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Saturday, December 18, 2010

Abrupt Climate Change

Abrupt Climate Change
From the Ocean and Climate Change Institute of Woods Hole Oceanographic Institution. This is by far the best and most comprehensive site on the Gulf Stream Shutdown and abrupt climate change
- Are We on the Brink of a New "Little Ice Age"?
- Ocean Monitoring Systems
- Should We Be Worried?
Current Velocities of the Gulf Stream
Department of Earth Observation and Space Systems (DEOS) - Technical University Delft
Quickwatch
Monitoring indicators of abrupt climate change, including the Gulf Stream flow - From UnknownCountry.com


Articles

Apocalypse Now
How Mankind is Sleepwalking to the End of the Earth
Arctic Ice Melting Faster than Predicted
From The Telegraph
A Current Controversy: Is Europe About to Freeze?
From Science Daily
Big Chill, The
Transcript of excellent BBC program on likely effects of a Gulf Stream Shutdown
Currents of Change
Investigating the ocean's role in climate
Great Gulfstream Flip-Flop, The
By William Calvin from the Atlantic Monthly
Gulf Stream
Wikipedia
History of the Gulf Stream
By Jerry Wilkinson
How Global Warming May Cause the Next Ice Age
By Thom Hartmann
How Will Stocks Handle the Big Chill?
From MSN Money
Migrate to New Zealand for Survival?
From Emigrate New Zealand
Ocean Circulation Shut Down by Melting Glaciers after Last Ice Age
From NASA
Ocean Forces Threaten Our Climate
From FirstScience.com
Pentagon Abrupt Climate Change Study
- Global Business Network comments with link to PDF file
Reckoning, The
Global warming is likely to cause huge climatic changes -- and possibly a new Ice Age
Shutdown of Circulation Pattern Could Be Disastrous
From Science Daily
Thermohaline Circulation
From the National Oceanic and Atmospheric Administration (NOAA)
Will Marine Currents Change?
From Manicore.com
Younger Dryas
Wikipedia

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Coldest winter in 1000 years on its way

Coldest winter in 1000 years on its way

Canada Free Press - ‎Dec 16, 2010‎
The change is reportedly connected with the speed of the Gulf Stream, which has shrunk in half in just the last couple of years. Polish scientists say that ...

Friday, December 17, 2010

Seismic stress said moving toward LA




disclaimer: image is for illustration purposes only
http://www.terradaily.com/reports/Seismic_stress_said_moving_toward_LA_999.html Los Angeles (UPI) Dec 17, 2010 Scientists say a 7.2 magnitude Easter earthquake south of the U.S.-Mexico border shifted fault stress to Southern California, creating risks of a temblor there. The findings are a result of a new radar imaging system created by NASA that can detect how land moves after earthquakes and has been scanning the California landscape since 2009, the Los Angeles Times reported Friday.
Comparing old maps with new images after the April 4 Easter Sunday quake, scientists could see where the earth moved and how earthquake tension shifted northward toward Los Angeles.
The radar system found the quake and its aftershocks triggered movement on at least six faults that run close to heavily populated areas in eastern Los Angeles County and the Inland Empire, researchers say.
"There's a number of activities at the southern parts of these long, dangerous faults that indicate there is a changing stress environment," geophysicist Jay Parker, acting chief of the imaging program, said.
"And because these faults are considered hazardous and potentially may have an earthquake that breaks along their length, this brings the whole picture of activity closer to the Los Angeles area."
One of those faults, the Elsinore fault, could generate a magnitude 7 earthquake if its entire length were to rupture in a single event, "which would be bad news for Los Angeles," Eric Fielding, a geophysicist at NASA's Jet Propulsion Laboratory, said.
The pattern of the northward advance of seismic stress may have triggered the 5.4 magnitude earthquake of July 7 south of Palm Springs, Calif., which was felt as far away as Los Angeles, scientists say.
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Thursday, December 16, 2010

Unstable Antarctica: What's driving ice loss?

Unstable Antarctica: What's driving ice loss?

