e360 digest
Climate
02 Nov 2012:
Sea-Level Rise Projections
Ignored Critical Feedbacks, Researcher Says
A U.S. researcher says projected sea-level rise over the next century has been underestimated because current models
fail to consider several critical feedbacks that might accelerate rising seas in the coming decades. While the 2007 report of the Intergovernmental Panel on Climate Change predicted that global sea levels could rise 0.2 to 0.5 meters by 2100, current projections suggest that seas could rise a meter or more. One of the factors ignored by earlier models, says University of Colorado geologist Bill Hay, is the influx of warm, briny ocean water into the Arctic that occurs when melting fresh water is released, a phenomenon he says acts as a sort of “heat pump” in the Arctic, adding more ice-free waters, which then absorb more solar energy. According to Hay, who will present his findings at the annual meeting of The Geological Society of America, another factor that was ignored is the potential melting of large ice sheets in Greenland and western Antarctica. A third feedback, he said, is the vast amounts of groundwater being removed to address humankind’s surging water needs, much of which ultimately ends up in the oceans.
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01 Nov 2012:
Timelapse of Hurricane Sandy
Shows Birth and Death of Historic Storm
As the storm that was Hurricane Sandy weakened over Pennsylvania, NASA released
a timelapse animation of the lifespan of the massive storm, tracking its path from

NASA
the Caribbean, where it developed, to its violent landfall on the mid-Atlantic coast of the U.S. The collection of images, taken by the NASA GOES-13 satellite from Oct. 23 to Oct. 31, illustrates the storm gaining intensity as it traveled north, at times reaching nearly 1,000 miles in width. When the storm reached the mid-Atlantic on Oct. 29, it became wedged between a cold front over the Appalachian Mountains and a high-pressure air mass over maritime Canada, preventing it from moving north or east and instead driving it ashore. At that point Sandy became a Nor’easter, triggering historic storm surges in coastal areas of New York and New Jersey and blizzard conditions in the mountain regions. Meteorologists say the swath of high winds produced by Sandy while it was a hurricane
covered nearly 2 million square miles.
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Photo Gallery: A Quest to Document
The Earth’s Disappearing Glaciers
Since 2007, photographer James Balog has deployed dozens of time-lapse cameras on four continents to chronicle one of the starkest examples of global warming — the rapid melting of the world’s glaciers. That project, known as the Extreme Ice Survey and carried out in collaboration with leading glaciologists, is captured in an
e360 gallery of his photos selected from his new book,
Ice: Portraits of Vanishing Glaciers. In an accompanying
interview with Yale Environment 360, Balog discusses what has driven him to devote so much of his life to “preserving the visual memory” of a vanishing landscape. “We’re telling a story about what’s happening right here, right now, as a consequence of human action,” he says. “I think it’s vital to keep telling that story.”
View a photo gallery
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In New York, The Rising Threat Of
Flooding Was Predicted for Years
While climate experts hesitate to say Hurricane Sandy was caused by climate change, scientists for years have predicted that such devastating events would become increasingly common as sea levels rise and ocean
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MOMA
Rising Currents: A 2010 exhibit showed visions of New York adapting to climate change.
temperatures become warmer. For more than a decade, reports have warned that climate change will likely trigger more intense hurricanes and more frequent and
severe flooding in low-lying areas, such as occurred in New York and New Jersey. And with sea levels projected to rise by as much as six inches per decade by mid-century and
as much as several feet by 2100, experts say
New York City’s flood zone will continue to expand. In Sandy's wake,
New York officials are starting to discuss projects that might withstand such surges, including building a levee system or barriers.
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30 Oct 2012:
Vulnerability of Infrastructure
Revealed During Hurricane Sandy
The storm that crippled the New York City region has revealed the extreme
vulnerability of its transportation and electricity infrastructure and highlights the need to better protect subways, tunnels, low-lying roads, and power substations as sea levels rise
View gallery

Andrew Burton/Getty Images
Flooding in New York City’s Financial District
and storms produce higher seawater surges in the future. New York City and the surrounding area experienced
unprecedented damage to its transportation infrastructure, with the subway system knocked out for an estimated four to five days, several major tunnels flooded, regional rail lines crippled, and highways and roads underwater. Gov. Andrew Cuomo said Tuesday morning that the city and the state may have to
consider building a levee to protect lower Manhattan, where waters rose 10 feet above flood stage. Other experts suggested that other significant steps will have to be taken to protect New York City, including building sea gates that would keep surging storm waters out of New York Harbor. Climate scientists said that the impact of hurricanes can be expected
to become more severe as temperatures increase and sea levels rise by an estimated three to six feet this century.
