Monday, December 7, 2009  

Earth More Sensitive to Carbon Dioxide Than Previously Thought

ScienceDaily (Dec. 7, 2009) — In the long term, the Earth’s temperature may be 30-50% more sensitive to atmospheric carbon dioxide than has previously been estimated, reports a new study published in Nature Geoscience.

The results show that components of the Earth’s climate system that vary over long timescales — such as land-ice and vegetation — have an important effect on this temperature sensitivity, but these factors are often neglected in current climate models.

Dan Lunt, from the University of Bristol, and colleagues compared results from a global climate model to temperature reconstructions of the Earth’s environment three million years ago when global temperatures and carbon dioxide concentrations were relatively high. The temperature reconstructions were derived using data from three million-year-old sediments on the ocean floor.

Lunt said, “We found that, given the concentrations of carbon dioxide prevailing three million years ago, the model originally predicted a significantly smaller temperature increase than that indicated by the reconstructions. This led us to review what was missing from the model.”

The authors demonstrate that the increased temperatures indicated by the reconstructions can be explained if factors that vary over long timescales, such as land-ice and vegetation, are included in the model. This is primarily because changes in vegetation and ice lead to more sunlight being absorbed, which in turn increases warming.

Including these long-term processes in the model resulted in an increased temperature response of the Earth to carbon dioxide, indicating that the Earth’s temperature is more sensitive to carbon dioxide than previously recognised. Climate models used by bodies such as the Intergovernmental Panel on Climate Change often do not fully include these long-term processes, thus these models do not entirely represent the sensitivity of the Earth’s temperature to carbon dioxide.

Alan Haywood, a co-author on the study from the University of Leeds, said “If we want to avoid dangerous climate change, this high sensitivity of the Earth to carbon dioxide should be taken into account when defining targets for the long-term stabilisation of atmospheric greenhouse-gas concentrations.”

Lunt added: “This study has shown that studying past climates can provide important insights into how the Earth might change in the future.”

(a) shows predicted global temperatures when processes that adjust on relatively short-term timescales (for example sea-ice, clouds, and water vapour) are included in the model

(b) includes additional long-tem processes that adjust on relatively long timescales (vegetation and land-ice).

This research was funded by the Research Council UK and the British Antarctic Survey.

www.sciencedaily.com December 07, 2009.

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Friday, November 13, 2009  

Can Alternative Energy Save the Economy and the Climate?

BRIGHTON, Colo. – The low-carbon economy has already arrived on the windy prairie north of this fast-growing Denver ‘burb. It’s here that Danish wind-turbine giant Vestas converted 298 acres of hayfield into the West’s largest turbine factory – and turned Brighton into a magnet for “green” energy companies.

It’s part of a $1 billion investment by the company in the United States, what Colorado Gov. Bill Ritter touts as a “new energy economy.”

“We have a caseload of 56 prospects. Of those, a majority are energy-related industries,” said Raymond Gonzales, president of the Brighton Economic Development Corporation. “People are looking. They’re not slowing down. And they’re aggressively looking at the United States.”

Some say these efforts – not the upcoming Copenhagen climate treaty talks – provide the most promising route to energy independence, climate change mitigation and job creation.

Regardless of whether delegates emerge next month with a comprehensive replacement for the Kyoto Protocol, industry’s full-throttle acceleration toward a low-carbon future will continue, they say.

Vestas isn’t the only company spending millions of its capital. Several utilities are investing some $1 billion on an industrial-scale carbon capture and storage tests at coal plants in Wisconsin, West Virginia and Oklahoma. The race to perfect the batteries that will power the next generation of automobiles and buses has manufacturers in Europe, the United States and China scurrying to build plants and research centers.

“The vast majority of the utility industry (has) pretty much accepted the reality that CO2 is something they have to cope with,” said Revis James, director of the energy technology assessment center for the Electric Power Research Institute, or EPRI, a California-based nonprofit that helps drive long-range development and is coordinating carbon capture experiments at coal plants in the Midwest and Southeast.

Failure in Copenhagen won’t “substantially stop what’s going to happen,” James added. “The utilities have to deal with (carbon emissions). They have to respond one way or another.”

Many business leaders and policy analysts counter the status quo – a piecemeal, federated approach to carbon and energy emissions – doesn’t carry enough of a signal to produce the revolution required of our economic and energy sectors.

Private-sector investments and regional and local government efforts to boost “green” technology are good, they say. But that’s just the down payment: The transformative change necessary to avoid the worst warming won’t come until the international community firmly sets a global standard in place.

“What you want is something sustainable, predictable and long-term,” said Roby Roberts, spokesman for Vestas Americas. “That’s what you want out of the climate rules, but that’s going to be a few years away.”

Article Continued at http://www.scientificamerican.com/article.cfm?id=copenhagen-consequences-investments-low-carbon

Scientific American, November 13, 2009.

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