December 16, 2010 by Kathryn Hansen Unstable Antarctica: What's driving ice loss?Enlarge
When surface winds are strong, they stir the Southern Ocean and lift the warm water (red) onto the continental shelf where the additional heat contributes to melt of the ice shelf. Credit: Frank Ippolito
Scientists have previously shown that West Antarctica is losing ice, but how that ice is lost remained unclear. Now, using data from Earth observing satellites and airborne science missions, scientists are closing in on ice loss culprits above and below the ice.
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Why Japan Keeps Whaling

Why Japan Keeps Whaling

Every year, Japanese whaling provokes international outrage, resulting in huge damage to the country’s image. So why does it keep doing it?
Related Features
‘It’s Gojira versus the whalers,’ the headline screamed. Welcome to the latest instalment of the whale wars, where truth has long been a casualty.
As Japan’s whaling fleet set sail this week for its latest expedition to the Southern Ocean, anti-whaling militants Sea Shepherd Conservation Society had already struck a propaganda blow by naming their interceptor vessel after the feared icon of their enemy. While the Japanese movie monster better known as Godzilla has fought many battles throughout his career, it’s fair to say that his creators would never have envisaged him combating his own country’s whalers.
‘This vessel is going to play a huge part in shutting down the Japanese whaling fleet for the entire summer,’Sea Shepherd’s Jeff Hansen told reporters in Fremantle, Australia, where it was registered with the backing of the city’s mayor. The group launched from Hobart its largest ever contingent of three vessels and a helicopter against the Japanese whaling fleet, which in 2009/10 comprised a factory ship, three harpoon ships, a supply ship and http://the-diplomat.com/2010/12/10/the-real-reason-japan-keeps-whaling/?utm_source=The+Diplomat+List&utm_campaign=ea5a9f7eae-Diplomat_Brief_2010_vol25&utm_medium=email

 

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Wednesday, December 15, 2010

Unstable Antarctica: What's Driving Ice Loss by Kathryn Hansen




West Antarctica is seeing dramatic ice loss particularly the Antarctic Peninsula and Pine Island regions. Ice loss culprits include the loss off buttressing ice shelves, wind, and a sub-shelf channel that allows warm water to intrude below the ice. Credit: NASA/NSIDC. For a larger version of this image please go here.
http://www.spacemart.com/reports/Unstable_Antarctica_What_Driving_Ice_Loss_999.html Greenebelt MD (SPX) Dec 16, 2010 Scientists have previously shown that West Antarctica is losing ice, but how that ice is lost remained unclear. Now, using data from Earth observing satellites and airborne science missions, scientists are closing in on ice loss culprits above and below the ice. The findings, presented Dec. 15 at the fall meeting of the American Geophysical Union (AGU) in San Francisco, Calif., are expected to improve predictions of sea level rise.
Time Not Healing Glacial Wounds A new analysis by Ted Scambos, a glaciologist at the National Snow and Ice Data Center in Boulder Colo., and colleagues found that more than a decade after two major Antarctic ice shelves collapsed, glaciers once buttressed by the shelves continue to lose ice.
Changes are most evident in the West Antarctic Ice Sheet and along the Antarctic Peninsula. A spine of mountains forces passing winds to give up their moisture as snow, feeding glaciers that in turn feed the ice shelves that jut out into the Southern Ocean. More than a decade ago, dramatic changes started affecting a series of ice shelves, collectively called Larsen, along the Peninsula's northeast coast.
In 1995, Larsen A was the first to collapse followed by a larger loss of Larsen B in 2002. Today, a small piece of the Larsen B and the entirety of the vast Larsen C hang on.
Investigating how the glaciers have responded to the loss of these ice shelf "dams," Scambos and colleagues tracked elevation information using data from satellites such as NASA's Ice, Cloud and land Elevation Satellite (ICESat) and previous airborne missions. They show that between 2001 and 2006, glaciers feeding Larsen A and Larsen B lost 12 gigatons of ice loss per year, or 30 percent of all ice lost throughout the Peninsula.
Moreover, the continued draw down of glaciers, such as Drygalski Glacier, fifteen years after the loss of Larsen A, have set precedent for what to expect elsewhere. Losses by glaciers that fed the Larsen B, such as Crane Glacier, are likely to continue.
Scambos and a team of colleagues have now placed instruments on glaciers just south of the area where the shelves disintegrated, anticipating that further warming will lead to further glacier speed-ups. The instruments and new aircraft overflights will provide further insight into shelf break-up and the onset of ice acceleration. Wind Matters
Further south is West Antarctica's Pine Island Glacier, another site of major ice loss presently draining more than 19 cubic miles of ice per year from the West Antarctic Ice Sheet. It continues to deteriorate rapidly and scientists want to know why.
By combining satellite and airborne data, Bob Bindschadler, a glaciologist with the Goddard Earth Sciences and Technology Center at NASA's Goddard Space Flight Center in Greenbelt, Md., has successfully gained more insight into interactions between the atmosphere, ocean and ice even though the data can't reveal these connections directly.
Bindschadler and colleagues looked at images from the Landsat satellite and spotted a series of large surface undulations on the ice shelf. Next they matched the undulations with the timing of warm water pulses in the waters adjacent to the ice shelf. When surface winds are strong, they stir the Southern Ocean and lift the warm water onto the continental shelf where the additional heat contributes to melt.
Airborne data showed the ice shelf was up to 150 meters (492 feet) thinner when the warmer water was present, allowing Bindschadler's team to establish a direct link between the rate of ice shelf melting and atmospheric wind speed. When the team accounted for the heat coming in and the ice lost, they concluded that only 22 percent of the heat is used in melting.
Whether the remaining heat might melt additional ice is unknown, but it is clear that the atmospheric circulation has a strong role on the future of the ice shelf and the fate of the ice sheet inland. Stronger winds would lead to an acceleration of ice loss; weaker winds would have a stabilizing effect.
"In short, ice shelves are affected by what winds are doing," Bindschadler said. "As Antarctic Circumpolar winds continue to increase, ice shelves are at increasing risk."
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EU's 'mackerel war' with Iceland heats up




