The Rocky Reach Dam has straddled the wide, slow Columbia River since the 1950s. It generates enough electricity to supply homes and industries across Washington and Oregon.But the dam in recent years hasn't produced as much power as it might: Its massive turbines act as deadly blender blades to young salmon, and engineers often have had to let the river flow over the spillway to halt the slaughter, wasting the water's energy potential.
The ability of the nation's aging hydroelectric dams to produce energy free of the curse of greenhouse gas emissions and Middle Eastern politics has suddenly made them financially attractive -- thanks to the new economics of climate change. Armed with the possibility of powerful new cap-and-trade financial bonuses, the National Hydropower Assn. has set a goal of doubling the nation's hydropower capacity by 2025.Expanding hydropower is fraught with controversy, much of it stemming from the industry's history of turning wild rivers into industrialized reservoirs struggling to support their remaining fish. The emerging boom in hydroelectric power pits two competing ecological perils against each other: widespread fish extinctions and a warming planet.The issue has been particularly contentious in the Pacific Northwest, where some are calling for actually breaching dams on the Snake River in an effort to bring back the declining salmon and steelhead.
"Hydropower does have pretty significant and serious impacts on rivers. We know that. The industry knows that," said John Seebach, director of the Hydropower Reform Initiative launched by the conservation group American Rivers. "It also provides some pretty significant benefits in terms of power production. So it's a tricky balance to get those benefits while trying to minimize those impacts."Across the country, there are about 82,600 dams, but only about 3% of them are used to generate electricity. Hydropower produces about 6% of the nation's electricity, and nearly 75% of all renewable electric power.The increasing mandates for power utilities to expand their portfolios of renewable energy are prompting dam operators to take a second look at thousands of dams now used for flood control, irrigation, navigation, recreation and industrial water supply that might also be used to generate electricity without further harm to fish."Most of the bang for the buck is at existing dams and reservoirs without hydropower facilities, and hydropower facilities that need to be upgraded for additional capacity," said Norman Bishop, vice president of MWH Americas Inc., which designed the dam improvements in Chelan County, Wash., home to the Rocky Reach facility.The U.S. Department of Energy estimated that there are up to 30,000 megawatts of potential energy at 5,677 undeveloped sites across the nation, more than half of which already have dams.Newly added to the equation is the emerging market for so-called carbon credits. The credits are part of a strategy to place "caps" on damaging greenhouse gas emissions while allowing companies that can't meet the restriction to buy credits from ones that achieve significant savings. The cap would be gradually lowered to reduce overall emission levels.Hydroelectric power is a prime candidate to sell credits because it is largely emission-free. The credits typically would be granted only for new or additional power.The market for the credits is tiny now, but legislation is moving forward that would create caps and a national market that could ultimately reach $120 billion a year.Even without a national cap-and-trade law, markets such as the Chicago Climate Exchange now allow companies to voluntarily limit their carbon emissions and lower their carbon footprint by purchasing credits, traded on the market like stock.This added incentive has made building or upgrading hydroelectric facilities a more alluring prospect.The small rural Chelan County Public Utility District last year became the first hydropower facility in the U.S. to begin trading carbon credits on the Chicago Climate Exchange.The money the district has made from selling credits -- about $1.6 million so far -- is going back to Chelan County and its customers for new investments in carbon-free electricity. The district has invested heavily in making sure its new electricity results have no net harm to salmon -- a key requirement for trading on the Chicago exchange.But the possibility of more hydroelectric construction around the world has set off alarm bells among some groups of environmentalists."Rivers in the U.S. have been seriously impacted by dam construction," the conservation group International Rivers said in urging California authorities to disqualify hydropower projects producing more than 10 megawatts of power from receiving carbon credits."Fortunately, some of this damage is now starting to be reversed by dam removals," the group said. "California climate action should not act as an incentive to increase damage to rivers and prevent efforts to restore them."California gets about 9.6% of its power from large hydro generators. The state has said it will consider as renewable energy only those hydro projects smaller than 30 megawatts that do not require the diversion of any new water.Climate-change activists particularly balk at the idea of offering carbon credits in the U.S. for large hydropower projects in developing countries, such as Chile, Peru, Uganda