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New research finds mangroves key to climate change

2011-04-05T16:33:00.003+05:30

New research shows that mangroves store exceptionally more carbon than most tropical forests, but they are being destroyed from coastlines at a rapid rate causing significant emissions of greenhouse gases.

The findings from the study, which was carried out by scientists from the Center for International Forestry Research (CIFOR) and the USDA Forest Service, underscore a call by scientists for mangroves to be protected as part of global efforts to combat climate change.

"Mangroves are being destroyed at an alarming rate. This needs to stop. Our research shows that mangroves play a key role in climate change mitigation strategies," said Daniel Murdiyarso, Senior Scientist at CIFOR, a co-author of the paper, entitled Mangroves among the most carbon-rich forests in the topics.

In the study, which was published on April 3 in Nature GeoScience, scientists quantified carbon storage in mangroves across a large tract of the Indo-pacific region. No studies to date have integrated the necessary measurements for total mangrove carbon storage across broad geographic domains.

From the results, the scientists estimated that the destruction and degradation of mangrove forests may be generating as much as 10% of all the global deforestation emissions despite accounting for just 0.7% of tropical forest area. Much of that carbon is stored in the ground below the mangroves forests that can be seen above the ground and water.

Deforestation and land-use change currently account for 8% to 20% of all global carbon emissions, second only to the use of fossil fuels. An international initiative known as REDD+ (reduced emissions from deforestation and forest degradation) is considered one of the most cost-effective ways to slow the rate of climate change.

Mangroves occur along the coasts of most major oceans in some 118 countries. A 30% to 50% decline in mangroves over the past half-century has raised fears that they may disappear altogether in as little as 100 years.

Rapid 21st century sea level rise has also been cited as a primary threat to mangroves, which have responded to past more gradual sea-level changes by migrating landward or upward. Under current climate trends, sea level is projected to rise 18-79 centimeters this century - and even higher if ice-sheet melting continues accelerating.

Mangroves are also being threatened by increasing pressures from urban and industrial developments, as well as fish farms.

"There is a lack of awareness of the full implications of mangrove loss for humankind," Murdiyarso said. "There is an urgent need for governments to acknowledge their importance and develop better policies to ensure their protection."

Mangroves are not only key to climate change mitigation efforts, they also play important roles in adapting to the changing climate. They protect coastlines from storm surges and fluctuations in sea levels, including from tsunamis.

Volcanoes have shifted Asian rainfall

2010-11-09T10:44:00.001+05:30

Scientists have long known that large volcanic explosions can affect the weather by spewing particles that block solar energy and cool the air. Some suspect that extended "volcanic winters" from gigantic blowups helped kill off dinosaurs and Neanderthals. In the summer following Indonesia's 1815 Tambora eruption, frost wrecked crops as far off as New England, and the 1991 blowout of the Philippines' Mount Pinatubo lowered average global temperatures by 0.7 degrees F — enough to mask the effects of man-made greenhouse gases for a year or so.

Now, scientists have shown that eruptions also affect rainfall over the Asian monsoon region, where seasonal storms water crops for nearly half of earth's population. Tree-ring researchers at Columbia University's Lamont-Doherty Earth Observatory showed that big eruptions tend to dry up much of central Asia, but bring more rain to southeast Asian countries including Vietnam, Laos, Cambodia, Thailand and Myanmar — the opposite of what many climate models predict. Their paper appears in an advance online version of the journal Geophysical Research Letters.

The growth rings of some tree species can be correlated with rainfall, and the observatory's Tree Ring Lab used rings from some 300 sites across Asia to measure the effects of 54 eruptions going back about 800 years. The data came from Lamont's new 1,000-year tree-ring atlas of Asian weather, which has already produced evidence of long, devastating droughts; the researchers also have done a prior study of volcanic cooling in the tropics. "We might think of the study of the solid earth and the atmosphere as two different things, but really everything in the system is interconnected," said Kevin Anchukaitis, the study's lead author. "Volcanoes can be important players in climate over time."

Large explosive eruptions send up sulfur compounds that turn into tiny sulfate particles high into the atmosphere, where they deflect solar radiation. Resulting cooling on earth's surface can last for months or years. (Not all eruptions will do it; for instance, the continuing eruption of Indonesia's Merapi this fall has killed dozens, but this latest episode is probably not big enough by itself to effect large-scale weather changes.) As for rainfall, in the simplest models, lowered temperatures decrease evaporation of water from the surface into the air; and less water vapor translates to less rain. But matters are greatly complicated by atmospheric circulation patterns, cyclic changes in temperatures over the oceans, and the shapes of land masses. Up to now, most climate models incorporating known forces such as changes in the sun and atmosphere have predicted that volcanic explosions would disrupt the monsoon by bringing less rain to southeast Asia--but the researchers found the opposite.

The researchers studied eruptions including one in 1258 from an unknown tropical site, thought to be the largest of the last millennium; the 1600-1601 eruption of Peru's Huaynaputina; Tambora in 1815; the 1883 explosion of Indonesia's Krakatau; Mexico's El Chichón, in 1982; and Pinatubo. The tree rings showed that huge swaths of southern China, Mongolia and surrounding areas consistently dried up in the year or two following big events, while mainland southeast Asia got increased rain. The researchers say there are many possible factors involved, and it would speculative at this point to say exactly why it works this way.

"The data only recently became available to test the models," said Rosanne D'Arrigo, one of the study's coauthors. "Now, it's obvious there's a lot of work to be done to understand how all these different forces interact." For instance, in some episodes pinpointed by the study, it appears that strong cycles of the El Niño-Southern Oscillation, which drives temperatures over the Pacific and Indian oceans and is thought to strongly affect the Asian monsoon, might have counteracted eruptions, lessening their drying or moistening effects. But it could work the other way, too, said Anchukaitis; if atmospheric dynamics and volcanic eruptions come together with the right timing, they could reinforce one another, with drastic results. "Then you get flooding or drought, and neither flooding nor drought is good for the people living in those regions," he said. The study also raises questions whether proposed "geo-engineering" schemes to counteract man-made climate change with huge artificial releases of volcanism-like particles might have complex unintended consequences.

Ultimately, said Anchukaitis, such studies should help scientists refine models of how natural and man-made forces might act together to in the future to shift weather patterns — a vital question for all areas of the world.

Climate Change May Create Tipping Points for Populations, Not Just Species

2010-10-25T18:04:00.000+05:30

A single moss campion plant shows the influence of climate change on entire populations.
Credit: Tracy Feldman Researchers measure survival, reproduction of thousands of arctic and alpine plants over six years

As Earth's climate warms, species are expected to shift their geographical ranges away from the equator or to higher elevations.

While scientists have documented such shifts for many plants and animals, the ranges of others seem stable.

When species respond in different ways to the same amount of warming, it becomes more difficult for ecologists to predict future biological effects of climate change--and to plan for these effects.

In a study published this week in the journal Nature, University of Wyoming ecologist Daniel Doak and Duke University ecologist William Morris report on a long-term study of arctic and alpine plants.

The results show why some species may be slow to shift their geographic ranges in the face of climate change, and why we might expect to see sudden shifts as warming continues.

"This study illustrates the critical need for long-term research to address our most pressing ecological challenges," says Saran Twombly, program director in the National Science Foundation (NSF)'s Division of Environmental Biology, which funded the research.

"Without the temporal and spatial scales employed here, we have little hope of understanding the complex ways in which organisms will respond to climate change."

The plant species targeted by Morris and Doak range from populations in the high mountains of Colorado and New Mexico to species growing along the arctic coastline in far northern Alaska.

These regions include habitats that have undergone substantial climate change, leading to the expectation, says Doak, that--especially at the southern edge of their range--populations of the plants should be collapsing.

However, after studying the growth and survival of tens of thousands of individual plants over six years, the researchers show a more complex pattern of responses.

At the southern edge of their ranges, the plants indeed show negative effects of warmer conditions, with lower survival.

"But in most years," says Doak, "these effects are balanced by plants in the south growing more rapidly, so that populations there are no less stable than those in the north."

The opposing trends mean that under current conditions, even across the huge range of conditions Morris and Doak studied, populations of these plants are doing equally well across 30 degrees of latitude--one-third the distance from the equator to the north pole.

However, the researchers' results don't indicate that these plants, or other species, will be unaffected by warming conditions.

By looking at the performance of individual plants in particularly hot and cold years, they found that the compensatory effects across moderately cold to moderately warm years (lower survival balanced by more rapid growth) will not hold up with increased warming.

Instead, in the warmest years at all study sites, both survival and growth of the plants fell.

"Up to a point," says Doak, "we may see little effect of warming for many organisms. But past a climatic tipping point, the balance of opposing effects of warming will likely cease, leading to subsequent rapid declines in populations."

While this tipping point will be different for each species, responses of natural populations to gradual shifts in climate will not necessarily in turn be gradual.

"We shouldn't interpret a lack of ecological response to past warming to mean that little or no effects are likely in the future," says Doak.

The researchers' work also points to a methodology with which to better understand and predict how climate effects on one species will combine to create overall population-wide effects.

"A key part of this approach is the need for long-term studies so we can observe and use the rare years with extreme climates to anticipate what the average future climate will bring," Doak says.

Climate threatens trout and salmon

2010-05-23T17:38:00.000+05:30

Trout and salmon are among the world's most familiar freshwater fishes, but numbers have fallen over recent decades – in some areas, dramatically. Pollution, habitat loss and over-fishing have all been blamed in the past, but new evidence from Cardiff University shows that climate change could be a major factor, putting both species at risk.

The scientists studied populations of young salmon and trout in the River Wye in Wales, traditionally one of the UK's best angling rivers. Professor Steve Ormerod and colleagues from the Cardiff School of Biosciences found salmon numbers fell by 50% and trout numbers by 67% between 1985 and 2004 - even though the river itself became cleaner.

The fish were hit hardest following hot, dry summers such as 1990, 2000 and 2003. The results suggest that warmer water and lower river levels combine to affect both species. As both trout and salmon favour cool water, they face potentially major problems if climate warming continues as expected in the next two to three decades.

"Huge efforts have been put into bringing salmon back into Europe's formerly polluted rivers such as the Taff, Thames, Clyde, Seine and Rhine, so these results are a major worry," said Professor Ormerod.

"Salmon and trout fishing also generate many jobs and large economic benefits. In Wales alone, salmon fishing contributes around £90 million annually. Any risk of eventually losing these species to climate warming is therefore one we must consider very seriously. We suggest measures to ensure that river levels are maintained in hotter conditions alongside the use of riverside trees to create shade and protect against the highest temperatures. This week's Wales Sustainability Week is an ideal opportunity for us to consider action for Welsh rivers, particularly because trout and salmon are such important sustainability indicators."

The Cardiff team used data on fish population collected each year by the Environment Agency at more than 50 locations spread throughout the Wye. Stream temperatures increased over the study period by 0.5 – 0.7ºC in summer and 0.7 - 1.0ºC in winter, with the latter effects apparently affecting the fish at low flow. Water temperature is known to affect growth and susceptibility to disease in these fish, while lower water levels restrict their access to cooler habitats.

