July 30, 2008
Less than a month after launch, the NASA-French space agency Ocean Surface Topography Mission (OSTM)/Jason 2 oceanography 
satellite has produced its first complete maps of global ocean surface topography, surface wave height and wind speed.
The new data will help scientists monitor changes in global sea level and the distribution of heat in the ocean. This information is used to monitor climate change and ocean circulation, and to enable more accurate weather, ocean and climate forecasts. The data reveal patterns of sea level anomalies, which are used by scientists to calculate the speed and direction of ocean surface currents.
The new mission extends a 16-year continuous record of global sea level measurements begun in 1992 by the NASA/Centre National d’Etudes Spatiales (CNES) Topex/Poseidon mission and continued by the two agencies on Jason 1, launched in 2001. Data from Topex/Poseidon and Jason 1 show that mean sea level has been rising by about three millimeters (.12 inches) a year since 1993.
The new maps were generated from the first 10 days of data collected once the new satellite, OSTM/Jason 2, reached its operational orbit of 1,336 kilometers (830) miles on July 4. The new satellite and its predecessor, Jason 1, are now flying in formation in the same orbit approximately 55 seconds apart, making nearly simultaneous measurements that are allowing scientists to precisely calibrate the new satellite’s instruments. Comparisons of data from the two satellites on sea-level anomalies, significant wave height and ocean wind speed all show very close correlation of all measured parameters.
"These initial observations from OSTM/Jason 2 compare very closely to those of Jason 1," said Lee-Lueng Fu, OSTM/Jason 2 project scientist at NASA’s Jet Propulsion Laboratory, Pasadena, Calif. "To be able to collect such high-quality science data within a month of launch breaks previous records. It is also a direct reflection of how mature the field of satellite altimetry has become and of the seamless cooperation of our international team."
The satellite’s first radar altimeter data were acquired just 48 hours after its launch on June 20 from Vandenberg Air Force Base, Calif., on a Delta II rocket. The French space agency processed the first test results, followed by more advanced data results a week after launch. The more advanced results came after calculating the precise location of the satellite’s preliminary orbits. The satellite, its instruments and ground segment are all functioning properly. Once it has been fully calibrated and validated, the satellite will begin providing oceanographic products to users around the world.
OSTM/Jason 2 is an international endeavor, with responsibilities for satellite development and launch shared between NASA and CNES. CNES provided the OSTM/Jason 2 spacecraft, NASA provided the launch, and NASA and CNES jointly provided the primary payload instruments. CNES and the U.S. National Oceanic and Atmospheric Administration (NOAA) are responsible for satellite operations, while JPL is managing the mission for NASA. Data processing is being carried out by CNES, the European Organisation for the Exploitation of Meteorological Satellites (EUMETSAT) and NOAA, depending on the type of product.
Once on-orbit commissioning of OSTM/Jason 2 is completed, CNES will hand over mission operations and control to NOAA, which will then join with EUMETSAT to generate, archive and distribute data products to users worldwide.
Image Caption: OSTM/Jason 2 map of sea-level anomalies from July 4 to July 14, 2008
Image Credit: NASA / JPL
Source: NASA
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July 23, 2008
A new study has found that agricultural environments drive insects to reproduce without sex - a trait that is uncommon in most of the animal kingdom - but may provide methods for controlling their damaging effects.
Researchers at the University of Melbourne have found that when insect pests have a stable environment with abundant resources - such as grain crops, orchards, vineyards, pastures and plantations where the same crops are grown every season - they were four times more likely to reproduce without sex compared to insects overall.
“So increasing the complexity and variability of agricultural environments provides a way of potentially controlling asexual pest species” said Professor Ary Hoffmann from the Center for Environmental Stress and Adaptation Research at the University of Melbourne.
These pests include species like aphids that suck sap, mites that eat leaves, scale insect pests that feed on plant sap, beetles that eat plants and thrips that puncture plant cells.