and elsewhere, where environmental protections may be lax and the overall contribution to global welfare dubious.But here at Rocky Reach Dam, engineers say they believe there is a way to reduce emissions, increase power output and save fish at the same time -- although at a cost.The Chelan County utility district spent $292 million overhauling Rocky Reach's 11 aging generators and installing new, more efficient turbines and an expensive mile-long safe-passage tunnel for up to 3.5 million young salmon and steelhead that navigate the dam each year.With the juvenile-fish passage facilities -- along with commitments to improve habitat and expand hatchery production for salmon -- the district could meet its targets for healthy fish and allow much less water to spill over the dam.Five years ago Rocky Reach had to spill up to a quarter of its water over a 31-day period during the height of the spring salmon juvenile migration, but last spring it got permission to spill no water at all.Yet more than 90% of the young salmon and 94% of the steelhead are surviving their trip past Rocky Reach Dam, according to district records.The result is that the dam has been able to produce an additional 1.75 million more megawatt-hours of electricity over a recent three-year period, the equivalent of 702,204 metric tons of carbon if the electricity were generated at a natural-gas-fired power plant."What we have been able to do is provide more power with the same amount of water," said Tracy Yount, the Chelan County utility district's external affairs director. "We're saying, let's skip the new facilities, skip the regulatory issues associated with new dams and go to our existing facilities and get more value from them."
Monday, July 27, 2009
Combining being gay and green
Gerod Rody didn't mess around with noble sentiments.
When I asked him why he started a green group pitched at the gay community, he said, "I kind of wanted to date and have the parts of my life come together."
But he is serious about both gender identity and environmental sustainability. And as far as he knows, his organization, Out for Sustainability, is the only one that tries to combine being gay with being green.
Rody is regularly drawing people out to social and educational events, sponsored by his and other pro-green organizations. On Earth Day, Out put on two Earth Gay events, doing habitat restoration on Beacon Hill and building a garden in South Park so some kids going through drug recovery can have fresh vegetables.
Rody is a designer and business consult who has a bachelor's degree in European studies from the University of Washington. He lives in West Seattle and just this June finished his master's degree in sustainable business at the Bainbridge Graduate Institute. He's planned weddings and helped design buildings, including helping his mother develop an organic restaurant in Puyallup.
He said his parents helped steer him toward social involvement. His father is a chiropractor and his mother has always been committed to natural living.
"So I kind of grew this early-on sense that you are supposed to be responsible your own self and your community as well."
His faith plays a role, too. Rody was brought up as an evangelical Christian. He's a Presbyterian now, but he's always believed "one of the reasons I was brought into the world is to effect positive change."
There weren't many other gay people at the Bainbridge institute, he said, so he felt "my values, centered on sustainability and my sexuality, were really disconnected."
He looked for organizations that bridge the gap but couldn't find one. So he enlisted fellow student Julian O'Reilley, and she helped him put together an organization (the Web site is outsustainability.com) with help from their network of friends in green groups and the gay community.
The sustainability movement is more than a subculture now, he said, and LGBT (lesbian, gay, bisexual, transgender) people are moving toward the mainstream. It felt like the right time to do some matchmaking.
There is a lot of diversity in the LGBT community. Rody's demographic, gay men, like most of us, has a mixed reputation when it comes to sustainable living.
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Remember "Queer Eye for the Straight Guy"? That image doesn't hold true for everyone, but it's common enough, and a flair for consumption is not green. But living in small spaces in urban areas is.
Even Rody isn't entirely green. "Most of my clothes, I buy used, but I like shoes."
His idea isn't to push for perfection, but "to affirm people in what they already do" and provide them opportunities to learn about other things they can do.
"I've been surprised by how many people say they aren't being sustainable, but they take the bus to work, or they compost."
So far, the project hasn't jump-started his dating life, but Rody said, "It has expanded my social network and added depth to it."
That's nice, but there's something noble here, too: getting more people to embrace sustainable lifestyles.
When I asked him why he started a green group pitched at the gay community, he said, "I kind of wanted to date and have the parts of my life come together."
But he is serious about both gender identity and environmental sustainability. And as far as he knows, his organization, Out for Sustainability, is the only one that tries to combine being gay with being green.