Peter Gough, fisheries scientist with Environment Agency Wales, added,
"We recognise that climate warming is probably already affecting many elements of our natural environment, including salmon, trout and sea trout, and this detailed analysis of our long-term data is extremely interesting and, if proven correct, would be of great concern. We are currently examining these and other data further.

There is a suggestion that earlier migration to sea of salmon smolts might account for at least part of the apparent decline, but this doesn't explain the reduction in trout numbers. More work is needed to clarify some important issues."
The comparison between trout and salmon is important because, unlike salmon, trout from the Wye never migrate to the sea. Only factors affecting the river can therefore explain their decline.

A paper on the findings has been published in one of the world's leading environmental journals, Global Change Biology.

Did phosphorus trigger complex evolution – and blue skies?

2010-05-11T19:36:00.000+05:30

The evolution of complex life forms may have gotten a jump start billions of years ago, when geologic events operating over millions of years caused large quantities of phosphorus to wash into the oceans. According to this model, proposed in a new paper by Dominic Papineau of the Carnegie Institution for Science, the higher levels of phosphorus would have caused vast algal blooms, pumping extra oxygen into the environment which allowed larger, more complex types of organisms to thrive.

"Phosphate rocks formed only sporadically during geologic history," says Papineau, a researcher at Carnegie's Geophysical Laboratory, "and it is striking that their occurrences coincided with major global biogeochemical changes as well as significant leaps in biological evolution."

In his study, published in the journal Astrobiology, Papineau focused on the phosphate deposits that formed during an interval of geologic time known as the Proterozoic, from 2.5 billion years ago to about 540 million years ago. "This time period is very critical in the history of the Earth, because there are several independent lines of evidence that show that oxygen really increased during its beginning and end," says Papineau. The previous atmosphere was possibly methane-rich, which would have given the sky an orangish color. "So this is the time that the sky literally began to become blue."

During the Proterozoic, oxygen levels in the atmosphere rose in two phases: first ranging from 2.5 to 2 billion years ago, called the Great Oxidation Event, when atmospheric oxygen rose from trace amounts to about 10% of the present-day value. Single-celled organisms grew larger during this time and acquired cell structures called mitochondria, the so-called "powerhouses" of cells, which burn oxygen to yield energy. The second phase of oxygen rise occurred between about 1 billion and 540 million years ago and brought oxygen levels to near present levels. This time intervals is marked by the earliest fossils of multi-celled organisms and climaxed with the spectacular increase of fossil diversity known as the "Cambrian Explosion."

Papineau found that these phases of atmospheric change corresponded with abundant phosphate deposits, as well as evidence for continental rifting and extensive glacial deposits. He notes that both rifting and climate changes would have changed patterns of erosion and chemical weathering of the land surface, which would have caused more phosphorous to wash into the oceans. Over geologic timescales the effect on marine life, he says, would have been analogous to that of high-phosphorus fertilizers washed into bodies of water today, such as the Chesapeake Bay, where massive algal blooms have had a widespread impact.

"Today, this is happening very fast and is caused by us," he says, "and the glut of organic matter actually consumes oxygen. But during the Proterozoic this occurred over timescales of hundreds of millions of years and progressively led to an oxygenated atmosphere."

"This increased oxygen no doubt had major consequences for the evolution of complex life. It can be expected that modern changes will also strongly perturb evolution," he adds. "However, new lineages of complex life-forms take millions to tens of millions of years to adapt. In the meantime, we may be facing significant extinctions from the quick changes we are causing."

Soil microbes produce less atmospheric carbon dioxide than expected with climate warming

2010-04-28T23:43:00.001+05:30

Credit: Steven D. AllisonKey players in carbon cycle multiply slowly when overheated
In dark, rich soils on every continent, microbes dealing with the effects of climate change aren't accelerating global warming the way scientists had predicted, a study by researchers at the University of California at Irvine, Colorado State University and Yale University shows.

Results of the study appear in a paper published on-line this week in the journal Nature Geoscience. The work was supported by the National Science Foundation (NSF) and U.S. Department of Energy.

"Microbes continually surprise us in the diverse ways they respond to environmental conditions," said Saran Twombly, program director in NSF's Division of Environmental Biology, which funded the research along with NSF's Advancing Theory in Biology program, part of the Directorate for Biological Sciences Office of Emerging Frontiers.

"Microbes play a central role in ecological processes," said Twombly, "and their responses change our understanding of natural communities in fundamental ways."

Conventional scientific wisdom holds that even a few degrees of human-caused climate warming will shift fungi and bacteria that consume soil-based carbon into overdrive, and that their growth will accelerate the release of carbon dioxide into the atmosphere.

But a research team led by ecologist Steve Allison of UC Irvine took a closer look, and found something different.

While microbial soil decomposition, and resulting carbon dioxide emissions, increase initially, microbes eventually overheat and grow more slowly.

As their numbers decline, they release decreasing amounts of climate-warming greenhouse gases.

"Microbes are the engines that drive carbon cycling in soils," said Allison.

"In a balanced environment, plants store carbon in the soil and microbes use that carbon to grow. Enzymes produced by microbes convert soil carbon into atmospheric carbon dioxide."

A previous study by Mark Bradford of Yale and Matthew Wallenstein of Colorado State found that microbes became less efficient at decomposing soil carbon after several years of experimental warming.

They asked Allison to develop a computer model to test how adaptation of microbes to climate change might affect the carbon cycle.

"The issue we have in predicting whether soil carbon loss will accelerate climate warming is that the microbial processes causing this loss are poorly understood," said Bradford. "More research in this area will help reduce uncertainties in climate prediction."

In the resulting computer model, microbes became less efficient at converting their carbon food source into biomass as climate warmed.

In short, the microbes were not well adapted to a warmer climate. As their growth slowed, so did enzyme production.

"When we developed a model based on the actual biology of soil microbes, we found that soil carbon may not be lost to the atmosphere as the climate warms," Allison said. "Conventional ecosystem models that didn't include enzymes did not make the same predictions."

The next steps include studying more microbes and more ecosystems.

Microbes from a Massachusetts forest inspired this study, then Allison began collecting soil samples from California, Alaska, Maine and Costa Rica.

"Nearly one-third of all soil-based carbon is sequestered in permafrost or Arctic regions, which might respond differently to warming," said Wallenstein, who is researching sites in Greenland and Alaska.

"We need to develop more models to include microbe diversity," Allison said. "But the general principle that's important in our model is the decline of carbon dioxide production after an initial increase."

New study shows rising water temperatures in US streams and rivers

2010-04-06T19:42:00.000+05:30

New research by a team of ecologists and hydrologists shows that water temperatures are increasing in many streams and rivers throughout the United States. The research, published in the journal Frontiers in Ecology and the Environment, documents that 20 major U.S. streams and rivers – including such prominent rivers as the Colorado, Potomac, Delaware, and Hudson – have shown statistically significant long-term warming.

By analyzing historical records from 40 sites located throughout the United States, the team found that annual mean water temperatures increased by 0.02-0.14°F (0.009-0.077°C) per year. Long-term increases in stream water temperatures were typically correlated with increases in air temperatures, and rates of warming were most rapid in urbanized areas.

"Warming waters can impact the basic ecological processes taking place in our nation's rivers and streams," said Dr. Sujay Kaushal of the University of Maryland Center for Environmental Science (UMCES) and lead author of the study. "Long-term temperature increases can impact aquatic biodiversity, biological productivity, and the cycling of contaminants through the ecosystem."

"It's both surprising and remarkable that so many diverse river systems in North America behaved in concert with respect to warming," said Dr. David Secor of the UMCES Chesapeake Biological Laboratory whose work focused on Maryland's Patuxent River, where he has noted a 3°F increase since 1939.

The analysis indicates that 20 of the 40 streams studied showed statistically significant long term warming trends, while an additional 13 showed temperature increases that were not statistically significant. Two rivers showed significant temperature decreases. The longest record of increase was observed for the Hudson River at Poughkeepsie, New York. The most rapid rate of increase was recorded for the Delaware River near Chester, Pennsylvania.

"We are seeing the largest increases in the most highly urbanized areas which lead us to believe that the one-two punch of development and global warming could have a tremendous impact on stream and river ecosystem health," said Dr. Kaushal.

Given long-term global warming and "urban heat island effects" related to the abundance of buildings, roads, concrete, and asphalt, the authors point out that conserving riparian forests, reducing impervious surfaces, adopting "green" infrastructure practices, and reducing greenhouse gas emissions can help reduce increased water temperatures.

Even soil feels the heat

2010-03-26T01:18:00.001+05:30

Soils release more carbon dioxide as globe warms.

Twenty years of field studies reveal that as the Earth has gotten warmer, plants and microbes in the soil have given off more carbon dioxide. So-called soil respiration has increased about one-tenth of 1 per cent per year since 1989, according to an analysis of past studies in today's issue of Nature.

The scientists also calculated the total amount of carbon dioxide flowing from soils, which is about 10-15 per cent higher than previous measurements. That number – about 98 petagrams of carbon a year (or 98 billion metric tons) – will help scientists build a better overall model of how carbon in its many forms cycles throughout the Earth. Understanding soil respiration is central to understanding how the global carbon cycle affects climate.

"There's a big pulse of carbon dioxide coming off of the surface of the soil everywhere in the world," said ecologist Ben Bond-Lamberty of the Department of Energy's Pacific Northwest National Laboratory. "We weren't sure if we'd be able to measure it going into this analysis, but we did find a response to temperature."

The increase in carbon dioxide given off by soils – about 0.1 petagram (100 million metric tons) per year since 1989 – won't contribute to the greenhouse effect unless it comes from carbon that had been locked away out of the system for a long time, such as in Arctic tundra. This analysis could not distinguish whether the carbon was coming from old stores or from vegetation growing faster due to a warmer climate. But other lines of evidence suggest warming is unlocking old carbon, said Bond-Lamberty, so it will be important to determine the sources of extra carbon.

The Opposite of Photosynthesis

Plants are famous for photosynthesis, the process that stores energy in sugars built from carbon dioxide and water. Photosynthesis produces the oxygen we breathe as a byproduct. But plants also use oxygen and release carbon dioxide in the same manner that people and animals do. Soil respiration includes carbon dioxide from both plants and soil microbes, and is a major component of the global carbon cycle.

Theoretically, the biochemical reactions that plants and soil microbes engage in to produce carbon dioxide suggest that higher temperatures should result in more carbon dioxide being released. But unlike the amount of sunlight reaching Earth, soil respiration can't be measured from space and can't yet be simulated effectively with computer models.

So, the researchers turned to previous studies to see if they could quantify changes in global soil respiration. PNNL's Bond-Lamberty and his colleague Allison Thomson, working at the Joint Global Change Research Institute in College Park, Md., examined 439 soil respiration studies published between 1989 and 2008.