“We looked at insects from Italy and North America, comparing databases of agricultural pest species with the insect species that can reproduce asexually - a method that is effectively cloning and so doesn’t require males and sex for reproduction”.
“We discovered that the asexual species comprised 45% (North America) or 48% (Italy) of pest species in genera where asexual reproduction occurred, compared to an overall incidence of 10% or 16% in these genera”.
“The advantage farmers have is that asexual pests will have difficulty overcoming control methods that require the evolution of changes at multiple genes, which is more easily achieved with sexual reproduction where two sets of genes combine to produce a more variable genetic make-up than just cloning,” added Dr Andrew Weeks from the department of Genetics at the University of Melbourne.
This means that asexual pests should be slower at adapting and becoming resistant to chemical controls, and should be susceptible to biological controls such as fungi that can be released like pesticides.
Asexual pests will also find it harder to adapt to new varieties of plants bred to be resistant to pests, as long as the resistance mechanisms involve several genes.
“Asexual reproduction may be favored in agricultural environments when particular clones are selected in the same stable environment across multiple generations. Asexual reproduction may also be favored as populations can be initiated by single individuals whereas sexual species require the presence of males and females”.
“Another factor is that in agricultural ecosystems, sexual reproduction cues may be absent”.
Researchers found that the high incidence of asexual reproduction in pest species is spread across different families and several insect orders.
The study was published online this week in the journal Proceedings of the Royal Society B.
Source: University of Melbourne
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July 14, 2008
University of Colorado and National Oceanic and Atmospheric Administration researchers hoping for a unique glimpse 
into the workings of the massive Greenland ice sheet are undertaking the first unmanned aerial survey of the island’s fast-flowing outlet glacier region.
This month the team is flying two small, crewless planes over a portion of the ice sheet. The goal is to understand how meltwater-fed lakes that dot the surface interact with the ice sheet’s dynamic movement and melt rate, said field campaign coordinator John Adler, a CU-Boulder doctoral student and NOAA Corps officer.
In particular, the scientists hope to learn whether the lakes can be used to predict how much water will drain from the ice sheet and contribute to sea-level rise in the future, said Adler. As the glacier moves, it forms cracks, holes and cylindrical vertical shafts in the ice known as “moulins” that allow water to rapidly drain down inside the glacier, he said.
“We want to know how much water is on top of the ice sheet, where it goes, and how much it takes to influence how fast the ice sheet slides to sea,” said Adler. Adler is studying under Professor Konrad Steffen, director of the Cooperative Institute for Research in Environmental Sciences, a joint institute of CU-Boulder and NOAA.
Researchers have been closely monitoring Greenland’s climate over the past few decades, watching to see if the ice sheet is shrinking over time, said Steffen. Greenland is currently shedding about 50 cubic miles per year, he said.
“We think these marginal melt lakes are responsible for the increase in ice velocity,” said Steffen, who maintains his own research camp on the ice sheet and also directs a network of 22 stations on the ice known as the Greenland Climate Network. “They may allow water to drain to the bottom of the ice sheet and lubricate the base.”
By using Unmanned Aircraft Systems, or UAS, the researchers will be able to fly instruments at lower altitudes than would be possible with a manned plane and survey little-explored terrain without putting human life at risk, Adler said. The two planes, known as Mantas, were provided by Advanced Ceramics Research Inc. of Tucson, Ariz. Each is less than six feet long and can fit in the bed of a pickup truck.
CIRES researcher Betsy Weatherhead, one of two lead scientists for NOAA’s UAS test bed program in the Arctic, called the Greenland effort “the start of a new era of Arctic exploration.” Weatherhead said she believes the UAS will prove to be an important tool for monitoring marine mammal populations and the thinning Arctic sea ice.
“With unmanned aircraft systems, we can fly missions too dangerous, dirty or dull for humans to address questions we couldn’t even think of addressing before,” said Weatherhead.
