October 30, 2010

Is the ice at the South Pole melting?

The change in the ice mass covering Antarctica is a critical factor in global climate events. Scientists at the GFZ German Research Centre for Geosciences have now found that the year by year mass variations in the western Antarctic are mainly attributable to fluctuations in precipitation, which are controlled significantly by the climate phenomenon El Nino. They examined the GFZ data of the German-American satellite mission GRACE (Gravity Recovery and Climate Experiment). The investigation showed significant regional differences in the western coastal area of the South Pole area.

October 28, 2010

Scientists issue call to action for archaeological sites threatened by rising seas

Should global warming cause sea levels to rise as predicted in coming decades, thousands of archaeological sites in coastal areas around the world will be lost to erosion. With no hope of saving all of these sites, archaeologists Torben Rick from the Smithsonian Institution, Leslie Reeder of Southern Methodist University, and Jon Erlandson of the University of Oregon have issued a call to action for scientists to assess the sites most at risk.
Writing in the Journal of Coastal Conservation and using California's Santa Barbara Channel as a case study, the researchers illustrate how quantifiable factors such as historical rates of shoreline change, wave action, coastal slope and shoreline geomorphology can be used to develop a scientifically sound way of measuring the vulnerability of individual archaeological sites. They then propose developing an index of the sites most at risk so informed decisions can be made about how to preserve or salvage them.

October 19, 2010

Drought may threaten much of globe within decades

The United States and many other heavily populated countries face a growing threat of severe and prolonged drought in coming decades, according to results of a new study by National Center for Atmospheric Research (NCAR) scientist Aiguo Dai.
The detailed analysis concludes that warming temperatures associated with climate change will likely create increasingly dry conditions across much of the globe in the next 30 years.
The drought may reach a scale in some regions by the end of the century that has rarely, if ever, been observed in modern times.
Using an ensemble of 22 computer climate models and a comprehensive index of drought conditions, as well as analyses of previously published studies, the paper reports that by the 2030s, dryness is likely to increase substantially across most of the Western Hemisphere, along with large parts of Eurasia, Africa, and Australia.
By later this century, many of the world's most densely populated regions will be threatened with severe drought conditions.

Air pollution exposure increases risk of severe COPD

Long term exposure to low-level air pollution may increase the risk of severe chronic obstructive pulmonary disease (COPD), according to researcher s in Denmark. While acute exposure of several days to high level air pollution was known to be a risk factor for exacerbation in pre-existing COPD, until now there had been no studies linking long-term air pollution exposure to the development or progression of the disease.
The research was published online ahead of the print edition of the American Thoracic Society's American Journal of Respiratory and Critical Care Medicine.
"Our findings have significance on a number of levels," said lead researcher on the study, Zorana Andersen, Ph.D., post doctoral fellow at the Institute of Cancer Epidemiology of the Danish Cancer Society in Copenhagen. "Patients, primary care physicians, pulmonologists and public health officials should all take not of our findings."

Climate Change May Alter Natural Climate Cycles of Pacific

While it’s still hotly debated among scientists whether climate change causes a shift from the traditional form of El Nino to one known as El Nino Modoki, online in the journal Nature Geoscience, scientists now say that El Nino Modoki affects long-term changes in currents in the North Pacific Ocean.
El Nino is a periodic warming in the eastern tropical Pacific that occurs along the coast of South America. Recently, scientists have noticed that El Nino warming is stronger in the Central Pacific rather than the Eastern Pacific, a phenomenon known as El Nino Modoki (Modoki is a Japanese term for "similar, but different").
Last year, the journal Nature published a paper that found climate change is behind this shift from El Nino to El Nino Modoki. While the findings of that paper are still being debated, this latest paper in Nature Geoscience presents evidence that El Nino Modoki drives a climate pattern known as the North Pacific Gyre Oscillation (NPGO).