They compiled data about how much carbon dioxide has leaked from plants and microbes in soil in an openly available database. To maintain consistency, they selected only data that scientists collected via the now-standard methods of gas chromatography and infrared gas analysis. The duo compared 1,434 soil carbon data points from the studies with temperature and precipitation data in the geographic regions from other climate research databases.

After subjecting their comparisons to statistical analysis, the researchers found that the total amount of carbon dioxide being emitted from soil in 2008 was more than in 1989. In addition, the rise in global temperatures correlated with the rise in global carbon flux. However, they did not find a similar relation between precipitation and carbon.

Zooming In

Previous climate change research shows that Arctic zones have a lot more carbon locked away than other regions. Using the complete set of data collected from the studies, the team estimated that the carbon released in northern – also called boreal – and Arctic regions rose by about 7 per cent; in temperate regions by about 2 per cent; and in tropical regions by about 3 per cent, showing a trend consistent with other work.

The researchers wanted to know if their data could provide more detailed information about each region. So they broke down the complete data set by regional climates and re-examined the smaller groups of data using different statistical methods. The regional data from the temperate and tropical climates produced results consistent with other results, such as more carbon being released at higher temperatures, but the boreal-Arctic climate data did not. In addition, removing only 10 per cent of the boreal-Arctic data points was enough to invalidate the statistical significance of the boreal-Arctic result. Together, the results support the idea that more boreal data on regional climates is needed to reach statistical relevance.

"We identified an area where we need to do more work," said Thomson.

New boreal forest biomass maps produced from radar satellite data

2010-03-26T01:10:00.003+05:30

Boreal forest Having a large-scale boreal forest biomass inventory would allow scientists to understand better the carbon cycle and to predict more accurately Earth’s future climate. However, obtaining these maps has been wrought with difficulty – until now.

A new processing algorithm has been developed using stacks of images from the Advanced Synthetic Aperture Radar (ASAR) on ESA’s Envisat satellite that allows for the retrieval of boreal forest biomass well beyond the levels that have been previously reported.

Forests play a crucial role in Earth’s carbon cycle by absorbing carbon from the atmosphere and storing it in biomass. Undisturbed forests are carbon sinks as they absorb carbon, while forests that are logged or burnt down become carbon sources as they release carbon into the atmosphere.

“The maps are extremely important for providing effective forest fire protection monitoring”Boreal forests and woodlands are estimated to cover approximately 14.5% of Earth's land surface, comprising an area of nearly 16 million sq km (about the size of the contiguous 48 states of the US). The boreal forest ecosystem, which spans Russia, northern Europe, Canada and Alaska, comprises interrelated habitats made up of forests, lakes, wetlands, rivers and tundra.

Boreal forests – including forest soil – store a third more carbon stocks per hectare as tropical forests, making them one of the most significant carbon sinks in the world. These regions are considered global hotspots, i.e. areas of increased warming, which represent possible important tipping points for abrupt climate change.

"Biomass, one of the most essential climate variables defining the functions of the Earth system, is the big unknown factor in the carbon cycle. Since no biomass maps exist with a high level of accuracy, we do not know how much is changing and cannot do calculations with any certainty. With this new algorithm, it is the first time that we have something in hand that may be a first step to a global biomass map," said Prof. Christiane Schmullius with the Friedrich Schiller University Jena.

Forest growing stock volume (GSV) map of Sweden, obtained with the BIOMASAR algorithm using Envisat Advanced Synthetic Aperture Radar (ASAR) Global Monitoring mode images acquired in 2005 and 2006. GSV is represented in shades of green between 0–500 cubic metres per hectare. The GlobCover Land Cover map was used as background for non-forested areas. Map projection: Swedish National Grid (RT90).
Credits: ESA, Gamma Remote Sensing, Friedrich-Schiller University JenaThe BIOMASAR project, sponsored by ESA’s Support to Science Element (STSE), has fully validated the algorithm using ASAR data, which is capable of acquiring images regardless of darkness and cloud cover, with existing in-situ information. To validate the algorithm, several test sites were chosen in Scandinavia, Siberia and Canada, where both extensive datasets of ASAR images, acquired in ScanSAR mode at mid-resolution, and in-situ measurements were available.

The results show that the retrieval of forest growing stock volume (GSV) – the amount of wood expressed in cubic metres per hectare – is possible from Envisat ASAR data in boreal forests well beyond the levels that have been reported previously, i.e. up to 500 cubic metres per hectare.

Using this method, Envisat archives can be exploited to generate global maps of GSV yearly over the entire boreal ecozone with a resolution of 10 km and accuracies of 20%, while avoiding the problems associated with saturation usually encountered with C-band SAR retrievals at high biomass densities.

The Max Planck Institute for Biochemistry’s Dr Christian Beer, who will use the maps, said: "We are working with Earth System Models to try to project the future climate, and biological processes on land are of major importance for the Earth system. Biomass is the long-term result of ecophysiological processes such as photosynthesis and respiration, but it also changes quickly after disturbances or clear cutting.

Forest growing stock volume (GSV) map of Central Siberia, obtained with the BIOMASAR algorithm using one-year of Envisat Advanced Synthetic Aperture Radar (ASAR) Global Monitoring mode images acquired in 2005. GSV is represented in shades of green between 0–500 cubic metres per hectare. The GlobCover Land Cover map was used as the background for non-forested areas. Map projection: Albers (standard parallels 56 and 73 degree N).
Credits: ESA, Gamma Remote Sensing, Friedrich-Schiller University Jena"What is detected from ASAR data on the biomass is, therefore, vital for validating what we simulate, but could also be used for constraining parameters of the model."

To give an example of why it is so important to estimate the amount of organic matter in forests, Prof. Anatoly Shvidenko, Acting Leader of the Forestry Programme of the International Institute for Applied Systems Analysis, cited the catastrophic fire that occurred in Russia during 2003.

"The direct carbon emissions in Russia due to the wildfires were about 270 million tonnes. Compare that to the 250-million-tonne goal of emission reductions for the entire Kyoto Protocol, and it becomes very clear why it is extremely important to know what we have in terms of forest biomass.

"The maps are extremely important for providing effective forest fire protection monitoring and other important forest management activities. They could also be used for estimating many important factors that help explain how the Earth system functions. The algorithm shows unexpectedly good results."

Dr Maurizio Santoro of Gamma Remote Sensing, who developed the algorithm, said ASAR images play a crucial role in generating the maps.

"You cannot produce these maps with any other sensor now or in the near future. The reason for this is the spatial coverage of ASAR in ScanSAR mode and the global dataset of images available, going back seven years," he explained. "This is the first time that we can use available data and simple tools to obtain a spatially consistent description of forests that is satisfactory to users."

One might ask why the algorithm was not developed before, and the answer is surprisingly simple: no one else thought about it.

"ASAR acquires images in C-band, which does not have a wavelength long enough to provide the sensitivity needed for forests with marginal density. Dr Santoro realised that by combining multitemporal datasets the sensitivity gets better with respect to higher biomass classes," Prof. Schmullius explained.

"He found that with a minimum of 60 scenes, the level of noise is reduced so much that you get an excellent signal with respect to forest density. ESA is the only space agency that has data – historical and incoming – with this capability operating routinely on a global basis. We are desperately waiting for the launch of Sentinel-1, which will provide us the chance to produce even better maps."

Sentinel-1, planned for launch in 2011, will ensure the continuity of SAR data at large, with immediate priority for C-band data. It will operate in the ScanSAR mode with a much higher resolution as compared to ASAR. The fleet of five Sentinel satellites is being developed by ESA within the EU’s Global Monitoring for Environment and Security (GMES) initiative.

Using data from the ASAR archive, the validated algorithm can be applied over almost the entire Northern Boreal Forest Zone. It can also be employed to generate maps of land-use change and biomass loss. In the future, the BIOMASAR team hopes to expand the method to include temperate forest and savannah biomes and to update the maps yearly.

Greenland ice sheet losing mass on northwest coast

2010-03-26T00:58:00.000+05:30

Ice loss from the Greenland ice sheet, which has been increasing during the past decade over its southern region, is now moving up its northwest coast, according to a new international study.

Led by the Denmark Technical Institute's National Space Institute in Copenhagen and involving the University of Colorado at Boulder, the study indicated the ice-loss acceleration began moving up the northwest coast of Greenland starting in late 2005. The team drew their conclusions by comparing data from NASA's Gravity and Recovery Climate Experiment satellite system, or GRACE, with continuous GPS measurements made from long-term sites on bedrock on the edges of the ice sheet.

The data from the GPS and GRACE provided the researchers with monthly averages of crustal uplift caused by ice-mass loss. The team combined the uplift measured by GRACE over United Kingdom-sized chunks of Greenland while the GPS receivers monitor crustal uplift on scales of just tens of miles. "Our results show that the ice loss, which has been well documented over southern portions of Greenland, is now spreading up along the northwest coast," said Shfaqat Abbas Khan, lead author on a paper that will appear in Geophysical Research Letters.

The team found that uplift rates near the Thule Air Base on Greenland's northwest coast rose by roughly 1.5 inches, or about 4 centimeters, from October 2005 to August 2009. Although the low resolution of GRACE - a swath of about 155 miles, or 250 kilometers across - is not precise enough to pinpoint the source of the ice loss, the fact that the ice sheet is losing mass nearer to the ice sheet margins suggests the flows of Greenland outlet glaciers there are increasing in velocity, said the study authors.

"When we look at the monthly values from GRACE, the ice mass loss has been very dramatic along the northwest coast of Greenland," said CU-Boulder physics Professor and study co-author John Wahr, also a fellow at CU-Boulder's Cooperative Institute for Research in Environmental Sciences.

"This is a phenomenon that was undocumented before this study," said Wahr. "Our speculation is that some of the big glaciers in this region are sliding downhill faster and dumping more ice in the ocean."

Other co-authors on the new GRL study included Michael Bevis and Eric Kendrick from Ohio State University and Isabella Velicogna of the University of California-Irvine, who also is a scientist at NASA's Jet Propulsion Laboratory. GRL is published by the American Geophysical Union.

A 2009 study published in GRL by Velicogna, who is a former CU-Boulder research scientist, showed that between April 2002 and February 2009, the Greenland ice sheet shed roughly 385 cubic miles of ice. The mass loss is equivalent to about 0.5 millimeters of global sea-level rise per year.

"These changes on the Greenland ice sheet are happening fast, and we are definitely losing more ice mass than we had anticipated, " said Velicogna. "We also are seeing this ice mass loss trend in Antarctica, a sign that warming temperatures really are having an effect on ice in Earth's cold regions."

Researchers have been gathering data from GRACE since NASA launched the system in 2002. Two GRACE satellites whip around Earth 16 times a day separated by 137 miles and measure changes in Earth's gravity field caused by regional shifts in the planet's mass, including ice sheets, oceans and water stored in the soil and in underground aquifers.