http://www.terradaily.com/reports/EUs_mackerel_war_with_Iceland_heats_up_999.html Brussels (AFP) Dec 14, 2010 The European Union could block Iceland's fishing boats from unloading mackerel in European ports unless a fishing row is resolved, a source close to the European Commission said Tuesday. EU Maritime Affairs Commissioner Maria Damanaki told the 27-nation bloc's fisheries ministers she wanted to invoke the European Economic Area agreement to bar Iceland from unloading the fish in EU ports, the source said.
Damanaki has instructed her services to start working on an "ad hoc" regulation that would prohibit landings of fish stocks on a raw or processed form when an international sharing arrangement has not been found.
Negotiations between Iceland, Norway and the European Union failed this year.
Iceland, which has applied to join the EU, unilaterally raiseed its mackerel catch quota to 130,000 tonnes this year compared to 2,000 tonnes in previous years, a move that angered Brussels.
The nordic island condemned a decision by the EU and Norway to give themselves a quota of nearly 584,000 tonnes for 2011 in the absence of an agreement.
Iceland's negotiator, Tomas Heidar, has warned that this represented more than 90 percent of the allowable catch recommended by scientists.
"If the EU and Norway do not reconsider their decision, they will bear the responsibility of overfishing from the stock next year," he said in a statement.
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Hot With Decades Of Drought: Expectations For The Southwest