Each Manta will carry a digital camera, atmospheric temperature and pressure sensors, an ice-surface temperature sensor and a laser range finder to allow researchers to create high-resolution digital elevation models of Greenland’s Jakobshavn glacial region, said Steffen. The planes will fly between 500 and 1,000 feet above the surface at speeds of about 45 miles per hour for up to six hours.
Each plane will carry a special camera that will collect information from across the electromagnetic spectrum to probe the depth of lakes on top of the ice sheet, said Adler. By measuring the amount of sunlight penetrating the lake water, researchers can estimate lake depth and the potential amounts of water that could drain through the ice sheet and out to sea, he said.
Image Caption: Greenland ice sheet
Image Credit: Hannes Grobe, Alfred Wegener Institute for Polar and Marine Research
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July 12, 2008
Olympic National Park was created in 1938, in part “to preserve the finest sample of primeval forests in the entire 
United States” – but a new study at Oregon State University suggests that this preservation goal has failed, as a result of the elimination of wolves and subsequent domination of the temperate rainforests by herds of browsing elk.
The park, with streamside ecosystems that have been largely denuded of the young trees needed to replace the old ones, and stream systems that bear little resemblance to the narrower and vegetation-lined rivers of the past, is now anything but “primeval” and a very different place than it was 70 years ago, researchers say.
The extermination of wolves in the early 1900s set off a “trophic cascade” of changes that appear to have affected forest vegetation and stream dynamics, with possible impacts on everything from fisheries to birds and insects, the scientists wrote in their report, just published in the journal Ecohydrology.
Members of the Press Expedition, hiking in 1890 through what is now Olympic National Park, found the banks of the upper Quinault River “so dense with underbrush as to be almost impenetrable,” they wrote at the time. Logs jammed the rivers, dense tree canopies shaded and cooled the streams, and trout and salmon thrived along with hundreds of species of plants and animals.
“Today, you go through the same area and instead of dense vegetation that you have to fight through, it’s a park-like stand of predominantly big trees,” said Bill Ripple, a co-author of the study and forestry professor at Oregon State University. “It’s just a different world.”
That world may still be quite beautiful with its jagged, glacier-covered peaks and towering old-growth trees. But it’s not the same one that so impressed President Theodore Roosevelt in 1909 that he created Mount Olympus National Monument – in large part to help protect elk herds that had been decimated by hunting. The Roosevelt elk, a massive animal that now bears his name, can weigh more than 1,000 pounds.
With protection from hunters and extermination of wolves not long after that, elk populations surged, and OSU researchers say that in the intervening decades the very nature of Olympic National Park has changed dramatically.
“Our study shows that there has been almost no recruitment of new cottonwood and bigleaf maple trees since the wolves disappeared, and also likely impacts on streamside shrubs, which are very important for river stability,” said Robert Beschta, lead author of the study and professor emeritus of forest hydrology at OSU. “Decreases in woody plant communities allow river banks to rapidly erode and river channels to widen.”
“Tree and shrub species along stream banks and floodplains started crashing first,” Beschta said. “Then, apparently, the rivers began to unravel. Now we have large areas where the forest understory vegetation is mostly just grasses and ferns.”
The study showed that river dynamics are quite different than they were historically. Streams that once were held together in tight channels by heavy bank vegetation are now wider and braided, with exposed gravel bars a common feature. The water is open to the warming sun and less enriched by plants and insects. Nearly half of the terraces along the Queets River have disappeared because of accelerated erosion over a period of multiple decades.
“We’ve seen the impact of wolves on the ecosystem in Yellowstone, the effect of cougars in Yosemite National Park, the same basic story about the importance of key predators being played out in many different places,” Ripple said. “What’s so surprising here is that it’s happening in a temperate rainforest, which is hugely productive and has such high levels of vegetation growth. But even there, when the ecosystem gets overwhelmed with many large herbivores, the vegetation just can’t keep up.”
In an area outside Olympic National Park where little foraging by elk occurred, tree recruitment has been normal and healthy in recent decades.