"GRACE is unique in that it allows us to see changes in the ice mass in almost real time," said Velicogna. "Combining GRACE data with the separate signals from GPS stations gives us a very powerful tool that improves our resolution and allows us to better understand the changes that are occurring."

In addition to monitoring the Thule GPS receiver in northwest Greenland as part of the new GRL study, the team also is taking data from GPS receivers in southern Greenland near the towns of Kellyville and Kulusuk. An additional 51 permanent GPS stations recently set up around the edges of the Greenland ice sheet should be useful to measure future crustal uplift and corresponding ice loss, said Wahr.

"If this activity in northwest Greenland continues and really accelerates some of the major glaciers in the area - like the Humboldt Glacier and the Peterman Glacier - Greenland's total ice loss could easily be increased by an additional 50 to 100 cubic kilometers (12 to 24 cubic miles) within a few years," said Khan.

Global warming threatens plant diversity

2010-03-26T00:55:00.000+05:30

Senecio inaequidens, a plant native to the mountains of South Africa, has been spreading rapidly along the roads and railway embankments in Germany since the 1950s.In the coming decades, climate change is set to produce worldwide changes in the living conditions for plants, whereby major regional differences may be expected to occur. Thus today´s cool, moist regions could in future provide habitats for additional species, and in arid and hot regions the climatic prerequisites for a high degree of plant diversity will deteriorate. This is the conclusion reached in a new study by scientists at the Universities of Bonn, Göttingen and Yale, and published in the Proceedings of the Royal Society London. The study was funded by the Academy of Sciences and Literature Mainz and the German Federal Ministry for Education and Research (BMBF).

Dr. Jan Henning Sommer of Bonn University´s Nees Institute for Biodiversity of Plants asserts, "climate change could bring great confusion to the existing pattern of plant diversity, with scarcely predictable consequences for our ecosystems and mankind". The potential impact of climate change on global plant diversity has now, for the first time, been quantified and modeled on a regional basis. The researchers have investigated the numbers of plant species to be found in different regions under current climatic conditions, and the subsequent interrelationship they uncovered has now been applied to 18 different climate change scenarios for the year 2100.

Senecio inaequidens, a plant native to the mountains of South Africa, has been spreading rapidly along the roads and railway embankments in Germany since the 1950s. According to the study, climate change could provide habitat space for additional species in cool and temperate regions worldwide, which may then become strong competitors for native species.
Credit: © W. Barthlott, University of BonnHowever, the study does not permit any predictions regarding the degree to which the biodiversity of any given region will, in fact, adapt to new conditions or, in other words, whether additional species will migrate into favoured regions, or whether disadvantaged areas will in reality suffer mass losses of species. "That would be fortune-telling. The adaptability of species and their interactions in the ecosystem can, like human landuse, exert great influence on their distribution. This is a field about which we still know far too little", Sommer explains. Nevertheless, the published results do provide an important pointer to the likelihood of the scales of immigration or losses to be expected in given areas.

Globalisation in the Plant Kingdom

Climate change will have a clear impact on plant diversity worldwide. Today's cool and moist areas could in future offer habitats for additional species (green areas on the maps), in arid and hot regions the climatic prerequisites for a high species richness will deteriorate (orange-red areas on the maps). The illustration shows a comparison of the conservative 1.8°C scenario (IPCC B1) and a 4.0°C scenario (IPCC A1FI) which, if present climate policy is maintained, is clearly the more likely.
Credit: (c) University of BonnIt is possible that the worst effects of global warming on plant species numbers could be felt in the tropical Amazonian rain forests in South America. For Germany and other temperate regions worldwide, on the other hand, scientists are expecting future climatic conditions which will promote the provision of habitat space for an increased number of species. "But this can scarcely be described as a gain as the intensified redistribution of plant species will promote worldwide uniformity in the regional composition of species at the expense of unique species which have adapted to special habitat conditions", says Sommer. And as a result, globalisation would also come to the plant kingdom.

In their study, the researchers have emphasised the clear division of our planet into two parts as regards the impact of climate change on plant diversity. "Additional capacity for plants species richness could be created everywhere where today cool and moist climatic conditions prevail", says Dr. Holger Kreft, the young research scientist from Bonn and co-author of the study, who has meanwhile assumed an appointment as junior professor at Göttingen University." On the other hand, in areas which today have a hot tropical or sub-tropical climate the prerequisites for high species numbers will deteriorate".

The main Originators of Climate Change less affected

This division also has a political dimension: favoured areas coincide largely with the industrialised nations, who are responsible for the majority of global warming due to their high amount of greenhouse gas emissions. The study also points clearly to the consequences of a half-hearted climate policy. Should the global temperature rise by 1.8°C with respect to the year 2000, then the proportion of favoured and disadvantaged regions in terms of species richness would still remain in balance. "Even if the climate protection goals agreed in Copenhagen are achieved, we would still tend to be heading for a rise in temperature of up to 4°C", says Sommer. In this case, the projected losses of capacity for plant species richness would considerably exceed possible gains in other regions.

"Politicians throughout the world should be paying greater attention to the impact of climate change on biodiversity as this is the basis of our human existence", demands Professor Dr. Wilhelm Barthlott, Director of the Nees Institute and co-author of the study. He and his study group have been investigating global plant diversity for 15 years. Barthlott welcomes the fact that the United Nations has declared 2010 to be the year of biodiversity. "This was an important signal!".

Earth Hour 2010 in the UAE

2010-03-24T17:47:00.010+05:30

Earth Hour, a global event created to symbolise that each one of us, working together, can make a difference on climate change, will take place on Saturday March 27th at 8.30 PM.

The world’s tallest building Burj Khalifa and the resting place of the UAE’s founding father, the Sheikh Zayed Bin Sultan Al Nahyan Mosque will join other iconic UAE landmarks including, the Emirates Palace, Raffles Hotel, ADIA Building, Burj Al Arab, Jumeirah Emirates Towers, Aldar Head Quarters, Sharjah Mega Mall, Sharjah Science Museum, Fairmont, Tecom, Media One Hotel, Dubai World Trade centre, the Yas Hotel and Yas Marina Circuit, Sas Radisson Hotel Blue and more for Earth Hour and ‘flick the switch’ on their signature landmarks, marking their dedication to sustainable development and joining their citizens in adopting low-carbon practices switching off the lights in a decisive display of climate action.

“The actions shown by business and community leaders are crucial to leading a low-carbon resolution to climate change, says EWS-WWF Managing Director, Razan Khalifa Al Mubarak.”

“The UAE has one of the highest ecological footprints per capita, so our role in addressing what is unequivocally the greatest threat to the planet today is absolutely vital,” Al Mubarak said.”

As Earth Hour has grown from a one-city initiative in 2007 to a global phenomenon in 2009, renowned icons, including the Great Pyramids, Eiffel Tower, the Coliseum, Christ the Redeemer statue, Buckingham Palace and many more have joined the global community in showing leadership on a resolution to climate change.

In the UAE, the participation from the government and private sector has exceeded last years with over 150 organisations signed up, and EWS-WWF is expecting thousands of residents to participate either at home, at one of the Earth hour events or simply by turning off all electricity before going out to the horse race, the music festival or to attend a candle light dinner at a restaurant.

Ida Tillisch of EWS-WWF said, “It is very encouraging to see the number of Earth Hour participants increase every day. People and organisations concerned about climate change are signing up and many are going out of their way to help promote the campaign further. We are hopeful of Earth Hour participation in all seven emirates, as UAE residents from every walk of life, in communities large and small, symbolically dim their lights in solidarity for climate action with hundreds of millions of people around the world.”

In Abu Dhabi and Dubai Earth Hour events and gathering are being planned, for example in Dubai, DEWA will be leading a lantern march on Beach Road, which will be partly closed for traffic during Earth Hour.

Amal Koshak, Senior Manager, Demand and Tariff Management at DEWA said “Earth Hour is an inspiring message of hope and action and we are encouraging all residents and organisations to participate. Participation does not necessarily mean you have to sit at home without lights and TV, we encourage people join Earth Hour on Beach Road for our lantern march, but do turn all electricity off at home before you leave. In 2009, Earth Hour in Dubai brought a reduction in power consumption of 146,000kW/h (kilo-watt-hour), this year we aim for more and encourage people to turn off all unnecessary electric equipment including their air conditioners for Earth Hour.”

H.E Hamad Buamim, director general, Dubai Chamber said, “We would like to take this opportunity to encourage organisations and their staff to reduce their consumption of electricity throughout the year. By doing so, we can all play a role in helping our nation address energy challenges and climate change. Dubai Chamber supports Earth Hour and other initiatives aiming at preserving our environment, promoting sustainability and making our communities a better place to work and live in.”

Ahmad Al Matrooshi, Managing Director – UAE, Emaar Properties said, “Emaar is proud to support Earth Hour and is committed to partnering in initiatives that promote environmental awareness.

As a pioneer of integrated lifestyle communities, Emaar has been at the forefront in creating sustainable communities through a focus on the efficient use of resources. We believe that meaningful change can be brought about through community action, and we are taking the lead by participating in Earth Hour.”

The Abu Dhabi Future Energy Company, Masdar will be participating in Earth Hour and is helping to promote the initiative. Dr. Naal Al Hosany, Director, Sustainability, Masdar said, “Earth Hour is about responsibility, about the duty that all of us – as individuals, as families, as companies and organizations and as nations – have to protect our environment and to take action against climate change. Switching off the lights for one hour reinforces that message and shows how simple actions can go a long way toward making a difference; its very encouraging that more and more individuals and entities from the UAE participate in Earth Hour each year.”

“Earth Hour is not just about one night, it is about highlighting the possibilities for change and encouraging long term actions that will reduce the carbon footprints of individuals, groups, companies, governments, and nations, on both the date of Earth Hour and on a continuing permanent basis” explains Al Mubarak.

With the confirmed participation of citizens from 118 countries and regions, Earth Hour is anticipated to be the greatest civil action the world has ever witnessed, a global team hundreds of millions strong that will show the world what can be done.

From climate change to securing sustainable employment: key issues facing the Arab region

2010-03-16T18:30:00.003+05:30

UNEP-Led "Environment Outlook for the Arab Region" launched at League of Arab States meeting in Cairo

Multiple challenges are facing the Arab region from climate change and food insecurity to decreasing water availability and unemployment according to a new assessment by the United Nations Environment Programme (UNEP).

The Environment Outlook for the Arab Region (EOAR), compiled at the request of the Council of Arab Ministers Responsible for the Environment (CAMRE) says important progress is being made to address sustainability.

Much of the progress has focused on the development of the environmental frameworks including the necessary legislation alongside improved public awareness and involvement of countries in the region in international treaties and agreements.

The focus now is to translate these institutional gains into transformative action across countries and on the ground in order to catalyze a transition to a low carbon, resource efficient Green Economy.