A core extracted from a living Douglas-fir tree in the Santa Rita Mountains south of Tucson, Ariz. Scientists use such cores to study the annual rings of trees, visible on the core as banding. Collecting such cores causes only temporary injury to the tree. Credit: Copyright 2009 Daniel Griffin
http://www.terradaily.com/reports/Hot_With_Decades_Of_Drought_Expectations_For_The_Southwest_999.html Tempe AZ (SPX) Dec 15, 2010 An unprecedented combination of heat plus decades of drought could be in store for the Southwest sometime this century, suggests new research from a University of Arizona-led team. To come to this conclusion, the team reviewed previous studies that document the region's past temperatures and droughts.
"Major 20th century droughts pale in comparison to droughts documented in paleoclimatic records over the past two millennia," the researchers wrote. During the Medieval period, elevated temperatures coincided with lengthy and widespread droughts.
By figuring out when and for how long drought and warm temperatures coincided in the past, the team identified plausible worst-case scenarios for the future. Such scenarios can help water and other resource managers plan for the future, the team wrote.
"We're not saying future droughts will be worse than what we see in the paleo record, but we are saying they could be as bad," said lead author Connie A. Woodhouse, a UA associate professor of geography and regional development. "However, the effects of such a worst-case drought, were it to recur in the future, would be greatly intensified by even warmer temperatures."
The team's paper is part of the special feature, "Climate Change and Water in Southwestern North America," scheduled for publication Dec. 13 in the Early Online edition of the Proceedings of the National Academy of Sciences.
The paper by Woodhouse and her colleagues is titled, "A 1,200-year perspective of 21st century drought in the southwestern North America." Co-authors are Glen M. MacDonald of the University of California, Los Angeles; Dave W. Stahle of the University of Arkansas in Fayetteville; and Edward R. Cook of Lamont-Doherty Earth Observatory of Columbia University, Palisades, N.Y.
The analysis in the current paper includes previous research by Woodhouse, co-author David M. Meko and others that documented past droughts that lasted several decades. Moreover, some of those droughts occurred during times of relatively warm temperatures.
Within the last 2,000 years, there have been several periods of severe and sustained drought that affected much of western North America.
Droughts that are accompanied by warm temperatures have more severe impacts on ecosystems, said Meko, an associate research professor in the UA's Laboratory of Tree-Ring Research.
During the Medieval period, temperatures were about 1.8 degrees Fahrenheit (1 C) above the long-term average. Average temperatures in the Southwest have been warmer than that since 1990 and are projected to increase at least another 3.6 F (2 C) by 2100, Woodhouse said.
The most severe warm-climate drought in the Southwest within the last 1,200 years was 60 years long and occurred during the mid-12th century, according to research by Meko and others. That drought covered most of the western U.S. and northern Mexico.
For a 25-year period during that drought, Colorado River flow averaged 15 percent below normal, according to the tree-ring-based reconstruction of stream flow at Lees Ferry.
For every 1.8 degree Fahrenheit (1 C) of warming in the future, Colorado River flow is projected to decrease between two and eight percent, Woodhouse and her co-authors wrote.
The Colorado River supplies water for cities and agriculture in seven western states in the U.S. and two states in northwestern Mexico. Los Angeles, Las Vegas, Denver, Phoenix, Tucson and Albuquerque are among the many cities dependent on Colorado River water.
"Even without warming, if you had one of those medieval droughts now, the impact would be devastating," she said. "Our water systems are not built to sustain us through that length of drought."
Noting that the Colorado River flows recorded at Lees Ferry from 2000 to 2009 are the lowest on record, Woodhouse said the current drought could be part of a longer dry period. The instrumental record from Lees Ferry goes back to 1906.
"As this drought unfolds you can't really evaluate it until you're looking back in time," she said.
In recent decades, temperatures have been higher than during the previous 1,200 years, and future temperatures are predicted to be even warmer, Woodhouse said.
In addition, other research predicts that changes in atmospheric circulation will reduce the amount of winter precipitation the Southwest receives in the future, she said.
"The bottom line is, we could have a Medieval-style drought with even warmer temperatures," Woodhouse said.
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Clouds Likely Created Positive Climate Feedback In Past Decade The climate effect from clouds is hard to understand and predict because clouds can change rapidly and are difficult to both measure and model with high accuracy. by Patrick Lynch

