Copenhagen Accord" will not be legally binding but will list in annexed documents, for the first time, commitments from both developed and developing countries to reduce emissions of greenhouse gases . [More]

Copenhagen's Carbon Debt

Fri, 18 Dec 2009 11:04:08 EST

[Crowd Noise] That's the sound of climate change negotiations--and CO2 being released. All this talking is a seemingly significant source of greenhouse gas emissions and not just because negotiators have traveled to Copenhagen from all corners of the globe. [More]

With One Space Observatory Down, NASA Uses Another to Map CO2

Thu, 17 Dec 2009 18:45:00 EST

SAN FRANCISCO--The Orbiting Carbon Observatory, or OCO , was designed to monitor the movement of carbon dioxide in Earth's atmosphere starting this year, but instead it plunged into the ocean in February due to a launch malfunction. Now an instrument on another NASA probe is enabling researchers to map atmospheric CO2, and revealing that its global distribution is surprisingly uneven, with regional variations of up to 5 percent. [More]