Achim Steiner, UN Under-Secretary General and UNEP Executive Director, said, "This assessment has been a truly collaborative one outlining the progress but also the realities facing this diverse but also dynamic region where if policies and resources are better focused could be a beacon of sustainable, Green Economic, development for millions of people".

"One factor that is both a persistent but also an emerging challenge is water. The EOAR notes that Arab countries are now among most water-scarce in the world and that there has been a worrying decline in per capita water availability with an average of only 1 000 m3 per inhabitant per year, as of 2008," he added.

"Climate change is likely to aggravate these trends. Thus it is in the interests of nations across the region to constructively engage in the climate change negotiations as countries look to Mexico and the UN climate convention meeting later in the year," said Mr Steiner.

He said a transformation towards a low carbon, resource efficient path offered the best opportunity for not only addressing challenges but delivering opportunities in terms of diversified energy supplies, security of natural resources and the chance to generate new kinds of jobs in areas such as clean energy and natural resource management.

The new report, launched at the headquarters of the League of Arab States in Cairo, has been prepared in collaboration with the General Secretariat of the League of Arab States (LAS), the Center for Environment and Development for the Arab Region and Europe (CEDARE), as well as the Arab Specialized agencies and Global Environment Outlook collaborating centers in the region.

It notes that biofuels and food security are among a suite of emerging and intertwined challenges facing the region.

Poverty remains a challenge in most countries in the region and unemployment is wide spread at 13.7 per cent or more than twice the global average, according to the latest estimates.

The report says the Arab region is predicted to be among the hardest hit by the potential of direct and indirect impacts linked with climate change.

Impacts include loss of coastal zones, more severe droughts and desertification, increased groundwater salinity, and a surge in epidemics and infectious diseases.

Dr. Nadia Makram Ebeid, CEDARE Executive Director stresses, "The interlinked environmental challenges facing the Arab region are enormous, but also represent an opportunity for development. There is no contradiction between protecting the environment and achieving economic development. Solving environmental problems contributes eventually to the elimination of a large number of obstacles facing development" she says.

The report affirms that the region's natural resources offer a wide ranging opportunities, if these resources are used rationally and sustainably, and if environmental aspects are integrated into the decision making process.

Southern Ocean winds open window to the deep sea

2010-03-15T20:23:00.000+05:30

Photo: Alicia NavidadAustralian and US scientists have discovered how changes in winds blowing on the Southern Ocean drive variations in the depth of the surface layer of sea water responsible for regulating exchanges of heat and carbon dioxide between the ocean and the atmosphere.

The researchers’ findings – published on-line today in Nature Geoscience – provide new insights into natural processes which have a major influence on the rate of climate change.

The surface-mixed layer is a crucial pathway between the atmosphere and the deeper layers of the ocean. Changes in the depth of the mixed layer can affect air-sea exchange, carbon and heat storage in the ocean, and the rate at which water sinks from the surface ocean into the deep ocean.

Changes in the mixed layer also affect biological productivity, by altering how much light and nutrients are available to support growth of plankton at the base of the food chain.

The paper’s lead author, CSIRO Wealth from Oceans Flagship oceanographer Dr Jean-Baptiste Sallée, said the winds over the Southern Ocean had increased in strength and shifted closer to Antarctica in recent decades.

“The shift in winds is one of the strongest trends in southern hemisphere climate over the last 30 years,” Dr Sallée said. “The key question is; ‘How does the wind change affect the ocean?’

“Our knowledge of how the Southern Ocean changes in time is poor because of the lack of ship-based observations in this remote region. But we now have seven years of year-round observations from a fleet of profiling floats known as Argo, which allow us to see for the first time how the Southern Ocean changes with the seasons and from year-to-year.”

The researchers, including Dr Steve Rintoul from the Antarctic Climate and Ecosystems CRC and CSIRO and Professor Kevin Speer from Florida State University, examined the relationship between changes in wind and changes in the surface-mixed layer.

“We found that the depth of the mixed layer was more sensitive than we expected to a wind pattern known as the Southern Annular Mode, the major mode of variability of the southern hemisphere atmosphere,” Dr Sallée said. “Even more surprising was the fact that the response is very different in different regions.”

When the winds strengthen and contract closer to Antarctica, the surface-mixed layer deepens in the eastern Indian and central Pacific oceans, and shallows in the western part of these basins. The reverse is seen when the winds weaken and migrate north.

The asymmetry can be explained by small deviations in the generally west-to-east winds and their effect on the heat exchange between ocean and atmosphere: when cold winds blow from the south, this causes heat loss from the ocean and deeper mixed layers.

“These changes in mixed layer depth affect how much light is available to support the growth of phytoplankton. We found that changes in the mixed layer depth driven by the winds are associated with changes in the amount of phytoplankton biomass,” Dr Sallée said.

Climate now: New state of the Climate Snapshot

2010-03-15T19:28:00.002+05:30

More extremely hot days, fewer cold ones wetter in the north and drier in the south: this is not a forecast for Australia’s climate but a snapshot of the climate now.

In a joint CSIRO/Bureau of Meteorology statement released today, Australia’s two lead climate science agencies have produced a snapshot of the state of the climate to update Australians about how their climate has changed and what it means.

Changes observed include:

Highly variable rainfall across the country, with substantial increases in rainfall in northern and central parts of Australia, as well as significant decreases across much of southern and eastern Australia.

Rapidly rising sea levels from 1993 to 2009, with levels around Australia rising, between 1.5cm and 3cm per decade in Australia’s south and east and between 7cm and 9cm in the country’s north

About half of the observed reduction in winter rainfall in south-west Western Australia can be explained by higher greenhouse gas levels.

Bureau of Meteorology Director Dr Greg Ayers said the observed changes showed climate change was real.

“Australia holds one of the best national climate records in the world,” Dr Ayers said.

“The Bureau’s been responsible for keeping that record for more than a hundred years and it’s there for anyone and everyone to see, use and analyse.”

CSIRO chief executive Dr Megan Clark said the Bureau data underpinned a great deal of CSIRO research.

“Understanding options for mitigation and adaptation are important research priorities for us,” Dr Clark said.

“With this snapshot, Australians will be better prepared for the next step of planning for how to adapt to a changing climate and how to also take action to reduce the impacts of climate change. CSIRO has been working with industry and in sectors of the economy such as agriculture to prepare for and implement necessary changes.”

Dr Ayers said the snapshot presented the facts in an accessible format.

“There is a thirst for good quality climate science and our two organisations are proud to publish this,” he said.

Arctic seabed methane stores destabilising, venting

2010-03-07T03:15:00.003+05:30

A section of the Arctic Ocean seafloor that holds vast stores of frozen methane is showing signs of instability and widespread venting of the powerful greenhouse gas, according to the findings of an international research team led by University of Alaska Fairbanks scientists Natalia Shakhova and Igor Semiletov.

The research results, published in the March 5 edition of the journal Science, show that the permafrost under the East Siberian Arctic Shelf, long thought to be an impermeable barrier sealing in methane, is perforated and is leaking large amounts of methane into the atmosphere. Release of even a fraction of the methane stored in the shelf could trigger abrupt climate warming.

“The amount of methane currently coming out of the East Siberian Arctic Shelf is comparable to the amount coming out of the entire world’s oceans,” said Shakhova, a researcher at UAF’s International Arctic Research Center. “Subsea permafrost is losing its ability to be an impermeable cap.”

Methane is a greenhouse gas more than 30 times more potent than carbon dioxide. It is released from previously frozen soils in two ways. When the organic material—which contains carbon—stored in permafrost thaws, it begins to decompose and, under oxygen-free conditions, gradually release methane. Methane can also be stored in the seabed as methane gas or methane hydrates and then released as subsea permafrost thaws. These releases can be larger and more abrupt than those that result from decomposition.

The East Siberian Arctic Shelf is a methane-rich area that encompasses more than 2 million square kilometers of seafloor in the Arctic Ocean. It is more than three times as large as the nearby Siberian wetlands, which have been considered the primary Northern Hemisphere source of atmospheric methane. Shakhova’s research results show that the East Siberian Arctic Shelf is already a significant methane source: 7 teragrams yearly, which is equal to the amount of methane emitted from the rest of the ocean. A teragram is equal to about 1.1 million tons.

“Our concern is that the subsea permafrost has been showing signs of destabilization already,” she said. “If it further destabilizes, the methane emissions may not be teragrams, it would be significantly larger.”

Shakhova notes that Earth’s geological record indicates that atmospheric methane concentrations have varied between about .3 to .4 parts per million during cold periods to .6 to .7 parts per million during warm periods. Current average methane concentrations in the Arctic average about 1.85 parts per million, the highest in 400,000 years, she said. Concentrations above the East Siberian Arctic Shelf are even higher.

The East Siberian Arctic Shelf is a relative frontier in methane studies. The shelf is shallow, 50 meters or less in depth, which means it has been alternately submerged or terrestrial, depending on sea levels throughout Earth’s history. During Earth’s coldest periods, it is a frozen arctic coastal plain, and does not release methane. As the planet warms and sea levels rise, it is inundated with seawater, which is 12-15 degrees warmer than the average air temperature.

“It was thought that seawater kept the East Siberian Arctic Shelf permafrost frozen,” Shakhova said. “Nobody considered this huge area.”

Earlier studies in Siberia focused on methane escaping from thawing terrestrial permafrost. Semiletov’s work during the 1990s showed, among other things, that the amount of methane being emitted from terrestrial sources decreased at higher latitudes. But those studies stopped at the coast. Starting in the fall of 2003, Shakhova, Semiletov and the rest of their team took the studies offshore. From 2003 through 2008, they took annual research cruises throughout the shelf and sampled seawater at various depths and the air 10 meters above the ocean. In September 2006, they flew a helicopter over the same area, taking air samples at up to 2,000 meters in the atmosphere. In April 2007, they conducted a winter expedition on the sea ice.

They found that more than 80 percent of the deep water and greater than half of surface water had methane levels more than eight times that of normal seawater. In some areas, the saturation levels reached at least 250 times that of background levels in the summer and 1,400 times higher in the winter.

They found corresponding results in the air directly above the ocean surface. Methane levels were elevated overall and the seascape was dotted with more than 100 hotspots. This, combined with winter expedition results that found methane gas trapped under and in the sea ice, showed the team that the methane was not only being dissolved in the water, it was bubbling out into the atmosphere.

These findings were further confirmed when Shakhova and her colleagues sampled methane levels at higher elevations. Methane levels throughout the Arctic are usually 8 to 10 percent higher than the global baseline. When they flew over the shelf, they found methane at levels another 5 to 10 percent higher than the already elevated arctic levels.

The East Siberian Arctic Shelf, in addition to holding large stores of frozen methane, is more of a concern because it is so shallow. In deep water, methane gas oxidizes into carbon dioxide before it reaches the surface. In the shallows of the East Siberian Arctic Shelf, methane simply doesn’t have enough time to oxidize, which means more of it escapes into the atmosphere. That, combined with the sheer amount of methane in the region, could add a previously uncalculated variable to climate models.