October 16, 2010

Carbon dioxide controls Earth's temperature

Water vapor and clouds are the major contributors to Earth's greenhouse effect, but a new atmosphere-ocean climate modeling study shows that the planet's temperature ultimately depends on the atmospheric level of carbon dioxide.
The study, conducted by Andrew Lacis and colleagues at NASA's Goddard Institute for Space Studies (GISS) in New York, examined the nature of Earth's greenhouse effect and clarified the role that greenhouse gases and clouds play in absorbing outgoing infrared radiation. Notably, the team identified non-condensing greenhouse gases -- such as carbon dioxide, methane, nitrous oxide, ozone, and chlorofluorocarbons -- as providing the core support for the terrestrial greenhouse effect.
Without non-condensing greenhouse gases, water vapor and clouds would be unable to provide the feedback mechanisms that amplify the greenhouse effect. The study's results will be published Friday, Oct. 15 in Science.

Charcoal biofilter cleans up fertilizer waste gases

Removing the toxic and odorous emissions of ammonia from the industrial production of fertilizer is a costly and energy-intensive process. Now, researchers in Bangladesh have turned to microbes and inexpensive wood charcoal to create a biofilter that can extract the noxious gas from vented gases and so reduce pollution levels from factories in the developing world.
Writing in the International Journal of Environment and Pollution, Jahir Bin Alam, A. Hasan and A.H. Pathan of the Department of Civil and Environmental Engineering, at Shahjalal University of Science and Technology, in Sylhet, explain that biofiltration using soil or compost has been used to treate waste gases for the last two decades. There are simple filters for reducing odors and more sophisticated units for removing specific chemicals, such as hydrogen sulfide, from industrial sources.

Carbon dioxide controls Earth's temperature

Water vapor and clouds are the major contributors to Earth's greenhouse effect, but a new atmosphere-ocean climate modeling study shows that the planet's temperature ultimately depends on the atmospheric level of carbon dioxide.
The study, conducted by Andrew Lacis and colleagues at NASA's Goddard Institute for Space Studies (GISS) in New York, examined the nature of Earth's greenhouse effect and clarified the role that greenhouse gases and clouds play in absorbing outgoing infrared radiation. Notably, the team identified non-condensing greenhouse gases -- such as carbon dioxide, methane, nitrous oxide, ozone, and chlorofluorocarbons -- as providing the core support for the terrestrial greenhouse effect.
Without non-condensing greenhouse gases, water vapor and clouds would be unable to provide the feedback mechanisms that amplify the greenhouse effect. The study's results will be published Friday, Oct. 15 in Science.

October 14, 2010

New research results change the understanding of atmospheric aerosol properties and climate effects

Atmospheric fine particles affect the Earth's radiation balance by interacting with solar radiation and by participating in cloud formation. Biogenic volatile organic compounds are key players in new particle formation processes. Hence, terrestrial vegetation has an important role as the newly formed particles cool our climate. The chemical composition of such secondary organic aerosol (SOA) particles formed from volatile compounds emitted by vegetation is very complicated and only limited information on the phase state of SOA particles has been available. Thus the scientific community has tried to understand the chemical composition and physical characteristics of SOA particles in order to better understand their climatic implications and also to enable more accurate predictions using global climate models.

Can Hungary's red sludge be made less toxic with carbon?

The red, metal-laden sludge that escaped a containment pond in Hungary last week could be made less toxic with the help of carbon sequestration, says an Indiana University Bloomington geologist who has a patent pending on the technique.
The bauxite residue now covers 40 square kilometers south of the Danube River, and has caused the deaths of eight Hungarians and injured at least 150. The residue also has caused the extinction of life in a local river and as yet unknown environmental damage elsewhere. While human deaths in the wake of the disaster may have been strictly a result of the containment failure, injuries have mostly been attributed to the chemical properties of the sludge, whose high pH (between 11 and 13) can quickly damage and kill living cells. Bauxite residue is between 10,000 and 1,000,000 times more basic than pure water, which has a pH around 7.
"We propose one way to reduce the pH of bauxite residue is to mix it with another kind of industrial waste -- oil-field brine, which is a by-product of oil and gas production -- and then carbon dioxide," said IU Bloomington geologist Chen Zhu, who submitted a U.S. Department of Energy patent application in 2007 describing the technique.