Rody is regularly drawing people out to social and educational events, sponsored by his and other pro-green organizations. On Earth Day, Out put on two Earth Gay events, doing habitat restoration on Beacon Hill and building a garden in South Park so some kids going through drug recovery can have fresh vegetables.
Rody is a designer and business consult who has a bachelor's degree in European studies from the University of Washington. He lives in West Seattle and just this June finished his master's degree in sustainable business at the Bainbridge Graduate Institute. He's planned weddings and helped design buildings, including helping his mother develop an organic restaurant in Puyallup.
He said his parents helped steer him toward social involvement. His father is a chiropractor and his mother has always been committed to natural living.
"So I kind of grew this early-on sense that you are supposed to be responsible your own self and your community as well."
His faith plays a role, too. Rody was brought up as an evangelical Christian. He's a Presbyterian now, but he's always believed "one of the reasons I was brought into the world is to effect positive change."
There weren't many other gay people at the Bainbridge institute, he said, so he felt "my values, centered on sustainability and my sexuality, were really disconnected."
He looked for organizations that bridge the gap but couldn't find one. So he enlisted fellow student Julian O'Reilley, and she helped him put together an organization (the Web site is outsustainability.com) with help from their network of friends in green groups and the gay community.
The sustainability movement is more than a subculture now, he said, and LGBT (lesbian, gay, bisexual, transgender) people are moving toward the mainstream. It felt like the right time to do some matchmaking.
There is a lot of diversity in the LGBT community. Rody's demographic, gay men, like most of us, has a mixed reputation when it comes to sustainable living.
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Remember "Queer Eye for the Straight Guy"? That image doesn't hold true for everyone, but it's common enough, and a flair for consumption is not green. But living in small spaces in urban areas is.
Even Rody isn't entirely green. "Most of my clothes, I buy used, but I like shoes."
His idea isn't to push for perfection, but "to affirm people in what they already do" and provide them opportunities to learn about other things they can do.
"I've been surprised by how many people say they aren't being sustainable, but they take the bus to work, or they compost."
So far, the project hasn't jump-started his dating life, but Rody said, "It has expanded my social network and added depth to it."
That's nice, but there's something noble here, too: getting more people to embrace sustainable lifestyles.
Noise pollution affects birds' nesting habits
A new study has come up with the strongest evidence yet that noise pollution negatively influences the nesting habits of birds.The study also indicates that at least a few species opt for noisy areas over quiet ones, perhaps because of their vocalisation pitches, a reduction in nest predators and less competition from other song birds that prefer quiet environments. The researchers found that 32 bird species nested in quiet areas undisturbed by noise pollution, while 21 species were nesting in noisy areas. The team also found only three bird species nested exclusively at the noisy sites, while 14 species nested only in the quiet sites. The three-year study compared nesting birds inhabiting pinyon-juniper woodland sites surrounding natural gas extraction sites and their noise-producing compressors with birds nesting in adjacent, quieter woodland sites. While bird species richness declined at noisy sites, bird nesting success was higher there than in the nearby quiet sites, said Clinton Francis, University of Colorado at Boulder (CU-B) who led the study. "This is the first study to show that noise pollution causes changes in species interactions within bird communities," said Francis. "Since noise pollution can be a major cause of declining bird diversity in and around urban areas, better noise control using quieter road surfaces and sound-reducing walls should be considered to help preserve such communities." While other studies have shown noise pollution can have a negative impact on bird species, most have been conducted near heavily used roads, said Francis. These findings were published online in Current Biology
Global warming would cause more high tides: Mumbai civic body
The civic body, which was on its toes for the last two days as high tides measuring over 5 metres hit the city's shores, has warned of similar occurence for next two-three years because of global warming and called for steps to stop possible flooding.