“The release to the atmosphere of only one percent of the methane assumed to be stored in shallow hydrate deposits might alter the current atmospheric burden of methane up to 3 to 4 times,” Shakhova said. “The climatic consequences of this are hard to predict.”

Shakhova, Semiletov and collaborators from 12 institutions in five countries plan to continue their studies in the region, tracking the source of the methane emissions and drilling into the seafloor in an effort to estimate how much methane is stored there.

New evidence hints at global glaciation 716.5 million years ago

2010-03-07T03:14:00.003+05:30

In this photo from Canada's Yukon Territory, an iron-rich layer of 716.5-million-year-old glacial deposits (maroon in color) is seen atop an older carbonate reef (gray in color) that formed in the tropics.

Credit: Francis A. Macdonald/Harvard UniversityGeologists have found evidence that sea ice extended to the equator 716.5 million years ago, bringing new precision to a "snowball Earth" event long suspected to have taken place around that time.

Led by scientists at Harvard University, the team reports on its work this week in the journal Science. The new findings - based on an analysis of ancient tropical rocks that are now found in remote northwestern Canada - bolster the theory that our planet has, at times in the past, been ice-covered at all latitudes.
"This is the first time that the Sturtian glaciation has been shown to have occurred at tropical latitudes, providing direct evidence that this particular glaciation was a 'snowball Earth' event," says lead author Francis A. Macdonald, an assistant professor in the Department of Earth and Planetary Sciences at Harvard. "Our data also suggests that the Sturtian glaciation lasted a minimum of 5 million years."

The survival of eukaryotic life throughout this period indicates sunlight and surface water remained available somewhere on the surface of Earth. The earliest animals arose at roughly the same time, following a major proliferation of eukaryotes.

Even in a snowball Earth, Macdonald says, there would be temperature gradients on Earth and it is likely that ice would be dynamic: flowing, thinning, and forming local patches of open water, providing refuge for life.

"The fossil record suggests that all of the major eukaryotic groups, with the possible exception of animals, existed before the Sturtian glaciation," Macdonald says. "The questions that arise from this are: If a snowball Earth existed, how did these eukaryotes survive? Moreover, did the Sturtian snowball Earth stimulate evolution and the origin of animals?"

"From an evolutionary perspective," he adds, "it's not always a bad thing for life on Earth to face severe stress."

The rocks Macdonald and his colleagues analyzed in Canada's Yukon Territory showed glacial deposits and other signs of glaciation, such as striated clasts, ice rafted debris, and deformation of soft sediments. The scientists were able to determine, based on the magnetism and composition of these rocks, that 716.5 million years ago they were located at sea level in the tropics, at about 10 degrees latitude.

"Because of the high albedo of ice, climate modeling has long predicted that if sea ice were ever to develop within 30 degrees latitude of the equator, the whole ocean would rapidly freeze over," Macdonald says. "So our result implies quite strongly that ice would have been found at all latitudes during the Sturtian glaciation."

Scientists don't know exactly what caused this glaciation or what ended it, but Macdonald says its age of 716.5 million years closely matches the age of a large igneous province stretching more than 1,500 kilometers (932 miles) from Alaska to Ellesmere Island in far northeastern Canada. This coincidence could mean the glaciation was either precipitated or terminated by volcanic activity.

Climate change one factor in malaria spread

2010-03-06T23:08:00.000+05:30

Climate change is one reason malaria is on the rise in some parts of the world, new research finds, but other factors such as migration and land-use changes are likely also at play. The research, published in The Quarterly Review of Biology, aims to sort out contradictions that have emerged as scientists try to understand why malaria has been spreading into highland areas of East Africa, Indonesia, Afghanistan and elsewhere.

"We assessed … conclusions from both sides and found that evidence for a role of climate in the dynamics is robust," write study authors Luis Fernando Chaves from Emory University and Constantianus Koenraadt of Wageningen University in the Netherlands. "However, we also argue that over-emphasizing a role for climate is misleading for setting a research agenda, even one which attempts to understand climate change impacts on emerging malaria patterns."

Malaria, a parasitic disease spread to humans by mosquitoes, is common in warm climates of Africa, South America and South Asia. The development and survival, both of the mosquito and the malaria parasite are highly sensitive to daily and seasonal temperature patterns and the disease has traditionally been rare in the cooler highland areas. Over the last 40 years, however, the disease has been spreading to the highlands, and many studies link the spread to global warming. But that conclusion is far from unanimous. Other studies have found no evidence of warming in highland regions, thus ruling out climate change as a driver for highland malaria.

Chaves and Koenraadt re-examined more than 70 of these studies. They found that the studies ruling out a role for climate change in highland malaria often use inappropriate statistical tools, casting doubt on their conclusions.

For example, an oft-cited 2002 study of the Kericho highlands of western Kenya found no warming trend in the area. But when Chaves and Koenraadt ran the same temperature data from that study through three additional statistical tests, each test indicated a significant warming trend. Similar statistical errors plague other comparable studies, the researchers say.

In contrast, most studies concluding that climate change is indeed playing a role in highland malaria tend to be statistically strong, Chaves and Koenraadt found. But just because climate is one factor influencing malaria's spread does not mean it is the only one. What is needed, the researchers say, is a research approach that combines climate with other possible factors.

"Even if trends in temperature are very small, organisms can amplify such small changes and that could cause an increase parasite transmission," Chaves said. "More biological data will improve our overall understanding of malaria and will allow scientists to propose more general and accurate models on the impacts of climate change on malaria transmission."

The authors cite numerous factors that could interact with climate to influence malaria spread. They point to research showing that people migrating from lowlands may be introducing the malaria parasite into highland regions. Changes in farming practices may also play a role. Irrigation associated with more intensive farming may be creating more places for mosquitoes to breed. Another example comes from two studies that linked malaria increases in the Bure highlands of Ethiopia to increased maize farming. There, the immature and aquatic stages of mosquitoes thrive on a diet of maize pollen, and more mosquitoes can mean more malaria.

"A major future challenge will be to link up what happens with mosquitoes and parasites at the household level with long-term climate change scenarios at the continental scale," Koenraadt said.

The spread of malaria in highlands is of great concern to those who work to contain the disease. But understanding the many factors that influence the spread of highland malaria could help with efforts to control the disease worldwide, Chaves and Koenraadt conclude.

"In the light of global efforts towards malaria elimination, highland areas will be interesting starting points from where control efforts could interrupt transmission and aid in shrinking the world's malaria map." Koenraadt said.

Improved near-real-time tracking of 2010 El Niño reveals marine life reductions

2010-03-04T12:36:00.002+05:30

Researchers search for answers to warming coastal water, thinning marine populations

The ongoing El Niño of 2010 is affecting north Pacific Ocean ecosystems in ways that could affect the West Coast fishing industry, according to scientists at NOAA and Scripps Institution of Oceanography, UC San Diego.

Researchers with the California Cooperative Oceanic Fisheries Investigations (CalCOFI) at Scripps and NOAA's Southwest Fisheries Science Center report a stronger than normal northward movement of warm water up the Southern California coast, a high sea-level event in January and low abundances of plankton and pelagic fish - all conditions consistent with El Niño.

Sea surface temperatures along the entire West Coast are 0.5 to 1 degree Celsius (0.9 to 1.8 degrees Fahrenheit) warmer than normal and at points off Southern California are as much as 1.6 degrees Celsius (2.9 degrees Fahrenheit) higher than normal. The most unusually high temperatures were mapped around Catalina and San Clemente islands. While strong winter storms caused an increase in coastal sea levels, scientists are investigating whether the higher sea levels are primarily a result of El Niño, a cyclical phenomenon characterized by warming eastern equatorial Pacific Ocean waters.

"Based on our previous experience of El Niño in California, it is likely to reduce ocean production below normal, with possible effects extending to breeding failure of seabirds, and much lower catches in the market squid fishery," said Sam McClatchie, a fisheries oceanographer at NOAA's Southwest Fisheries. "However, predictions are never certain, and CalCOFI and NOAA ocean-observing systems will continue to provide essential monitoring of the situation."

A combination of satellite remote sensing and field measurements is offering scientists a broader view of the evolution of this El Niño that was not available during previous El Niños, which were especially strong in 1982-83 and 1997-98. Internet technology aboard CalCOFI research vessels is delivering that information faster.

"You can post data the same day it's collected," said CalCOFI information manager Jim Wilkinson of Scripps Oceanography. "It used to take six months to work up some of the data and interpret it."

NOAA Southwest Fisheries oceanographer Frank Schwing said scientists' analytical tools provide better ways to assess the strength of anomalies such as warming that are associated with El Niño.

"We're taking a much more ecosystem-based approach to managing the system," said Schwing. "Because we are more on top of the observations, we can give a more timely heads-up to scientists and managers who are interested in the effects of El Niño."

The two research centers use data collected by satellites and buoy-mounted instruments to measure sea surface temperature. CalCOFI researchers embark on quarterly cruises off the California coast to collect vertical temperature profiles in the upper reaches of the water column. They also count eggs of commercially important fishes such as sardines and anchovies as well as measure plankton volumes to estimate the amount of "production" available to marine organisms. NOAA's Advanced Survey Technologies Group assesses fish populations through acoustic surveys. In contrast with the last major El Niño, Scripps now deploys Spray gliders, diving robots that now gather ocean temperature and other data along transects between CalCOFI stations.

The NOAA and CalCOFI scientists have observed a drop in biological abundance, or productivity, that appears to be related to the northward movement of warm water from the equator. The flow arrives in pulsing Kelvin waves that are detected by sea level and altimeter monitors and coastal tidal gauges. The layer of warm water often stifles the upwelling of nutrients from lower ocean depths that sustain larger populations of fishes and invertebrates.

The researchers reported finding fewer hake and anchovy eggs than usual in the most recent CalCOFI surveys. Sanddab and flounder eggs dominated the samples. Most were collected in a small area east of the Channel Islands.

The scientists added that if El Niño conditions continue, they are likely to be characterized by weaker than normal upwelling and lower biological production. El Niño conditions are forecast to persist into spring. If so, greater biological anomalies than have already been observed may develop.

World environment ministers signal resolve to realize sustainable development

2010-02-28T02:07:00.002+05:30

In the first landmark Declaration issued by ministers of the environment in a decade, governments pledged to step up the global response to the major environmental and sustainability challenges of this generation.

The wide-ranging Nusa Dua Declaration, agreed today in the closing session of the UN Environment Programme's (UNEP) Governing Council/Global Ministerial Environment Forum, underlines the vital importance of biodiversity, the urgent need to combat climate change and work towards a good outcome in Mexico later in the year and the key opportunities from accelerating a transition to a low-carbon resource-efficient Green Economy.

The statement also highlights the need to improve the overall management of the global environment, accepting that that 'governance architecture' has in many ways become too complex and fragmented.