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25 Oct 2012:
Rapid Thinning of Glaciers
Seen After Collapse of Antarctic Ice Shelf
NASA has released satellite photos that
vividly depict the precipitous thinning and retreat of two Antarctic glaciers following the disintegration of the Larsen B Ice Shelf. That ice shelf — which floated on top of the
Weddell Sea and once was the size of Connecticut — collapsed in 2002 after several years of warm summer temperatures. The Larsen B had acted as a buttress slowing the flow of numerous glaciers into the sea. The NASA satellite images, taken in 2002 and in 2012, demonsrate how swiftly the Green and Hektoria glaciers behind the ice shelf surged into the ocean. The 2002 photo shows the glaciers covering much of nearby mountain ridges and the termini, or end points, of the glaciers are not visible. The 2012 photo shows that the thinning glaciers now cover considerably less of surrounding mountain ridges and the termini of both glaciers are visible. The 2012 image also shows the numerous crevasses that have formed as the glaciers have thinned.
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22 Oct 2012:
Shifting Arctic Wind Patterns
May Cause Increased Melt, Study Says
U.S. scientists say unusual air pressure patterns over the Arctic during the month of June in recent years have altered wind patterns in the region, funneling warmer air into the Arctic and contributing to record low Arctic
View images

NOAA
Air pressure over the Arctic, 2007-2012.
summer sea ice extent from 2007 to 2012. Writing
in the journal Geophysical Research Letters, a team of researchers illustrated how the formation of two unusual high pressure areas over the North American Arctic and Greenland disrupted the normal westerly flow of winds, creating “blocking highs” that led to an unusually strong flow of warm southerly air.
That sent more warm air into the central Arctic and Greenland, which may have been a factor in unusually dramatic summer thaws beginning in 2007. While it is unclear why these unusual patterns of high pressure have occurred in each of the last six Junes, NOAA researcher James Overland believes it may be related to declining snow cover in the Canadian Arctic in recent years. “We don’t know that part of the story yet,” he said.
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Solar Geoengineering Projects
Could Be More Effective on Regional Scale
A new modeling study by several geoengineering experts suggests that injecting aerosols into the atmosphere to block more of the sun’s energy and reduce temperatures could be
most effective when done on a region-by-region basis. The study, published in the journal
Nature Climate Change, said that injecting aerosols over the Arctic Ocean in summer, for example, might be an effective way to not only slow the rapid loss of Arctic sea ice but possibly even restore it to pre-industrial levels. The researchers — led by David Keith of Harvard University, Ken Caldeira of the Carnegie Institution for Science, and Douglas McMartin of the California Institute of Technology — cautioned that their models were rough and that bringing about changes in regional climate patterns
can have global effects. But they said the study shows the need for more detailed research into how solar geoengineering techniques could be used to slow or reverse the effects of climate change on rapidly warming areas. “Our research goes a step beyond the one-size-fits-all approach to explore how careful tailoring of solar geoengineering can reduce possible inequalities and risks,” said Keith.
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19 Oct 2012:
Increased Ocean Acidification
May Alter The Acoustics of Seawater
Increased ocean acidification over the next century
could alter the acoustic properties of seawater, giving the planet’s oceans the same hi-fi sound they had during the age of the dinosaurs. In an analysis of ocean acidity over 300 million years, U.S. researchers David G. Browning and Peter M. Scheifele calculated that increased ocean acidity as a result of global warming will have a negative effect on the absorption of low-frequency sounds. By 2100, they predict, sounds near the oceans surface, such as whale songs or sounds created by ships, will travel perhaps twice as far as they do today. The scientists based their calculations on historic levels of boron in seafloor sediments and an analysis of its sound-absorption traits and impacts on low-frequency transmission. “[This knowledge] impacts the design and performance prediction of sonar systems,” said Browning, who
will present the findings at the annual meeting of the Acoustical Society of America. “It affects estimation of low frequency ambient noise levels in the ocean. And it's something we have to consider to improve our understanding of the sound environment of marine mammals and the effects of human activity on that environment."