October 9, 2010

Measurements of CO2 and CO in China's air indicate sharply improved combustion efficiency

A collaborative, six-year study of carbon dioxide (CO2) levels in Beijing and surrounding provinces suggests that combustion efficiency, a component of overall energy efficiency, is improving in the region.
The findings, published in the September 21 issue of Atmospheric Chemistry and Physics, are generally consistent with official Chinese government statistics and could bolster their credibility as international negotiations proceed on commitments of China and other nations to combat climate change.
A team of atmospheric scientists and environmental engineers from Harvard University and Tsinghua University in Beijing have continuously measured atmospheric CO2 and carbon monoxide (CO) levels in rural Miyun, about 100 km northeast of Beijing, since November 2004.
Weather observations such as wind speed and direction (with other evidence) allowed researchers to identify plumes of polluted air from the Beijing urban area and population centers to the south, as opposed to relatively clean air arriving from the north.

October 6, 2010

Switching off your lights has a bigger impact than you might think, says new study

The power stations that supply electricity vary in their carbon dioxide emission rates, depending on the fuel they use: those that burn fossil fuels (coal, gas and oil) have higher emissions than those driven by nuclear power and wind. In general only the fossil fuel power stations are able to respond instantly to changes in electricity demand.
Dr Adam Hawkes, the author of the new study from the Grantham Institute for Climate Change at Imperial College London, says the government should keep track of changing carbon emission rates from power stations to ensure that policy decisions for reducing emissions are based on robust scientific evidence. The new study suggests that excluding power stations with low carbon emission rates, such as wind and nuclear power stations, and focussing on those that deal with fluctuating demand would give a more accurate emission figure.

Study sheds new light on how the sun affects the Earth's climate

The Sun's activity has recently affected the Earth's atmosphere and climate in unexpected ways, according to a new study published today in the journal Nature. The study, by researchers from Imperial College London and the University of Colorado, shows that a decline in the Sun's activity does not always mean that the Earth becomes cooler.
It is well established that the Sun's activity waxes and wanes over an 11-year cycle and that as its activity wanes, the overall amount of radiation reaching the Earth decreases. Today's study looked at the Sun's activity over the period 2004-2007, when it was in a declining part of its 11-year activity cycle.
Although the Sun's activity declined over this period, the new research shows that it may have actually caused the Earth to become warmer. Contrary to expectations, the amount of energy reaching the Earth at visible wavelengths increased rather than decreased as the Sun's activity declined, causing this warming effect.

October 5, 2010

Climate change affects horseshoe crab numbers

Having survived for more than 400 million years, the horseshoe crab is now under threat – primarily due to overharvest and habitat destruction. However, climatic changes may also play a role. Researchers from the University of Gothenburg reveal how sensitive horseshoe crab populations are to natural climate change in a study recently published in the scientific journal Molecular Ecology.
The horseshoe crab is often regarded as a living fossil, in that it has survived almost unchanged in terms of body design and lifestyle for more than 400 million years. Crabs similar to today's horseshoe crabs were walking the Earth long before the dinosaurs.

October 3, 2010

A painless way to achieve huge energy savings: Stop wasting food

Scientists have identified a way that the United States could immediately save the energy equivalent of about 350 million barrels of oil a year — without spending a penny or putting a ding in the quality of life: Just stop wasting food. Their study, reported in ACS' semi-monthly journal Environmental Science & Technology, found that it takes the equivalent of about 1.4 billion barrels of oil to produce, package, prepare, preserve and distribute a year's worth of food in the United States.
Michael Webber and Amanda Cuéllar note that food contains energy and requires energy to produce, process, and transport. Estimates indicate that between 8 and 16 percent of energy consumption in the United States went toward food production in 2007. Despite this large energy investment, the U.S. Department of Agriculture estimates that people in the U.S. waste about 27 percent of their food. The scientists realized that the waste might represent a largely unrecognized opportunity to conserve energy and help control global warming.

October 1, 2010

Genetically Altered Trees and Plants Could Help Counter Global Warming

Forests of genetically altered trees and other plants could sequester several billion tons of carbon from the atmosphere each year and so help ameliorate global warming, according to estimates published in the October issue of BioScience.
The study, by researchers at Lawrence Berkeley National Laboratory and Oak Ridge National Laboratory, outlines a variety of strategies for augmenting the processes that plants use to sequester carbon dioxide from the air and convert it into long-lived forms of carbon, first in vegetation and ultimately in soil. Besides increasing the efficiency of plants' absorption of light, researchers might be able to genetically alter plants so they send more carbon into their roots—where some may be converted into soil carbon and remain out of circulation for centuries.
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