An important step forward was made earlier in the week in the areas of chemicals, hazardous wastes and human health. Governments agreed at an Extraordinary Meeting to have more cooperative action by the three relevant treaties-the Basel, Rotterdam and Stockholm conventions - as a first step to boosting their delivery within countries.

Achim Steiner, UN Under-Secretary and UNEP Executive Director, said: "The ministers responsible for the environment, meeting just over a month after the climate change conference in Copenhagen, have spoken with a clear, united and unequivocal voice."

"Faced with the continued erosion of the natural environment, the persistent and emerging challenges of chemical pollution and wastes and the overarching challenge of issues such as climate change, the status quo is not an option and change is urgently needed," he added.

"This change starts with recognition that the way we are managing the environmental dimension of sustainable development is currently too complex and fragmented. Change is needed here and the ministers signaled their determination to realize this through a political process," said Mr. Steiner.

"But the ministers also recognized that action towards a Green Economy - one able to meet multiple challenges and seize multiple opportunities- is taking route in economies across the globe. Accelerating this is a key element of the Nusa Dua Declaration and one that can direct future action towards realising the kinds of transitions needed on a planet of six billion people, rising to nine billion by 2050," he added.

The Declaration, the first by world environment ministers since they met in Malmö, Sweden in 2000, will be transmitted to the UN General Assembly later this year.

There governments will begin preparations for a landmark conference in Brazil, called Rio plus 20.

Rio plus 20 comes two decades after the first Rio Earth Summit, which gave birth to many of the key treaties, ranging from climate change to biodiversity, which to date have defined the international response to environmental challenges.

Green Economy

Case studies, illuminating the multiple benefits of a Green Economy, were presented to delegates in advance of a landmark Green Economy report to be released later this year.

Uganda

- The area of land under organic agriculture has risen from 185,000 hectares in 2004 to close to 300,000 hectares in 2008, with a 360 per cent rise in the number of farmers engaged in the sector - from 45,000 certified farmers to 207,000.

- Certified organic exports have risen from US$3.7 million in 2003-2004 to US$22.8 million in 2007-2008.

- The country is also contributing to combating climate change. C02 emissions per hectare are up to 68 per cent less than on conventionally farmed land, with studies indicating that organic fields sequester 3-8 tonnes more carbon per hectare.

China

- More than 10 per cent of Chinese households rely on the sun to heat their water, with more than 40 million solar water heating systems in place.

- The renewable energy sector as a whole generates output worth US$17 billion and employs 1 million workers, of which 600,000 are employed in solar thermal panel making and installing products, such as solar water heaters.

- The warm water from solar water heaters is also reducing rheumatoid arthritis among women as they now have hot water for laundry and dishwashing done by hand instead of only cold water.

Brazil

- The city of Curitiba has, through sustainable urban planning and transport, cut per capita loss from severe congestion. It is about 6.7 and 11 times less than per capita losses in Rio de Janeiro and Sao Paulo.

- In 2002, Curitiba's annual fuel losses from severe traffic congestion equaled R$1.98 million (US$930,000). On per capita terms, this loss is about 13 times and 4.3 times less than those in Sao Paulo and Rio de Janeiro.

- Curitiba's fuel usage is also 30 per cent lower than in Brazil's other major cities.

Other Highlights of the UNEP GC/GMEF

The Intergovernmental Panel on Climate Change (IPCC)

The delegates were addressed by Dr. Rajendra Pachauri, chair of the IPCC which is co- hosted by UNEP and the World Meteorological Organization.

Ministers re-affirmed the central importance of the IPCC and the importance of sound science upon which to base a response to climate change.

However, as a result of recent criticism of the IPCC and some key errors in the body's fourth assessment report, several governments called for an independent review of the IPCC.

Full details of the review and its scope will be announced next week with the report to be presented to the IPCC Plenary taking place in the Republic of Korea in October.

Several key decisions were adopted, including ones on oceans put forward by the Government of Indonesia and the strengthening the environment via the Environmental Management Group which UNEP hosts.

Intergovernmental Platform on Biodiversity and Ecosystem Services (IPBES)

Many experts believe a science panel or platform for biodiversity and ecosystems is needed to assist governments in combating the erosion of plants and animals and ecosystems such as forests, freshwaters and soils.

Governments agreed to a final meeting in June 2010, halfway through the UN's International Year of Biodiversity, to decide whether to establish such a body.

Haiti

Delegates also backed UNEP's support to Haiti in the wake of the devastating earthquake of 12 January 2010 and called on the organization to assist the UN country team to incorporate environmental issues in the rehabilitation and reconstruction and restoration phases.

Gaza

Delegates asked UNEP to assist in implementing recommendations from its environmental assessment of the Gaza Strip compiled following the escalation of hostilities in December 2008 through to January 2009.

The assessment covers issues such as solid waste management, pollution and the acute decline of Gaza's underground water supplies.

Ice shelves disappearing on Antarctic peninsula

2010-02-24T21:49:00.001+05:30

Ice shelves are retreating in the southern section of the Antarctic Peninsula due to climate change. This could result in glacier retreat and sea-level rise if warming continues, threatening coastal communities and low-lying islands worldwide.

Research by the U.S. Geological Survey is the first to document that every ice front in the southern part of the Antarctic Peninsula has been retreating overall from 1947 to 2009, with the most dramatic changes occurring since 1990. The USGS previously documented that the majority of ice fronts on the entire Peninsula have also retreated during the late 20th century and into the early 21st century.

The ice shelves are attached to the continent and already floating, holding in place the Antarctic ice sheet that covers about 98 percent of the Antarctic continent. As the ice shelves break off, it is easier for outlet glaciers and ice streams from the ice sheet to flow into the sea. The transition of that ice from land to the ocean is what raises sea level.

“This research is part of a larger ongoing USGS project that is for the first time studying the entire Antarctic coastline in detail, and this is important because the Antarctic ice sheet contains 91 percent of Earth’s glacier ice,” said USGS scientist Jane Ferrigno. “The loss of ice shelves is evidence of the effects of global warming. We need to be alert and continually understand and observe how our climate system is changing.”

The Peninsula is one of Antarctica’s most rapidly changing areas because it is farthest away from the South Pole, and its ice shelf loss may be a forecast of changes in other parts of Antarctica and the world if warming continues.

Retreat along the southern part of the Peninsula is of particular interest because that area has the Peninsula’s coolest temperatures, demonstrating that global warming is affecting the entire length of the Peninsula.

The Antarctic Peninsula’s southern section as described in this study contains five major ice shelves: Wilkins, George VI, Bach, Stange and the southern portion of Larsen Ice Shelf. The ice lost since 1998 from the Wilkins Ice Shelf alone totals more than 4,000 square kilometers, an area larger than the state of Rhode Island.

The USGS is working collaboratively on this project with the British Antarctic Survey, with the assistance of the Scott Polar Research Institute and Germany’s Bundesamt fur Kartographie und Geodäsie. The research is also part of the USGS Glacier Studies Project, which is monitoring and describing glacier extent and change over the whole planet using satellite imagery.

University of Oklahoma geologists look for answers in Antarctica

2010-02-24T21:05:00.000+05:30

Focusing on a controversial hypothesis that ice existed at the equator some 300 million years ago during the late Paleozoic Period, two University of Oklahoma researchers originated a project in search of clues to the Earth’s climate system.

“The Paleozoic Period was a rare time in history,” says Gerilyn Soreghan, OU professor of geology. “Broadly speaking, it was the last time our planet experienced the type of climate system we have today and in the recent past.” Soreghan believes comparing more modern systems in a range of different climates might help support her hypothesis.

Soreghan and Elwood Madden, assistant professor of geochemistry, want to search for answers in four distinct environments: the cold-dry environment found in Antarctica, the cold-wet environment found in Norway, the hot-wet environment found in Puerto Rico and the hot-dry environment found in the Mojave Desert.

A National Science Foundation project proposal was submitted and the NSF responded with its own proposal recommending a pilot project to the most extreme location proposed – Antarctica. Soreghan was surprised and excited by the NSF proposal. She then began preparing for the journey of a lifetime.

The OU team flew to New Zealand at the end of December and promptly went to the clothing distribution center to be outfitted for the trip. Even though Soreghan and two graduate students would arrive in Antarctica during the summer season, the extremely cold weather proved challenging.

The trip to McMurdo Sound, Antarctica, took roughly 5 hours. Upon arrival, the team met with experienced University of Maine researcher Brenda Hall, who helped the team get ready for the next few weeks. They needed food, radios, tents and other essential equipment for the expedition.

They pinpointed the glaciers where they would take water and sediment samples. When they were ready, a helicopter dropped them in the Dry Valleys and they began collecting samples in one of the smallest rivers in Wright Valley.

Summer in Antarctica was colder and drier than usual and the task of collecting samples downstream was more difficult than expected. The research team would go back on another day to collect additional samples.

The team moved to the Onyx River, the largest river in the valley. Sampling here was more successful as the river flows roughly six weeks during the summer. The water samples taken from the river showed non-random patterns – a good sign, according to Soreghan.

The team took samples at the proximal or closest location to find out what is happening where erosion begins. Glacial systems are typically dominated by physical weathering, a process where the glacier glides across bedrock and grinds it up to create lots of surface area for water to interact with it.

However, many glaciers in Antarctica are frozen to their beds, such that physical grinding is much less important than in temperate glacial systems. Chemical weathering predominates over physical weathering in warmer climates.

During analyses, researchers will examine the chemistry of the sediments and water to determine if there might be certain “markers” or indicators unique to erosion in this type of climate. An electron scanning microscope will allow them to see what kind of physical erosion is going on. Glacial striations or grooves indicate grinding or patterns of grinding.

Analyzing the samples will take about year, but preliminary samples taken from the Wichita Mountains in Oklahoma can be compared with the Antarctic samples to see if there are similarities.

More Americans ‘dismissive’ and fewer ‘alarmed’ about global warming

2010-02-23T23:30:00.008+05:30

Researchers at Yale and George Mason Universities have identified six distinct “Americas” when it comes to the issue of global warming. One of these groups, the “Dismissive,” who believe global warming is not happening and is probably a hoax, has more than doubled in size since 2008 and now represent 16 per cent of the American public, according to the report, Global Warming’s Six Americas, January 2010.

Meanwhile, the per centage of the “Alarmed”—Americans who are the most convinced that global warming is happening, is caused by humans and is a serious and urgent threat—has dropped from 18 per cent in 2008 to 10 per cent.

“Gloomy unemployment numbers, public frustration with Washington, attacks on climate science and mobilized opposition to national climate legislation represent a ‘perfect storm’ of events that have diminished public concerns about global warming—even among the Alarmed,” said Anthony Leiserowitz, director of the Yale Project on Climate Change and a co-author of the report.

Shifts also occurred among the four other groups:

The “Concerned”—Americans who believe global warming is a serious problem and support an active national response, but are less personally involved—have dropped to 29 per cent of the public, down from 33 per cent in 2008.