We must consider ourselves lucky as there were no heavy rain (along with tides) and hence the effect was not much. But due to global warming more such high tides will hit the city in next two-three years," Municipal commissioner Jairaj Phatak said. We must learn from our sister cities - St Petersburg, Barcelona and New York - who faced similar situation like Mumbai, but have come out with their own solutions, he said. "At St Petersburg, they constructed a dam outside the city limit and also a wall because of which the high tide does not hit the city directly. Though this is not possible for a city like Mumbai, which is surrounded by sea, but we will study what other cities have done and would then think what can be done here," Phatak said. The civic officials had warned of July 26, 2005-like deluge as the city today witnessed a 5.05 metre high tide, but fortunately heavy rains did not coincide with the tide. Brihanmumbai Municipal Corporation (BMC) was geared up for the day and had taken several precautionary measures, like evacuating people from low-lying areas.
We must consider ourselves lucky as there were no heavy rain (along with tides) and hence the effect was not much. But due to global warming more such high tides will hit the city in next two-three years," Municipal commissioner Jairaj Phatak said. We must learn from our sister cities - St Petersburg, Barcelona and New York - who faced similar situation like Mumbai, but have come out with their own solutions, he said. "At St Petersburg, they constructed a dam outside the city limit and also a wall because of which the high tide does not hit the city directly. Though this is not possible for a city like Mumbai, which is surrounded by sea, but we will study what other cities have done and would then think what can be done here," Phatak said. The civic officials had warned of July 26, 2005-like deluge as the city today witnessed a 5.05 metre high tide, but fortunately heavy rains did not coincide with the tide. Brihanmumbai Municipal Corporation (BMC) was geared up for the day and had taken several precautionary measures, like evacuating people from low-lying areas.
Akal Takht tells Sikhs to go green
SULTANPUR LODHI: Akal Takht, the highest Sikh temporal body, has embraced the save-the-environment mantra telling Sikhs across the world it was their "moral and religious duty"to care for the nature.
Akal Takht Jathedar Gurbachan Singh gave a religious call to the community on Sunday saying Sikhs should now focus on cleaning the natural water resources rather than spending more money on building up new gurdwaras. ‘‘Whereever in the world you (Sikhs) may be, your focus should now be on cleaning up of natural water resources rather than building gurdwaras,’’ he said at a function here on the ninth anniversary of cleaning of Kali Bein, a river in Kapurthala district. Environmentalists said the Jathedar has set a precedent with his call for saving the environment from depletion. Many said the call would prompt devotees to do their bit for the environment. Some said the appeal from the Jathedar could make other religious leaders to think about contributing to the environment. It could even help save the most important river in the country, the Ganges river, they added. The Kali Bein, a much polluted river flowing through Sultanpur Lodhi, was cleaned in an initiative by the Akhat Takht Jathedar through community participation.
Akal Takht Jathedar Gurbachan Singh gave a religious call to the community on Sunday saying Sikhs should now focus on cleaning the natural water resources rather than spending more money on building up new gurdwaras. ‘‘Whereever in the world you (Sikhs) may be, your focus should now be on cleaning up of natural water resources rather than building gurdwaras,’’ he said at a function here on the ninth anniversary of cleaning of Kali Bein, a river in Kapurthala district. Environmentalists said the Jathedar has set a precedent with his call for saving the environment from depletion. Many said the call would prompt devotees to do their bit for the environment. Some said the appeal from the Jathedar could make other religious leaders to think about contributing to the environment. It could even help save the most important river in the country, the Ganges river, they added. The Kali Bein, a much polluted river flowing through Sultanpur Lodhi, was cleaned in an initiative by the Akhat Takht Jathedar through community participation.
Chemical in plastic tied to preemie problems
A chemical used in many plastic products and already under scrutiny for potential health risks is suspected of raising the risk of liver problems in premature babies, according to a new study.
The small study in a German hospital suggests a chemical known as a phthalate, used in some intravenous feeding bags and tubing, may raise preemies' chances for liver damage.
Rigorous research on phthalates' effects in humans is lacking, and at least one expert found the German study unconvincing. There is no solid proof implicating the phthalate studied, DEHP.
However, the researchers said their results show that hospitals treating newborns or preemies should turn to IV feeding equipment that doesn't contain DEHP. Some hospitals in the U.S. already have switched.
Premature babies' livers are immature so they are already at risk for liver complications. They also are often fed intravenously, a practice already known to increase liver problems. The new study, published Monday in the journal Pediatrics, says one possible reason is DEHP. Animal studies suggest the phthalate chemical may cause various health risks including liver abnormalities and reproductive system damage.