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16 Oct 2012:
Increasingly Severe Droughts
Could Transform U.S. Forests, Study Says
Severe drought conditions in the southwestern U.S. in recent years could become normal in the years to come, a shift that
could trigger increased tree mortality and ultimately transform the region’s forests, a new study says. In an analysis of tree-ring data from conifer trees dating back to A.D. 1000, a team of scientists concluded that while the region endured several “mega-droughts” over the last 1,000 years, the long-term drought that began in the late-1990s could end up being the worst yet and may portend even drier periods in the future. After modeling the level of stress caused by droughts on forests — and considering other factors caused by these changes, including bark-beetle outbreaks and wildfires — the researchers calculated that tree mortality over the next four decades will be worse than at any time over the last 1,000 years. “With increasing drought stress, our forests of tomorrow will hardly resemble our forests of yesterday,” said Henri Grissino-Mayer, a geography professor at the University of Tennessee, Knoxville and one of the authors of the study
published in the journal Nature Climate Change.
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15 Oct 2012:
‘Rogue’ Geoengineering Scheme
In Pacific Violated UN Rules, Groups Say
A project sponsored by a controversial U.S. businessman dumped about 100 tons of iron sulphate into the Pacific Ocean this summer, an experiment in geoengineering that environmental groups say violated international agreements,
The Guardian has reported. According to the report, satellite images appear to confirm that the iron dumped from a fishing boat sponsored by Russ George, the former CEO of Plankton Inc., triggered a nearly 10,000-squre-kilometer plankton bloom off Canada’s west coast. Some researchers believe this technique could emerge as a critical strategy in reducing the effects of climate change since such blooms are capable of sucking carbon out of the atmosphere and ultimately trapping it deep in the ocean. The experiment took place west of the islands of Haida Gwaii, where George convinced the council of an indigenous village to approve the project. Critics say it should not have taken place without proper scientific assessment and violated existing UN resolutions. Scientists say it is unclear whether such iron fertilization damages ocean ecosystems, triggers toxic tides, or worsens the effects of ocean acidification.
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11 Oct 2012:
Norway Proposes CO2 Tax Hike
To Increase Climate Mitigation Funds
Norway has announced plans to
nearly double its carbon tax on the nation’s offshore petroleum sector to create a £1 billion fund to help combat the effects of climate change, including in developing nations. In a draft budget released this week, government officials proposed a climate program that would increase the tax on oil companies from about £24 per ton of carbon dioxide to £45 (Nkr410) per ton. The plan would allocate about £1 billion (Nkr10 billion) to promote green energy initiatives, reduce carbon emissions, and improve food security in developing countries. In addition, Norway would pledge about £44 million to help developing nations preserve tropical forests, which play a critical role in storing carbon. Norway has previously helped fund efforts to reduce deforestation in Brazil, Indonesia, and Ethiopia. These new plans come as the oil-rich nation looks to expand its oil exploration into the Barents Sea between Norway and Russia.
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11 Oct 2012:
Group Calls for Swift Growth
Of Carbon Capture-and-Storage Facilities
An industrial group says that to avoid “dangerous climate change” an additional 55 facilities that capture carbon from power plants and store it underground
must be built by 2020. The group, the Global CCS Institute, said that only one new carbon-capture-and-storage (CCS) plant was built in the past year, bringing the current number to 75. The institute acknowledged that the goal of building 130 CCS plants by 2020 was unlikely, but argued that the technology is a
proven method of reducing carbon dioxide emissions and vital to future strategies to slow global warming. The institute said that just eight of the 75 plants now in operation have achieved a greater reduction in CO2 emissions that all other greenhouse gas reduction efforts instituted in the UK and Australia. CCS Institute President Brad Page said that governments should treat CCS technology as they do other low-carbon initiatives, like solar and wind power, which often receive subsidies and other government aid designed to encourage the growth of renewable energy.