http://www.terradaily.com/reports/Clouds_Likely_Created_Positive_Climate_Feedback_In_Past_Decade_999.html
College Station TX (SPX) Dec 15, 2010 A Texas A and M scientist's study of 10 years of NASA and other data found that clouds likely responded to carbon dioxide-induced global warming by amplifying that warming. This amplified response is what scientists call a "positive feedback." The uncertainty about the feedback clouds will exhibit to increased greenhouse gases and a warmer climate remains one of the most difficult problems in long-term climate prediction.
This new research, to be published Dec. 10 by Andrew Dessler in Science, is the first to look at real-world observations of global clouds at low and high altitudes. And when Dessler did that he found evidence of a positive feedback, and evidence that despite the uncertainty levels, current climate models are doing a reasonable job simulating cloud feedback.
"We've used observations to show that clouds amplify the warming we get from carbon dioxide," Dessler said.
"No one has really rigorously quantified this feedback, and that's basically what I've done. The cloud feedback is indeed positive. It does amplify the warming we get from greenhouse gases. The results suggest that our understanding and the models' simulation is actually quite good."
According to Dessler, clouds still remain too much of an uncertainty for this research to make a robust correlation to projections of long-term cloud feedback. But for the first time on a significant time scale and a global spatial scale, a likely positive feedback from clouds has been observed, and not just seen in model results.
The reason this observation has not been made previously is that it requires both high-resolution data, which wasn't available until more recently, and a long enough data set to observe what is happening with the climate, as opposed to just annual weather fluctuations.
The decade Dessler studied, from 2000 to 2010, ended up being an ideal data set because it included both hot and cool years, compared to the mean, allowing him to observe how clouds responded to different conditions.
The climate effect from clouds is hard to understand and predict because clouds can change rapidly and are difficult to both measure and model with high accuracy.
Low altitude clouds composed of water droplets (i.e., not ice) typically reflect solar radiation and cool the atmosphere, while high altitude, icy, cirrus clouds typically trap outgoing infrared radiation and creating additional warming.
Dessler found about an 80 percent likelihood that from 2000 to 2010 the global cloud cover created a positive feedback - which means that on the whole clouds created an additional warming effect on the planet.
Dessler studied data from NASA's Clouds and the Earth's Radiant Energy System (CERES) satellite mission and NASA's Modern Era Retrospective-analysis for Research and Application (MERRA) data set, as well as from the European Center for Medium-Range Weather Forecasting's interim re-analysis.
In technical terms, Dessler found that for every 1 degree (C) of warming, clouds amplify that by trapping an additional 0.5 Watts per square meter - the standard for measuring incoming and outgoing energy in Earth's atmosphere. Dessler noted that the decade did not see an obvious enough temperature trend to say what fraction of any warming clouds were responsible for.
Michael Bosilovich, of NASA's Goddard Space Flight Center's Global Modeling and Assimilation Office (GMAO), in Greenbelt, Md., which oversees the MERRA project, said the cloud analysis is a good example of the benefit of continued satellite observations and long-term
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Tuesday, December 14, 2010

Sea level rise a 'challenging issue' that needs to be addressed: scientists

http://www.physorg.com/news/2010-12-sea-issue-scientists.html

December 14, 2010 By Tim Stephens Sea level rise a 'challenging issue' that needs to be addressedEnlarge

Flooding of low-lying areas on the Central Coast occurred during the 1983 El Niño winter, including downtown Capitola (above) and Corcoran Lagoon (below). With sea level rise, such events will occur with greater frequency and magnitude. Photos courtesy of Gary Griggs.



Sea level is rising, and California's coastal communities will need to prepare for the gradual inundation of low-lying areas, as well as increased erosion rates and damage from storms. Gary Griggs, professor of Earth and planetary sciences at the University of California, Santa Cruz, is working on a guidebook for local government agencies to help them make the difficult the decisions ahead.


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Have We Really Solved the Mystery Behind the Shocking Die-off of Bees?

Have We Really Solved the Mystery Behind the Shocking Die-off of Bees?
The New York Times essentially called it 'case closed' on Colony Collapse Disorder, but there is good reason to be wary about their reporting. READ MORE
By Tom Laskawy / Grist.org

Earthshaking Possibilities May Limit Underground Storage Of CO2


Earthshaking Possibilities May Limit Underground Storage Of CO2

The problem with potential earthquakes arises, Zoback said, because the interior of the continent is crisscrossed by ancient faults that are often poised to fail - what he calls "a state of failure equilibrium" - because of the immense tectonic forces acting on them.
by Staff Writers Stanford CA (SPX) Dec 14, 2010

Storing massive amounts of carbon dioxide underground in an effort to combat global warming may not be
easy to do because of the potential for triggering small- to moderate-sized earthquakes, according to 
Stanford geophysicist Mark Zoback. While those earthquakes are unlikely to be big enough to hurt 
people or property, they could still cause serious problems for the reservoirs containing the gas.
"It is not the shaking an earthquake causes at the surface that creates the hazard in this instance, it 

is what it does at depth," Zoback said. "It may not take a very big earthquake to damage the seal of an underground reservoir that has been pumped full of carbon dioxide."
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Earthshaking possibilities may limit underground storage of carbon dioxide