Also found in toys, vinyl flooringPhthalates (pronounced thowl-ates) are found in many products besides medical supplies — toys, vinyl flooring and cosmetics. They're used to stabilize fragrances and make plastics flexible. Some countries and California have restricted their use.
They are different from bisphenol-A, or BPA, a plastic-hardening chemical that also has raised health concerns and is found in food containers and other products. It's no longer used in many baby bottles.
In a 2002 phthalates advisory, the Food and Drug Administration recommended alternatives for patients most at risk from the chemical leeching out of plastic medical equipment, including sick infant boys because of possible damage to developing reproductive organs.
Liver issues with half preemies exposed to DEHPThe German study involved 30 mostly premature infants treated in a Mannheim intensive care unit before the hospital switched to feeding equipment without the chemical, and 46 infants treated there afterward.
Serious liver problems involving reduced flow of bile, a digestive fluid produced by the liver, developed in 50 percent of the infants fed with the tubes containing DEHP versus just 13 percent of the other infants.
The researchers took into account other factors that might contribute to liver problems, and the two groups were mostly similar. However, the chemical group was intravenously fed for an average of 26 days, four more days than the other infants.
That is a limitation that could have skewed the results. But that alone "wouldn't have accounted for the magnitude of the difference" between the groups, said Deborah Cory-Slechta, an environmental medicine professor at the University of Rochester medical school.
"This is a pretty strong damnation of" phthalates, she said. "It needs to be replicated. But I still think this makes a very strong case for getting rid of these compounds" in infant intensive care units, she said.
Click for related content
Unraveling how kids become bilingual so easilyHalf of all bathtub injuries involve toddlersBeachgoers beware: Stomach bugs lurk in sand
Edmund Crouch, a scientist who served with the Rochester professor on a National Research Council committee on phthalates risks, was skeptical and said the study doesn't rule out other factors that might have caused liver problems.
Steve Risotto of the American Chemistry Council, which represents chemical makers, also disputed the results and said the study "doesn't show any direct cause and effect."
But Beth Lyman, a pediatric nutrition nurse at Children's Mercy Hospital in Kansas City, called the results intriguing. Her hospital switched to phthalate-free feeding systems more than a decade ago. Lyman said she'd noticed fewer liver problems in IV-fed infants since then, and that the study makes her wonder if the switch might have contributed.
The small study in a German hospital suggests a chemical known as a phthalate, used in some intravenous feeding bags and tubing, may raise preemies' chances for liver damage.
Rigorous research on phthalates' effects in humans is lacking, and at least one expert found the German study unconvincing. There is no solid proof implicating the phthalate studied, DEHP.
However, the researchers said their results show that hospitals treating newborns or preemies should turn to IV feeding equipment that doesn't contain DEHP. Some hospitals in the U.S. already have switched.
Premature babies' livers are immature so they are already at risk for liver complications. They also are often fed intravenously, a practice already known to increase liver problems. The new study, published Monday in the journal Pediatrics, says one possible reason is DEHP. Animal studies suggest the phthalate chemical may cause various health risks including liver abnormalities and reproductive system damage.
Also found in toys, vinyl flooringPhthalates (pronounced thowl-ates) are found in many products besides medical supplies — toys, vinyl flooring and cosmetics. They're used to stabilize fragrances and make plastics flexible. Some countries and California have restricted their use.
They are different from bisphenol-A, or BPA, a plastic-hardening chemical that also has raised health concerns and is found in food containers and other products. It's no longer used in many baby bottles.
In a 2002 phthalates advisory, the Food and Drug Administration recommended alternatives for patients most at risk from the chemical leeching out of plastic medical equipment, including sick infant boys because of possible damage to developing reproductive organs.
Liver issues with half preemies exposed to DEHPThe German study involved 30 mostly premature infants treated in a Mannheim intensive care unit before the hospital switched to feeding equipment without the chemical, and 46 infants treated there afterward.
Serious liver problems involving reduced flow of bile, a digestive fluid produced by the liver, developed in 50 percent of the infants fed with the tubes containing DEHP versus just 13 percent of the other infants.