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10 Oct 2012:
Software Maps CO2 Emissions
Down to Building and Street Levels
A team of U.S. researchers has developed a software system that they say documents carbon dioxide emissions in urban areas
down to the level of individual buildings or street segments. Using publicly available
Click to enlarge

Bedrich Benes and Michel Abdul-Massih
Annual carbon emissions, Indianapolis
data on local pollution, traffic counts, and building uses — as well as models of building-by-building energy consumption — the researchers from Arizona State and Purdue universities were able to create three-dimensional maps detailing carbon emissions. The researchers hope the software will provide insights into urban CO2 sources and help guide public policy on climate change and sustainable energy use. “Cities have had little information with which to guide reductions in greenhouse gas emissions — and you can’t reduce what you can’t measure,” said Kevin Gurney, an assistant professor at Arizona State University. So far, the so-called Hestia software has been used to produce visualizations for the city of Indianapolis, but the group is also developing maps for Los Angeles and Phoenix.
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08 Oct 2012:
Indonesian Palm Oil Is
Growing Source of CO2 Emissions
The rapid expansion of palm oil plantations in the world’s tropical regions, particularly Indonesian Borneo, is becoming
an increasingly significant source of global carbon emissions, a new study says. Writing
in the journal Nature Climate Change, researchers from Stanford and Yale universities project that the continued expansion of plantations will add more than 558 million metric tons of carbon dioxide into the atmosphere by 2020 — an amount greater than all of Canada’s current fossil fuel emissions. Much of the expansion in recent decades has occurred in Indonesia, particularly on the island of Borneo, also known as Kalimantan. According to researchers, the loss of forest for palm oil plantations in Kalimantan led to the emission of more than 140 million metric tons of CO2 in 2010 alone, or the equivalent of the annual emissions of 28 million vehicles. About 80 percent of planting leases remained undeveloped in 2010, the study says. If all these leases are developed, more than one-third of Kalimantan’s lowlands outside of protected areas would be covered with palm oil plantations.
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03 Oct 2012:
Major Policy Shifts Needed
To Maintain Decline in U.S. CO2 Emissions
A decline in U.S. carbon emissions in recent years
is unlikely to continue over the long term unless there is a significant shift in how the nation produces and uses its energy, according to a new analysis. While several factors have triggered a 9 percent decline in annual carbon emissions in the U.S. since 2005 — including a decrease in the use of coal-fired electricity as a result of the natural gas boom — the most significant factor has been the economic recession, according to the group Climate Central. As the economy recovers, any reductions in greenhouse gas emissions will likely be offset by increased incomes that drive an greater demand for vehicles, electrical appliances, and other consumer products.
The report calculates that U.S. carbon emissions can be reduced 38 percent below 2005 levels by 2035 if several hypothetical changes occur. These include the number of miles driven remaining at today’s level and average vehicles achieving fuel efficiency of 55 miles-per-gallon; significant gains being made in the efficiency of energy-consuming equipment; and natural gas continuing to reduce the share of coal-burning technologies.
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03 Oct 2012:
NASA Map Illustrates
Effects of Drought on U.S. Vegetation
A new NASA map shows the
major effects of this summer’s record droughts on vegetation across much of the U.S., leaving a swath of parched earth that caused a shortage of food for wild and domesticated animals alike. In the map, which shows the contrast between
plant health during August and the average conditions for the month from 2002 to 2012, a vast brown area from the Rocky Mountains to the Ohio River valley illustrates regions where plant growth was below normal. The map is based on satellite data fed into the so-called Normalized Difference Vegetation Index, which measures the extent to which plant leaves absorb visible light and reflect infrared light. Drought-impacted vegetation reflects more light than healthy vegetation. “I am struck by the extraordinary depth and spatial scale of this drought,” said Molly Brown, a vegetation and food security researcher with NASA. “There is very little fodder out there for animals to eat.” Almost two-thirds of the contiguous U.S. experienced some level of drought by the end of August, with 39 percent of the nation enduring severe to extreme drought, according to the U.S. Drought Monitor.
