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.

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.

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).

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.