December 13, 2010
Storing massive amounts of carbon dioxide underground in an effort to combat global warming may not be easy to do because of the potential for triggering small- to moderate-sized earthquakes, according to Stanford geophysicist Mark Zoback.
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Scientists predicts continued death of forests in southwestern US due to climate change

http://www.physorg.com/news/2010-12-drought-temperatures-weaken-southwest-forests.html

December 13, 2010
(Santa Barbara, Calif.) –– If current climate projections hold true, the forests of the Southwestern United States face a bleak future, with more severe –– and more frequent –– forest fires, higher tree death rates, more insect infestation, and weaker trees. The findings by university and government scientists are published in this week's issue of the Proceedings of the National Academy of Sciences (PNAS).
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Satellite data provide a new way to monitor groundwater aquifers in agricultural regions

Satellite data provide a new way to monitor groundwater aquifers in agricultural regions

December 13, 2010 Satellite data provide a new way to monitor groundwater aquifers in agricultural regionsEnlarge
More than 100 center-pivot sprinklers, controlled by a central computer, irrigate wheat, alfalfa, potatoes and melons along the Columbia River near Hermiston, Ore.
(PhysOrg.com) -- Stanford researchers have found a way to use satellite data to monitor groundwater aquifers previously obscured by the crops they nourish.

http://www.physorg.com/news/2010-12-satellite-groundwater-aquifers-agricultural-regions.html


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Assessing the environmental effects of tidal turbines

Assessing the environmental effects of tidal turbines

December 13, 2010 Assessing the environmental effects of tidal turbines

UW researchers brave rough conditions in February to lower the monitoring tripod into the water. Credit: University of Washington
Harnessing the power of ocean tides has long been imagined, but countries are only now putting it into practice. A demonstration project planned for Puget Sound will be the first tidal energy project on the west coast of the United States, and the first array of large-scale turbines to feed power from ocean tides into an electrical grid.

http://www.physorg.com/news/2010-12-environmental-effects-tidal-turbines.html


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Astronomers Find First Evidence Of Other Universes by kfc

Piecemeal Energy Policy will still cut Greenhouse Emissions

Piecemeal Energy Policy will still cut Greenhouse Emissions
by Kevin Bullis
But the lack of comprehensive legislation could prevent international agreements needed to limit global warming.
Read More »

Monday, December 13, 2010

US southwest could see 60-year drought: study

US southwest could see 60-year drought: study
Washington (AFP) Dec 13, 2010 -
A worst-case scenario devised by US researchers shows that the American southwest could experience a 60-year stretch of heat and drought unseen since the 12th century. Researchers at the University of Arizona examined studies of temperature changes and droughts in the region over the past 1,200 years and used them to project future climate models in the hope that water resource managers coul ... more
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Decline Of West Coast Fog Brought Higher Coastal Temperatures Last 60 Years

Decline Of West Coast Fog Brought Higher Coastal Temperatures Last 60 Yearshttp://www.terradaily.com/reports/Decline_Of_West_Coast_Fog_Brought_Higher_Coastal_Temperatures_Last_60_Years_999.html
Seattle WA (SPX) Dec 14, 2010 -
Fog is a common feature along the West Coast during the summer, but a University of Washington scientist has found that summertime coastal fog has declined since 1950 while coastal temperatures have increased slightly. Fog formation appears to be controlled by a high-pressure system normally present off the West Coast throughout the summer, said James Johnstone, a postdoctoral researcher w ... more