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27 Sep 2012:
High-Arctic Summers
Are Warmer than Any Time in 1,800 years
Summer temperatures on the Norwegian archipelago of Svalbard in the High Arctic
are now higher than during any time over the last 1,800 years, including a period of higher temperatures in the northern hemisphere known as the
Medieval Warm Period, according to a new study. In an analysis of algae buried in deep lake sediments, a team of scientists calculated that summer temperatures in Svalbard since 1987 have been 2 to 2.5 degrees Celsius (3.6 to 4.5 degrees F) warmer than during the Medieval Warm Period, which lasted from roughly 950 to 1250 AD. The Medieval Warm Period is often cited by climate change skeptics as proof that the planet has experienced periods of high temperatures in recent centuries unrelated to the burning of fossil fuels. The algae, which make more unsaturated fats in colder periods and more saturated fats in warmer periods, reveal critical clues about past climates. Scientists were able to date the lake specimens by analyzing grains of glass emitted by a series of well-known Icelandic volcanoes that left unique chemical time markers. The study is published in the journal
Geology.
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25 Sep 2012:
Coral Biodiversity Hotspot
Is Found in Western Indian Ocean
The western Indian Ocean, especially the waters between Madagascar and Africa, contain
one of the highest levels of coral diversity worldwide, with 369 coral species identified in a recent study and more still to be identified. Scientists say the western Indian Ocean may contain as much coral biodiversity as Australia’s Great Barrier Reef, though not as much as the world’s richest region for corals, the so-called coral triangle in Southeast Asia.
Reporting in the journal PLoS ONE, David Obura, a scientist with the Group Coastal Oceans Research and Development in the Indian Ocean, said that 10 percent of the species are found only in the western Indian Ocean. He said the northern end of the Mozambique Channel, between Madagascar and mainland Africa, contains roughly 250 to 300 coral species. Meanwhile, Australian scientists report that water temperatures around the Great Barrier Reef
have increased steadily in the last 25 years, in some places rising as much as .5 degrees C. Such increases can contribute to coral bleaching, which can lead to mass coral die-offs.
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24 Sep 2012:
Majority of Undecideds Say
Global Warming Important in U.S. Election
The majority of undecided voters in the U.S. presidential race say that the candidates’ views on global warming will be an important factor in determining how they vote,
according to a new poll. While very few participants called global warming their single-most important issue, about 61 percent of undecided voters say it will be one of several important issues that influence their decision. Probable voters for President Obama were far more likely to consider global warming important (75 percent) than likely Mitt Romney voters (32 percent), according to the poll, which was conducted by the Yale Project on Climate Change Communication and the George Mason University Center for Climate Change Communication. From two-thirds to three-quarters of undecided and likely Obama voters also said they believe the president and Congress should be “doing more” about global warming. Only about a third of likely Romney voters said the president or Congress should be doing more.
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20 Sep 2012:
Arctic Sea Ice Extent
Reaches a Dramatic New Low
As the summer melt season ends, Arctic sea ice extent
has now fallen to an exceptionally low level, covering an area only half the size of the 1979 to 2000 average. The
Colorado-based National Snow and Ice Data Center (NSIDC) reported that as of September 16, Arctic sea ice extent was only 1.32 million square miles, which is 18 percent below the previous record low of 1.61 million square miles, set in September 2007. “We are now in uncharted territory,” said NSIDC director Mark Serreze. “While we’ve long known that as the planet warms up, changes would be seen first and be most pronounced in the Arctic, few of us were prepared for how rapidly the changes would actually occur.” A key reason for the precipitous decline of sea ice extent is that Arctic Ocean ice has become so thin after years of rapidly rising temperatures in the region, with thick, multi-year ice being replaced by thin, year-old ice that swiftly melts in summer.