Since the Olympic National Park ecosystem bears some similarity to much of the temperate rainforests in the Coast Range of Oregon, Washington and British Columbia – with a mild climate and heavy levels of rainfall – it’s reasonable to believe similar forces are at work elsewhere when historic predators have been removed, the scientists said.
“Unlike some of the studies we’ve done in the Rocky Mountains, arid desert or canyon ecosystems, for us this one is hitting a little closer to home,” said Beschta, a forest hydrologist who has studied Pacific Northwest streams for more than 30 years. “These processes are at work right in our backyard.”
In multiple studies in the U.S. and Canada, usually in national parks where supposedly “pristine” ecosystems are still available, the OSU scientists in recent years have documented the critical impacts on ecosystems when key predators disappear – usually wolves or cougars. It has been shown that such predators help control the grazing impacts of elk and deer on several levels, by keeping their population levels down, but also in changing their patterns of behavior – a process that has been called “the ecology of fear.”
In the most classic case where these predators have been brought back into the ecosystem – wolves in Yellowstone National Park – OSU scientists have found that some stream ecosystems are now starting to recover where they had been in serious decline for more than half a century. Streamside trees and shrubs, beaver dams, and native plants, animals and fisheries are being restored.
An effort was considered to restore wolves to the Olympic National Park ecosystem in recent years, but no decision or actions have been undertaken to accomplish that, the OSU scientists said.
Source: Oregon State University
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July 11, 2008
About one third of the world’s species of coral are facing extinction, according to a major new global study.
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July 10, 2008
Environmental groups sued the U.S. Forest Service in federal court today arguing that the agency has concealed impacts of old-growth logging to the environment and to subsistence hunting in four Tongass National Forest timber projects. At issue is whether environmental impact statements have thoroughly evaluated the effect of the projects on Sitka black-tailed deer – a species that is key to viability of the “Islands Wolf” (Alexander Archipelago wolf) and is among the most important subsistence foods in the area.
The plaintiffs are Greenpeace and Cascadia Wildlands Project, both of which have offices in Alaska. They say the Forest Service has violated bedrock environmental laws by deliberately ignoring their legitimate criticisms of how impacts to deer were assessed in the decision process and not providing a “full and fair discussion” of their concerns. While not a plaintiff in the suit, the Alaska Department of Fish & Game has repeatedly challenged these same flaws.
“The Forest Service has misapplied the science and has stonewalled all challenges,” said Greenpeace forest campaigner Larry Edwards. “We have sought resolution for years. Now the courts are the only recourse.”
The lawsuit demands that the four logging projects be stopped and that supplemental analysis be ordered to fairly evaluate their impacts. Combined, the projects would take 33 million board feet of timber from 1,700 acres of old-growth forest and construct 9.5 miles of new, permanent logging roads.
“Ancient forest logging reduces the ability of the forest to sustain deer in winter,” said Gabe Scott, Alaska field representative for Cascadia Wildlands Project in Cordova. “When old-growth forests are logged, deer become more vulnerable to population collapses during hard winters, and the Tongass has had recent record-setting snowfalls consistent with climate change factors for the region. Deer are a vital food source both for residents of the region and the Islands Wolf.”
The Tongass, America’s largest national forest, has been a flashpoint of controversy for decades. It is the world’s largest remaining temperate rainforest that is still relatively intact. Even so, viability of Tongass wildlife species – the Islands Wolf prominent among them – is a well acknowledged concern. In 1997, the Forest Service avoided a ‘threatened’ listing of the Islands Wolf under the Endangered Species Act by including a protective standard in its then new Tongass Forest Plan. The standard was intended to protect both the wolf’s “viability and wide distribution” and the needs of families that depend on deer for food on the table.
“The rule the Forest Service was forced to adopt is in the way of its ambition to expand the Tongass timber program,” Edwards said. “We think it is no accident that the agency’s deer habitat modeling errors all work in one direction – consistently overestimating habitat by as much as 120 percent and consequently underestimating logging impacts.”