The researchers took into account other factors that might contribute to liver problems, and the two groups were mostly similar. However, the chemical group was intravenously fed for an average of 26 days, four more days than the other infants.
That is a limitation that could have skewed the results. But that alone "wouldn't have accounted for the magnitude of the difference" between the groups, said Deborah Cory-Slechta, an environmental medicine professor at the University of Rochester medical school.
"This is a pretty strong damnation of" phthalates, she said. "It needs to be replicated. But I still think this makes a very strong case for getting rid of these compounds" in infant intensive care units, she said.
Click for related content
Unraveling how kids become bilingual so easilyHalf of all bathtub injuries involve toddlersBeachgoers beware: Stomach bugs lurk in sand
Edmund Crouch, a scientist who served with the Rochester professor on a National Research Council committee on phthalates risks, was skeptical and said the study doesn't rule out other factors that might have caused liver problems.
Steve Risotto of the American Chemistry Council, which represents chemical makers, also disputed the results and said the study "doesn't show any direct cause and effect."
But Beth Lyman, a pediatric nutrition nurse at Children's Mercy Hospital in Kansas City, called the results intriguing. Her hospital switched to phthalate-free feeding systems more than a decade ago. Lyman said she'd noticed fewer liver problems in IV-fed infants since then, and that the study makes her wonder if the switch might have contributed.
Sunday, July 26, 2009
Study: Tropical rain band is shifting north
We're talking about the most prominent rainfall feature on the planet, one that many people depend on as the source of their freshwater because there is no groundwater to speak of where they live," said Julian Sachs, associate professor of oceanography at the University of Washington and lead author of the paper. "In addition many other people who live in the tropics but farther afield from the Pacific could be affected because this band of rain shapes atmospheric circulation patterns throughout the world."
While water is increasingly becoming a hot commodity around the globe, there is no global water shortage. Human demand for water has tripled in the past 50 years, by some estimates. Yet Earth has essentially as much water now as ever — about 360 quintillion gallons.
Rather, human populations put ever more pressure on local and regional water resources, which in some cases — such as the American Southwest — are dwindling with climate change. The water still exists, it just gets dumped elsewhere.
The band of tropical rainfall is created at what scientists call the intertropical convergence zone. There, just north of the equator, trade winds from the northern and southern hemispheres collide where heat pours into the atmosphere from the tropical sun. Rain clouds up to 30,000 feet thick dump as much as 13 feet of rain a year in some places.
The amount of rain in the zone actually increased between 1979 and 2005, this video shows.
The band is thought to have hugged the equator 350 years ago, during the planet's Little Ice Age (roughly 1400 to 1850).
From dry to downpours
The authors analyzed natural records of rainfall (including microbes and chemical ratios) left in annual layers of lake and lagoon sediments from four Pacific islands at or near the equator.
Washington Island, about 5 degrees north of the equator, is now at the southern edge of the intertropical convergence zone and receives nearly 10 feet of rain a year. But during the Little Ice Age it was arid. A similar arid past was found for Palau, which lies about 7 degrees north of the equator and in the heart of the modern convergence zone.
In contrast, the researchers present evidence that the Galapagos Islands, today an arid place on the equator in the Eastern Pacific, had a wet climate during the Little Ice Age.
"If the intertropical convergence zone was 550 kilometers, or 5 degrees, south of its present position as recently as 1630, it must have migrated north at an average rate of 1.4 kilometers — just less than a mile — a year," Sachs said in a statement. "Were that rate to continue, the intertropical convergence zone will be 126 kilometers — or more than 75 miles — north of its current position by the latter part of this century."
The work was funded by the National Science Foundation, National Oceanic and Atmospheric Administration and the Gary Comer Science and Education Foundation.Earth's most prominent rain band, near the equator, has been moving north at an average rate of almost a mile a year for three centuries, likely because of a warming world, scientists say.
The band supplies fresh water to almost a billion people and affects climate elsewhere.
If the migration continues, some Pacific islands near the equator that today enjoy abundantrainfall may be starved of freshwater by midcentury or sooner, researchers report in the July issue of the journal Nature Geoscience.
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