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17 Sep 2012:
Most Coral Reefs At Risk
Even if Warming Limited to 2 Degrees C
Most of the world’s coral reefs will likely be subject to long-term degradation
even if global warming is limited to 2 degrees Celsius, and as much as one-third of coral reef systems will likely be vulnerable to threats even under the most optimistic climate projections, a new study says. In an analysis of the potential effects of heat stress on coral reef systems under different climate change scenarios, a team of researchers found that most potential outcomes will likely trigger more frequent and intense mass-bleaching events. If global mean temperature increases exceed 2 degrees C, coral reefs “might no longer be prominent coastal ecosystems,” said Katja Frieler, a researcher at the Potsdam Institute for Climate Impact Research and lead author of the study,
published in Nature Climate Change. Under the most optimistic scenarios — including aggressive climate mitigation and assumptions that coral systems can adapt to warming conditions — one third of the world’s coral systems would still be subject to severe degradation, the study said.
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13 Sep 2012:
In Himalaya Mountains,
A Mixed Picture of Glacial Melting
A new study says that glaciers in the Himalayas are
reacting to climate change in different ways, with glaciers in the eastern and central Himalayas retreating at accelerating rates, while glaciers in the western Himalaya and Hindu Kush region are more stable and possibly even growing in places. According to
a report by the National Research Council, many of the glaciers of the Himalayan region are retreating at rates comparable to other parts of the world, but changes to glacial meltwater are not likely to make a significant difference in water availability at lower elevations, which rely more on monsoon rains and snowmelt. If the the current rate of glacial retreat continues, however, the report said that high-elevation areas of some river basins could see altered seasonal water flow. In addition, researchers say the melting of glaciers could affect regional water security during periods of drought or “similar climate extremes.” The Himalaya/Hindu Kush region is the source of several river systems — including the Indus, Ganges, and Brahmaputra — that supply drinking water and irrigation to 1.5 billion people.
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06 Sep 2012:
Destruction of Tropical Forests
Reduces Regional Rainfall, Study Says
A new study has found that destruction of the world’s tropical forests
may significantly reduce regional rainfall across large regions, a phenomenon researchers say could have devastating effects for people living in and around the Amazon and Congo basins. Using satellite observations of rainfall and vegetation, as well as atmospheric wind flow patterns, researchers from the University of Leeds and the NERC Center for Ecology & Hydrology found that across 60 percent of the Amazon and Congo rainforests, air passing over extensive forest areas produces twice as much rain as air passing over areas with little vegetation. According to their findings,
published in the journal Nature, this effect in some cases can increase rainfall thousands of miles away. After combining these findings with projected deforestation rates and current trends, the researchers calculated that tropical forest loss could reduce rainfall across the Amazon basin during the wet season by 12 percent by 2050, and 21 percent during the dry season.
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30 Aug 2012:
Brazilian Deforestation
Falls Sharply in Past Eight Years
Deforestation in the Brazilian Amazon fell by 77 percent from 2004 to 2011, but
carbon emissions did not drop as steeply because of complex processes revealed during on-the-ground studies, scientists say. While analysis of satellite images showed the three-quarters drop in deforestation, researchers said that several factors — including the slow decay of roots and the later burning of wood biomass — meant that carbon emissions from deforestation fell by 57 percent during the same period, according to a study published in the journal
Global Change Biology. Another reason for the 20-percent lag in carbon emissions reductions is that logging in recent years has been moving into denser Amazon forests, so even the reduced amount of deforestation is leading to higher carbon emissions, researchers said. U.S. scientists praised their Brazilian colleagues for the sophisticated new techniques used to tease out the differences between reduced deforestation and lagging emissions reductions. “That’s where you’d like the rest of the world to be, where Brazil is,” said Richard Houghton of the Woods Hole Research Center.
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28 Aug 2012:
Arctic Ice Reaches Record Low
The extent of ice covering the Arctic Ocean has reached
a new record low and will likely continue to retreat until mid-September, when re-freezing begins to occur, according to satellite observations. NASA and the
U.S.-funded National Snow and Ice Data Center (NSIDC) reported that sea ice extent fell in the past few days to 1.58 million square miles (4.1 million square kilometers), breaking by 27,000 square miles the previous record low extent, set in September 2007. Summer sea ice extent has declined by more than 40 percent since satellites began tracking it in 1979, and sea ice now
covers less than 30 percent of the Arctic Ocean. Sea ice experts say that both the extent and thickness of Arctic summer sea ice has declined so precipitously in the face of rapidly rising temperatures that the Arctic basin appears to be heading for largely ice-free summers within a decade or two. “Parts of the Arctic have become like a giant slushy,” said Walt Meier, a research scientist at the NSIDC. The disappearing sea ice is creating ever-larger areas of dark, heat-absorbing waters, which is further increasing temperatures in the Arctic and hastening the melting of Greenland’s massive ice sheets.
