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WASHINGTON, Nov. 24 (Xinhua) -- A new study suggests that the rate of global warming from doubling of atmospheric carbon dioxide may be less than the most dire estimates of some previous studies.Authors of the study, which was funded by the National Science Foundation and published online on Thursday in the journal Science, say that global warming is real and that increases in atmospheric CO2 will have multiple serious impacts. However, the most Draconian projections of temperature increases from the doubling of CO2 are unlikely."Many previous climate sensitivity studies have looked at the past only from 1850 through today, and not fully integrated paleoclimate date, especially on a global scale," said Andreas Schmittner, an Oregon State University researcher and lead author on the Science article. "When you reconstruct sea and land surface temperatures from the peak of the last Ice Age 21,000 years ago -- which is referred to as the Last Glacial Maximum -- and compare it with climate model simulations of that period, you get a much different picture.""If these paleoclimatic constraints apply to the future, as predicted by our model, the results imply less probability of extreme climatic change than previously thought," Schmittner added.Scientists have struggled for years trying to quantify "climate sensitivity" -- which is how the Earth will respond to projected increases of atmospheric carbon dioxide. The 2007 IPCC report estimated that the air near the surface of the Earth would warm on average by two to 4.5 degrees (Celsius) with a doubling of atmospheric CO2 from preindustrial standards. The mean, or " expected value" increase in the IPCC estimates was 3.0 degrees; most climate model studies use the doubling of CO2 as a basic index.The researchers based their study on ice age land and ocean surface temperature obtained by examining ices cores, bore holes, seafloor sediments and other factors. When they first looked at the paleoclimatic data, the researchers only found very small differences in ocean temperatures then compared to now."Our study implies that we still have time to prevent that from happening, if we make a concerted effort to change course soon," said Schmittner.

YICHANG, Oct. 30 (Xinhua) -- China's Three Gorges Dam on Sunday reached its designed highest mark, the second time for the world's largest water control and hydropower project to run at full capacity.The water level hit 175 meters at 5 p.m. after storing water for nearly two months from the water level of 152 meters, said an official with the China Three Gorges Project Corporation (CTGPC), the developer of the project.A dozen hydropower turbo-generator units started operation on Sunday, generating power capacity of 8.2 million kw, said the official.The dam in central China's Hubei Province completed its first full-capacity test last October.Operating at full capacity should give full play to the dam's functions of generating hydroelectric power, delivering water to the lower reaches to alleviate spring droughts, and containing water from summer flooding, as required by the State Flood Control and Drought Relief Headquarters.The Three Gorges Project was launched in 1993 with a budget equivalent to 22.5 billion U.S. dollars.So far, monitoring shows the dam is operating smoothly.

WASHINGTON, Nov. 10 (Xinhua) -- Using its near-infrared vision to peer nine billion years back in time, NASA's Hubble Space Telescope has uncovered an extraordinary population of young dwarf galaxies brimming with star formation, the U.S. space agency announced on Thursday.While dwarf galaxies represent the most common type of galaxy in the universe, the rapid star-birth observed in these newly- found examples may force astronomers to reassess their understanding of the ways in which galaxies form.The galaxies are a hundred times less massive, on average, than the Milky Way, yet they churn out stars at such a furious pace that their stellar content would double in just 10 million years. By comparison, the Milky Way would take a thousand times longer to double its star population.The universe is estimated to be 13.7 billion years old, and these newly-discovered galaxies are extreme even for the young universe -- when most galaxies were forming stars at higher rates than they are today. Astronomers using Hubble's instruments could spot the galaxies because the radiation from young, hot stars has caused the oxygen in the gas surrounding them to light up like a bright neon sign."The galaxies have been there all along, but up until recently astronomers have been able only to survey tiny patches of sky at the sensitivities necessary to detect them," said Arjen van der Wel of the Max Planck Institute for Astronomy in Germany, lead author of a paper on the results to be published online on Nov. 14 in The Astrophysical Journal. "We weren't looking specifically for these galaxies, but they stood out because of their unusual colors. "The observations were part of the Cosmic Assembly Near-infrared Deep Extragalactic Legacy Survey (CANDELS), an ambitious three- year study to analyze the most distant galaxies in the universe. CANDELS is the first census of dwarf galaxies at such an early epoch."In addition to the images, Hubble has captured spectra that show us the oxygen in a handful of galaxies and confirmed their extreme star-forming nature," said co-author Amber Straughn at NASA's Goddard Space Flight Center. "Spectra are like fingerprints. They tell us the galaxies' chemical composition."The CANDELS team uncovered the 69 young dwarf galaxies in near- infrared images taken with Hubble's Wide Field Camera 3 and Advanced Camera for Surveys.The observations suggest that the newly-discovered galaxies were very common nine billion years ago. However, it is a mystery why the newly-found dwarf galaxies were making batches of stars at such a high rate.

WASHINGTON, Nov. 21 (Xinhua) -- The launch of the Mars Science Laboratory, which contains the car-sized Curiosity rover, has been delayed by a day to Nov. 26, the U.S. National Aeronautics and Space Administration (NASA) announced Monday.The delay will "allow time for the team to remove and replace a flight termination system battery," NASA said in a statement.The launch is now scheduled for 10:02 a.m. (1502 GMT) on Saturday from Cape Canaveral Air Force Station, Florida. The launch window remains open for one hour and 43 minutes.Curiosity is about twice as long and more than five times as heavy as any previous Mars rover. Its 10 science instruments include two for ingesting and analyzing samples of powdered rock delivered by the rover's robotic arm.Scheduled to land on the Mars in August 2012, the one-ton rover will examine Gale Crater during a nearly two-year prime mission. Curiosity will land near the base of a layered mountain three miles (five kilometers) high inside the crater. The rover will investigate whether environmental conditions ever have been favorable for development of microbial life and preserved evidence of those conditions.

WASHINGTON, Nov. 9 (Xinhua) -- An international team of researchers funded by NASA and the National Science Foundation (NSF) will travel next month to one of Antarctica's most active, remote and harsh spots to determine how changes in the waters circulating under an active ice sheet are causing a glacier to accelerate and drain into the sea, the U.S. space agency announced Wednesday.The science expedition will be the most extensive ever deployed to Pine Island Glacier. It is the area of the ice-covered continent that concerns scientists most because of its potential to cause a rapid rise in sea level. Satellite measurements have shown this area is losing ice and surrounding glaciers are thinning, raising the possibility the ice could flow rapidly out to sea.The multidisciplinary group of 13 scientists, led by Robert Bindschadler, emeritus glaciologist of NASA's Goddard Space Flight Center, will depart from the McMurdo Station in Antarctica in mid- December and spend six weeks on the ice shelf. During their stay, they will use a combination of traditional tools and sophisticated new oceanographic instruments to measure the shape of the cavity underneath the ice shelf and determine how streams of warm ocean water enter it, move toward the very bottom of the glacier and melt its underbelly."The project aims to determine the underlying causes behind why Pine Island Glacier has begun to flow more rapidly and discharge more ice into the ocean," said Scott Borg, director of NSF's Division of Antarctic Sciences, the group that coordinates all U.S. research in Antarctica. "This could have a significant impact on global sea-level rise over the coming century."

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