Chris Winter of the Crag Law Center is representing the plaintiffs in the case.
Source: Greenpeace USA
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July 8, 2008
Argentina’s Perito Moreno Glacier has begun a rare winter rupture. Officials say there is no prior record of such an ice break during the southern hemisphere’s winter months of June through August
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July 8, 2008
President Bush and other world leaders made gradual progress Tuesday on climate change, but finalizing a long-term global agreement on what to do about the fevered planet remains elusive.
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July 8, 2008
A new government survey says almost half the coral reef ecosystems in U.S. territory are in poor or fair condition, mostly because of rising ocean temperatures.
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July 4, 2008
It’s not just about climate change anymore. Besides loading the atmosphere with heat-trapping greenhouse gases, human emissions of carbon dioxide have also begun to alter the chemistry of the ocean—often called the cradle of life on Earth. The ecological and economic consequences are difficult to predict but possibly calamitous, warn a team of chemical oceanographers in the July 4 issue of Science, and halting the changes already underway will likely require even steeper cuts in carbon emissions than those currently proposed to curb climate change.
Ken Caldeira of the Carnegie Institution’s Department of Global Ecology, writing with lead author Richard Zeebe of the University of Hawaii and two co-authors*, note that the oceans have absorbed about 40% of the carbon dioxide (CO2) emitted by humans over the past two centuries. This has slowed global warming, but at a serious cost: the extra carbon dioxide has caused the ocean’s average surface pH (a measure of water’s acidity) to shift by about 0.1 unit from pre-industrial levels. Depending on the rate and magnitude of future emissions, the ocean’s pH could drop by as much as 0.35 units by the mid-21st century.
This acidification can damage marine organisms. Experiments have shown that changes of as little as 0.2-0.3 units can hamper the ability of key marine organisms such as corals and some plankton to calcify their skeletons, which are built from pH-sensitive carbonate minerals. Large areas of the ocean are in danger of exceeding these levels of pH change by mid-century, including reef habitats such as Australia’s Great Barrier Reef.
Most marine organisms live in the ocean’s sunlit surface waters, which are also the waters most vulnerable to CO2-induced acidification over the next century as emissions continue. To prevent the pH of surface waters from declining more than 0.2 units, the current limit set by the U.S. Environmental Protection Agency in 1976, carbon dioxide emissions would have to be reduced immediately.
“In contrast to climate model predictions, such future ocean chemistry projections are largely model-independent on a time scale of a few centuries,” the authors write, “mainly because the chemistry of CO2 in seawater is well known and changes in surface ocean carbonate chemistry closely track changes in atmospheric CO2.”
Although the ocean’s chemical response to higher carbon dioxide levels is relatively predictable, the biological response is more uncertain. The ocean’s pH and carbonate chemistry has been remarkably stable for millions of years—much more stable than temperature.
“We know that ocean acidification will damage corals and other organisms, but there’s just no experimental data on how most species might be affected,” says Caldeira. “Most experiments have been done in the lab with just a few individuals. While the results are alarming, it’s nearly impossible to predict how this unprecedented acidification will affect entire ecosystems.” Reduced calcification will surely hurt shellfish such as oysters and mussels, with big effects on commercial fisheries. Other organisms may flourish in the new conditions, but this may include undesirable “weedy” species or disease organisms.
Though most of the scientific and public focus has been on the climate impacts of human carbon emissions, ocean acidification is as imminent and potentially severe a crisis, the authors argue.
“We need to consider ocean chemistry effects, and not just the climate effects, of CO2 emissions. That means we need to work much harder to decrease CO2 emissions,” says Caldeira. “While a doubling of atmospheric CO2 may seem a realistic target for climate goals, such a level may mean the end of coral reefs and other valuable marine resources.”
* James Zachos, University of California, Santa Cruz, and Toby Tyrrell, Southampton University, U.K
Source: Carnegie Institution of Washington
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satellite has produced its first complete maps of global ocean surface topography, surface wave height and wind speed. 