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Freshwater Sustainability Challenges Shared By Southwest And Southeast

http://www.terradaily.com/reports/Freshwater_Sustainability_Challenges_Shared_By_Southwest_And_Southeast_999.html Athens GA (SPX) Dec 14, 2010 Water scarcity in the western U.S. has long been an issue of concern. Now, a team of researchers studying freshwater sustainability in the U.S. have found that the Southeast, with the exception of Florida, does not have enough water capacity to meet its own needs. Twenty-five years ago, environmentalist Marc Reisner published Cadillac Desert: The American West and Its Disappearing Water, which predicted that water resources in the West would be unable to support the growing demand of cities, agriculture and industry.
A paper co-authored by a University of Georgia researcher and just published in a special issue of the journal Proceedings of the National Academy of Sciences offers new support for most of Reisner's conclusions, using data and methods unavailable to him in 1986.
Although the paper focuses on freshwater sustainability in the Southwest, co-authors Tushar Sinha, a postdoctoral scientist at North Carolina State University; John Kominoski, a postdoctoral associate at the UGA Odum School of Ecology; and William Graf, a professor of geography at the University of South Carolina, said that the findings have important implications for the Southeast as well. "It turns out that the Southeast has a relatively low capacity for water storage," said Graf.
In order for water supply to be considered sustainable, the researchers calculated that no more than 40 percent of freshwater resources can be appropriated for human use, to ensure that streamflow variability, navigation, recreation and ecosystem use are accommodated.
They also determined how much water a region would need to meet all its municipal, agricultural and industrial needs-its virtual water footprint. The VWF includes the water needed if a region were to grow enough food to support its own population.
The researchers found that neither the Southwest nor the Southeast have enough water capacity to meet all their own needs; both these regions virtually import water from other parts of the country, in the form of food. "The Southeast has virtually no positive, inland VWFs," said Kominoski, who earned his doctoral degree from the Odum School.
"The largest population centers in southeastern states, with the exception of Florida, are inland. Piedmont cities such as Atlanta, Charlotte and Birmingham rely on small watersheds, which may be why our VWFs are negative."
Study lead author John Sabo, associate professor at Arizona State University, added that the Southeast's municipal and industrial water demands are higher than supported by locally generated streamflow.
Reisner also predicted the loss of reservoir capacity. The researchers found that both eastern and western reservoirs have lost storage capacity to sedimentation, although not at the rate predicted by Reisner. "The good news is that the minimum life span of most of the dams in the Southeast is greater than two centuries, which is much longer than what Reisner anticipated," said Graf.
The researchers also found that reservoirs lose enormous amounts of water to evaporation each year, resulting in a drop in reliable water yield. "The Eastern U.S. has a higher density of reservoirs, but similar water losses as the West," Graf said, adding that although there are more reservoirs in the East, they are smaller than their Western counterparts. The researchers found that smaller reservoirs are more susceptible to evaporation losses than larger ones are.
Sinha added that most of these smaller reservoirs in the Southeast are designed to capture precipitation that falls within a year, as opposed to larger western reservoirs which carry water surplus or deficit over multiple years.
Furthermore, changes in precipitation in the Southeast rapidly influence reservoir water levels. "The recent droughts in the Southeast during the summers of 2002, 2005 and 2007 clearly indicate severe water shortages due to very low rainfall, and water supply is dependent upon precipitation, which is likely to be more uncertain in the near future," said Sinha.
Loss of storage capacity and lack of enough water to support human needs is not the only freshwater sustainability issue in the Southeast. "The fragmentation of river networks threatens the level of aquatic biodiversity of the Southeast, which is the highest in North America, in terms of both native and non-native species," Kominoski said. "Our current system doesn't support the needs of people, let alone ecosystems."
The authors also cautioned that the paper's estimates are conservative. "The data we used is from 1950-99," Sinha said. "The last decade, which had some of the highest recorded temperatures and most extreme droughts, as well as higher population figures, was not included. Also, the estimates don't take climate change into account. We expect to have less precipitation in the summer, during the growing season, and more severe droughts."
Kominoski agreed, and added that the 2000 Census predicts continuing population growth in the sunbelt. "As population grows, so does demand for water," he said.
The paper's conclusion that the Southwest is near its limit in terms of water capacity holds true for the Southeast as well. "We need a new strategy for water storage and conservation in the U.S., including the Southeast," said Kominoski. "Because we have mostly inland metropolitan areas in small watersheds, we need to use less water. Less water comes to us, and our ability to store water is challenged by our climate and geographic location."
Graf added that demand for water is already an issue of major disagreement among Southeastern states. "We hope that these findings and recommendations will inform the debate and help lead to workable solutions," he said.