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21 Aug 2012:
NASA Image Shows Low Waters
Of Drought-Stricken Mississippi River
A pair of NASA satellite images
comparing water flow along the Mississippi River this month with August 2011 illustrates the effects of a severe summer drought along the critical waterway. The recent photo, taken just south
of Memphis, Tennessee on Aug. 8, reveals extensive sandbars that are newly exposed or far larger than they were a year ago. Numerous stretches of the river have become significantly narrowed by decreased water flow. The drought, the worst in 56 years,
has left the Mississippi River at its lowest levels since 1988, with some areas more than 12 feet lower than normal conditions at this time of year. Ninety-seven vessels were stranded by low waters near Greenville, Mississippi, where an 11-mile stretch of the river was closed for dredging. Near St. Louis, the U.S. Army Corps of Engineers has been forced to stop river traffic for up to 12 hours at a time in order to keep the shipping lane wide enough, according to Reuters.
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21 Aug 2012:
Cloud Brightening Scheme
Should Be Tested Over Oceans, Scientists Say
An international group of scientists has urged a small-scale experiment
to test the viability of creating human-made clouds as a way to counter the effects of global warming. Writing in the journal
Philosophical Transactions of the Royal Society, the scientists say
John McNeill
there should at least be a scientific debate over the possibilities of so-called cloud brightening, a process that involves sending particles, in this case sea water, into the atmosphere to create clouds that would, theoretically, reflect a greater amount of sunlight back into space. While ethical and political questions remain about such geoengineering schemes, that is no reason to not test the technology, said Rob Wood, a University of Washington physicist and one of the paper’s authors. In the paper, the scientists suggest a small-scale test in which salt water is sprayed from a ship or barge followed by airborne measurements of the physical and chemical characteristics of the resulting clouds.
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13 Aug 2012:
Shifting Climate Makes Frogs
More Vulnerable to Disease, Study Says
Increasingly unpredictable swings in the weather
are making frogs more vulnerable to the deadly chytrid fungus, according to a new study. In a series of tests, scientists at Oakland University in Michigan exposed Cuban treefrogs living under a variety of conditions in laboratory incubators to chytridiomycosis, a highly infectious fungal disease that has
decimated amphibian species globally. The scientists found that frogs that were exposed to unpredictable temperature changes were more susceptible to the disease. For example, frogs that were shifted to incubators at a temperature of 15 degrees C (59 degrees F) after spending four weeks at a temperature of 25 C (77 F)
were far more likely to suffer infections than those frogs already accustomed to living at 15 C. According to Thomas Rafell, an Oakland University researcher and lead author of the study, the fungus was likely able to adapt faster to the temperature shift because it is smaller and has a shorter generation time than its host. The study was
published in the journal Nature Climate Change.
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09 Aug 2012:
New Atmospheric Compound
Tied to Human Health and Climate Change
An international team of researchers says it
has discovered a new atmospheric compound that reacts with sulfur dioxide to form sulfuric acid, which produces acid rain, has negative respiratory effects on humans, and causes increased cloud formation.
Reporting in Nature, the scientists from the U.S., Finland, and Germany identified the new compound as a type of carbonyl oxide, formed by the reaction of ozone with natural and manmade hydrocarbons, known as alkenes. When the carbonyl oxide compounds react with sulfur dioxide — which is primarily produced by coal and other fossil fuel combustion at power plants — large amounts of sulfuric acid are produced. The scientists say it is the first time that this complex new interaction of atmospheric compounds has been documented. Sulfuric acid creates acid rain that is harmful to terrestrial and aquatic life, and airborne sulfuric acid particles play the main role in the formation of clouds, an increase of which could help cool the planet. Smaller sulfuric acid particles near the planet’s surface have been shown to cause human respiratory ailments.
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