The “Cautious”—who believe global warming is a problem but not an urgent one, and are unsure whether it is human caused—increased to 27 per cent, from 19 per cent in 2008.

The “Disengaged”—Americans who do not know much about global warming or whether it is happening, and have not thought much about it—decreased to 6 per cent, down from 12 per cent in 2008.

The “Doubtful”—who are not sure whether global warming is happening and believe that, if it is, it is natural and a distant threat—increased slightly to 13 per cent, from 11 per cent in 2008.

Surprisingly, majorities in all six groups say that developing sources of clean energy should be a priority for President Obama and Congress. They also strongly support more funding for research into renewable energy sources and tax rebates for people who buy energy-efficient vehicles or solar panels.

Regulating carbon dioxide as a pollutant, which is currently being considered by the Environmental Protection Agency, is supported by almost all of the groups, including 91 per cent of the Alarmed, 93 per cent of the Concerned, 79 per cent of the Cautious, 92 per cent of the Disengaged and 52 per cent of the Doubtful. Only the Dismissive oppose regulation of carbon dioxide, with only 15 per cent supporting the policy.

“The fact that five of the six Americas support regulating carbon dioxide as a pollutant is bound to be of interest to the president, Congress, and the EPA,” said Edward Maibach, director of the Center for Climate Change Communication at George Mason University. “Some business groups and other special interests are opposing EPA regulation, but most of the American people appear to be for it.”

The results come from a nationally representative survey of 1,001 American adults, age 18 and older. The sample was weighted to correspond with U.S. Census Bureau parameters. The margin of sampling error is plus or minus 3 per cent, with 95 per cent confidence. The survey was designed by researchers at Yale and George Mason Universities and conducted from December 24, 2009 to January 3, 2010 by Knowledge Networks, using an online research panel of American adults.

A copy of the report is available at http://environment.yale.edu/climate.

New insights into helping marine species cope with climate change

2010-02-21T20:47:00.002+05:30

Move, adapt or die. Those are the options marine plants and animals have in the face of climate change, said Stanford biologist Steve Palumbi, who has been exploring how to help them go with the first two options, rather than the third. He's come up with some surprising answers.

Palumbi will be discussing the results of his research in two talks at the annual meeting of the American Association for the Advancement of Science in San Diego.

How to design marine protected areas to best benefit a wide variety of plant and animal species is the focus of a talk he'll give on Saturday, Feb. 20. The most practical kind of natural reserve is one that benefits species and local human populations, but Palumbi said striking that balance isn't always easy. Many people have argued that bigger is better when it comes to marine reserves, but Palumbi has data suggesting that is not always the case.

In a separate Topical Lecture he'll give on Sunday, Feb. 21, Palumbi will present his findings on how marine species are reacting to climate change, including new work on coral species in the Pacific that have poor powers of dispersal but a surprising ability to cope with higher temperatures.

Palumbi is director of Stanford's Hopkins Marine Station and a senior fellow at the university's Woods Institute for the Environment.

If you can't move, then you'd better adjust

Many species, such as those along the west coast of California, can simply migrate north to colder waters. But other animals, such as the coral that Palumbi's team has studied in Fiji and American Samoa, won't be moving anytime soon.

"Each coral population is trapped on its own island, and as global climate changes around them, the populations are essentially stuck where they are. They have to go to the second stage, which is to adapt," Palumbi said.

Marine scientists have predicted that coral reefs will be at risk of extinction due to high ocean temperatures caused by climate change, but Palumbi has found a species of coral that may have a better chance of adapting.

Palumbi's team studied corals growing in shallow lagoons that face intense heat during noontime summer low tides. The team knew these corals were resistant to brief heating but were surprised to find that the corals survived five to six days of high water temperatures. Baking in the tropical summer sun at low tide for 4 to 6 hours a day seems to have better prepared these corals for global warming temperatures.

"When we tested these corals against high temperatures for extended periods of time, they showed all the evidence of having higher resilience," Palumbi said. "It looks like the corals have adapted or acclimated to that stress and have a better chance of resisting high global warming temperatures." How long this resilience will last, and whether all corals can do this, are remaining questions.

Does size matter for marine reserves?

A major response to climate change is to protect reefs from other human-caused stresses such as overfishing. And as a result, a large number of Marine Protected Areas have been implemented in the Pacific. Some are the size of a football field. Some are the size of California. Is bigger better?

To determine how much difference the size of a protected area might make, Palumbi analyzed data from a set of small reserves in Fiji, from the Phoenix Islands and from the Papahanaumokuakea Reserve in Hawaii, the largest marine reserve in the world. All three areas are set aside by government agencies.

The Papahanaumokuakea Marine National Monument covers 360,000 square kilometers (139,000 square miles) in Northwest Hawaii and is a "no-take" reserve, which means nothing may be removed, including fish.

The Phoenix Islands Protected Area, which lies in the central Pacific Ocean between Hawaii and Fiji, is over 408,000 square kilometers (158,000 square miles). There are seven no-take reserves in this area, each about 39 kilometers (24 miles) across.

However, in densely populated areas, smaller reserves are more common. Fiji has 246 such protected areas, each averaging about 2 to 3 square kilometers (about a square mile).

"Small sets of marine protected areas are much more convenient: People can fish in between them or go around them easily. Species found within the marine protected areas easily spill out into the surrounding areas, potentially increasing fishing productivity," Palumbi said.

However, wide stretches of protected ocean allow species to spread more easily than small areas, where they risk being caught by fishermen between the reserves. Therefore, small reserves must be well matched to the plants and animals they are protecting because each species spreads at different rates, Palumbi said.

"Species have lots of different dispersal abilities, so it's very hard to have a marine protected area network that works equally well for all different species. You have to tailor the network of reserves to the species," he said.

Though small reserves meet the needs of fewer species than those of larger reserves, setting aside enormous areas of ocean is not that simple. Scientists and policymakers must consider local residents who depend on fisheries for their well-being.

"With heavy human populations, the political, social and economic problems of a big marine protected area are paramount and you've got to go to another strategy. But it's a strategy with limitations because it's hard to design an area perfectly for all species that need protection," Palumbi said. The most effective reserve is one that balances preservation of species with human needs, he said. Finding that balance is the challenge.

Global warming may hurt some poor populations

2010-02-21T18:23:00.001+05:30

The impact of global warming on food prices and hunger could be large over the next 20 years, according to a new Stanford University study. Researchers say that higher temperatures could significantly reduce yields of wheat, rice and maize – dietary staples for tens of millions of poor people who subsist on less than USD1 a day. The resulting crop shortages would likely cause food prices to rise and drive many into poverty.

But even as some people are hurt, others would be helped out of poverty, says Stanford agricultural scientist David Lobell.

"Poverty impacts depend not only on food prices but also on the earnings of the poor," said Lobell, a center fellow at Stanford's Program on Food Security and the Environment (FSE). "Most projections assume that if prices go up, the amount of poverty in the world also will go up, because poor people spend a lot of their money on food. But poor people are pretty diverse. There are those who farm their own land and would actually benefit from higher crop prices, and there are rural wage laborers and people that live in cities who definitely will be hurt."

Lobell and his colleagues recently conducted the first in-depth study showing how different climate change scenarios could affect incomes of farmers and laborers in developing countries. He will present the results on Feb. 20 at the annual meeting of the American Association for the Advancement of Science in San Diego.

Household incomes

In the study, Lobell, former FSE researcher Marshall Burke and Purdue University agricultural economist Thomas Hertel focused on 15 developing countries in Asia, Africa and Latin America. Hertel has developed a global trade model that closely tracks the consumption and production of rice, wheat and maize on a country-by-country basis. The model was used to project the effects of climate change on agriculture within 20 years and the resulting impact on prices and poverty.
Using a range of global warming forecasts, the researchers were able to project three different crop-yield scenarios by 2030:

"Low-yield" – crop production is toward the low end of expectations.
"Most likely" – projected yields are consistent with expectations.
"High-yield" – production is higher than expected.

"One of the limitations of previous forecasts is that they don't consider the full range of uncertainties – that is, the chance that things could be better or worse than we expect," Lobell said. "We provided Tom those three scenarios of what climate change could mean for agricultural productivity. Then he used the trade model to project how each scenario would affect prices and poverty over the next 20 years.
"The impacts we're talking about are mainly driven by warmer temperatures, which dry up the soil, speed up crop development and shut down biological processes, like photosynthesis, that plants rely on," he added. "Plants in general don't like it hotter, and in many climate forecasts, the temperatures projected for 2030 would be outside the range that crops prefer."

Results

The study revealed a surprising mix of winners and losers depending on the projected global temperature. The "most likely" scenario projected by the International Panel on Climate Change is that global temperatures will rise 1.8 degrees Fahrenheit (1 degree Celsius) by 2030. In that scenario, the trade model projected relatively little change in crop yields, food prices and poverty rates.
But under the "low-yield" scenario, in which temperatures increase by 2.7 F (1.5 C), the model projects a 10 to 20 percent drop in agricultural productivity, which results in a 10 to 60 percent rise in the price of rice, wheat and maize. Because of these higher prices, the overall poverty rate in the 15 countries surveyed was expected to rise by 3 percent.

However, an analysis of individual countries revealed a far more complicated picture. In 11 of the 15 countries, poor people who owned their own land and raised their own crops actually benefitted from higher food prices, according to the model. In Thailand, for example, the poverty rate for people in the non-agricultural sector was projected to rise 5 percent, while the rate for self-employed farmers dropped more than 30 percent – in part because, as food supplies dwindled, the global demand for higher-priced crops increased.

"If prices go up and you're tied to international markets, you could be lifted out of poverty quite considerably," Lobell explained. "But there are a lot of countries, like Bangladesh, where poor people are either in urban areas or in rural areas but don't own their own land. Countries like that could be hurt quite a lot. Then there are semi-arid countries – like Zambia, Mozambique and Malawi – where even if prices go up and people own land, productivity will go down so much that it can't make up for those price increases. In the 'low-yield' scenario, those countries would see higher poverty rates across all sectors."

Under the "high-yield" scenario, in which global temperatures rise just 0.9 F (0.5 C), crop productivity increased. The resulting food surplus led to a 16 percent drop in prices, which could be detrimental to farm owners. In Thailand, the poverty rate among self-employed farmers was projected to rise 60 percent, while those in the non-agriculture sector saw a slight drop in poverty. In Zambia, Mozambique, Malawi and Uganda, poverty in the non-farming sector was projected to decline as much as 5 percent.

Risk management

Lobell said that, although the likelihood of the "low-yield" or "high-yield" scenario occurring is only 5 percent, it is important for policymakers to consider the full range of possibilities if they want to help countries adapt to climate change and ultimately prevent an increase in poverty and hunger.
"It's like any sort of risk management or insurance program," he said. "You have to have some idea of the probability of events that have a big consequence. It's also important to keep in mind that any change, no matter how extreme, will benefit some households and hurt others."