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Global Eruption Rocks The Sun Locations of key events are labeled in this extreme ultraviolet image of the sun, obtained by the Solar Dynamics Observatory during the Great Eruption of August 1st. White lines trace the sun's magnetic field. Credit: K Schrijver and A. Title. by Dr. Tony Phillips Science@NASA

http://www.spacedaily.com/reports/Global_Eruption_Rocks_The_Sun_999.html
Huntsville AL (SPX) Dec 14, 2010 On August 1, 2010, an entire hemisphere of the sun erupted. Filaments of magnetism snapped and exploded, shock waves raced across the stellar surface, billion-ton clouds of hot gas billowed into space. Astronomers knew they had witnessed something big. It was so big, it may have shattered old ideas about solar activity.
"The August 1st event really opened our eyes," says Karel Schrijver of Lockheed Martin's Solar and Astrophysics Lab in Palo Alto, CA. "We see that solar storms can be global events, playing out on scales we scarcely imagined before."
For the past three months, Schrijver has been working with fellow Lockheed-Martin solar physicist Alan Title to understand what happened during the "Great Eruption."
They had plenty of data: The event was recorded in unprecedented detail by NASA's Solar Dynamics Observatory and twin STEREO spacecraft. With several colleagues present to offer commentary, they outlined their findings at a press conference at the American Geophysical Union meeting in San Francisco.
Explosions on the sun are not localized or isolated events, they announced. Instead, solar activity is interconnected by magnetism over breathtaking distances. Solar flares, tsunamis, coronal mass ejections--they can go off all at once, hundreds of thousands of miles apart, in a dizzyingly-complex concert of mayhem.
"To predict eruptions we can no longer focus on the magnetic fields of isolated active regions," says Title, "we have to know the surface magnetic field of practically the entire sun."
This revelation increases the work load for space weather forecasters, but it also increases the potential accuracy of their forecasts.
"The whole-sun approach could lead to breakthroughs in predicting solar activity," commented Rodney Viereck of NOAA's Space Weather Prediction Center in Boulder, CO. "This in turn would provide improved forecasts to our customers such as electric power grid operators and commercial airlines, who could take action to protect their systems and ensure the safety of passengers and crew."
In a paper they prepared for the Journal of Geophysical Research (JGR), Schrijver and Title broke down the Great Eruption into more than a dozen significant shock waves, flares, filament eruptions, and CMEs spanning 180 degrees of solar longitude and 28 hours of time. At first it seemed to be a cacophony of disorder until they plotted the events on a map of the sun's magnetic field.
Title describes the Eureka! moment: "We saw that all the events of substantial coronal activity were connected by a wide-ranging system of separatrices, separators, and quasi-separatrix layers." A "separatrix" is a magnetic fault zone where small changes in surrounding plasma currents can set off big electromagnetic storms.
Researchers have long suspected this kind of magnetic connection was possible. "The notion of 'sympathetic' flares goes back at least three quarters of a century," they wrote in their JGR paper. Sometimes observers would see flares going off one after another--like popcorn--but it was impossible to prove a link between them. Arguments in favor of cause and effect were statistical and often full of doubt.
"For this kind of work, SDO and STEREO are game-changers," says Lika Guhathakurta, NASA's Living with a Star Program Scientist. "Together, the three spacecraft monitor 97% of the sun, allowing researchers to see connections that they could only guess at in the past."
To wit, barely two-thirds of the August event was visible from Earth, yet all of it could be seen by the SDO-STEREO fleet. Moreover, SDO's measurements of the sun's magnetic field revealed direct connections between the various components of the Great Eruption-no statistics required.
Much remains to be done. "We're still sorting out cause and effect," says Schrijver. "Was the event one big chain reaction, in which one eruption triggered another--bang, bang, bang--in sequence? Or did everything go off together as a consequence of some greater change in the sun's global magnetic field?"
Further analysis may yet reveal the underlying trigger; for now, the team is still wrapping their minds around the global character of solar activity. One commentator recalled the old adage of three blind men describing an elephant--one by feeling the trunk, one by holding the tail, and another by sniffing a toenail. Studying the sun one sunspot at a time may be just as limiting.
"Not all eruptions are going to be global," notes Guhathakurta. "But the global character of solar activity can no longer be ignored."
As if the sun wasn't big enough already....
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