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
Monday, July 27, 2009
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.
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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.
White House creates climate analysis job
A scientist from the University of Rhode Island who headed research expeditions in the Arctic and the Indian Ocean will soon join the White House in a new position that targets the worldwide issue of climate change.
Kate Moran, associate dean of URI's Graduate School of Oceanography, begins work Monday as a senior policy analyst for President Barack Obama's Office of Science & Technology Policy. In her new role, Moran will provide advice on issues relating to oceans, the Arctic and global warming.
"Climate affects all aspects of our life, our food, our energy, our politics," Moran said in a telephone interview this week as she hurried to pack for her move to Washington. "It affects defense, security, and so it's crosscutting."
Trained as an engineer, Moran was the co-chair of an Arctic expedition in 2004 that sent scientists to the ice-clogged waters above the Lomonosov Ridge, about 155 miles from the North Pole. The expedition drilled first-of-their-kind core samples from the floor of the Arctic Ocean.
The samples showed that temperatures in the Arctic reached an average 74 degrees during a period of global warming about 55 million years ago, a surprise to scientists who previously believed the polar regions would have remained cooler.
Moran also helped lead the first research team to investigate the sea floor at the site of the 2004 earthquake that triggered a deadly tsunami in the Indian Ocean that killed 230,000 people in a dozen countries. The research team debunked the theory that underwater landslides strengthened the tsunami, showing that existing models used to predict and study tsunamis must be revised.
Closer to home, Moran has become known in the public debate over global warming. She testified last year before a U.S. Senate panel that climate change and its human causes are "unequivocal." She supports a proposal to build a massive wind farm miles off Rhode Island's coast, meant to provide 15 percent of the state's electricity needs and reduce the state's reliance on fossil-fuel power plants.
"I think scientists should be more active in speaking about their own science," she said.
Moran made similar statements about global warming last year during a public presentation on climate change held at URI's campus, eliciting hostile questions from audience members who did not believe global warming or doubted that humans contribute to it, said Peter August, a URI professor of natural resource science.
She didn't flinch during the exchanges, showing skills that August thinks could be helpful in Washington.
"She can hold her ground, she can speak with objective authority," August said. "She doesn't get upset, and she doesn't make people look stupid.
Warm Caribbean, Gulf seas threaten corals
Warm ocean temperatures predicted to persist through October in the Caribbean and the central Gulf of Mexico could mean the loss of huge swaths of corals across those regions, U.S. scientists warned Wednesday.
The National Oceanic and Atmospheric Administration's Coral Reef Watch network said the conditions may lead to coral disease outbreaks and bleaching, when the stressed organisms expel the colorful algae living in their tissues, leaving a whitish color.
Coral bleaching that lasts more than a week can kill the organisms, since they rely on the algae for sustenance, leading to the loss of reef habitat for numerous marine species.
Sea surface temperatures in parts of the Caribbean are already at levels typically not seen until late summer months when the water is hottest, said C. Mark Eakin, coordinator of NOAA's Coral Reef Watch.
Bleaching can occur when sea temperatures rise just a few degrees above the average of the warmest summer months in these areas where coral reefs live. The general average for the hottest summer months in the Caribbean is about 84 degrees Fahrenheit, Eakin said.
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Scientists fear the bleaching could exceed what was seen in 2005 in the Caribbean, the worst coral bleaching event in the region's recorded history. In parts of the eastern Caribbean four years ago, up to 90 percent of corals suffered bleaching, with more than half dying.
"Just like any climate forecast, local conditions and weather events can influence actual temperatures. However, we are quite concerned that high temperatures may threaten the health of coral reefs in the Caribbean this year," Eakin said.
NOAA also warned of potential high sea temperatures stressing corals near the central Pacific islands of Kiribati, and between the Northern Mariana Islands and Japan.
Scientists hope the early warnings of potential coral stress will lead governments to take protective steps, including establishing temporary restrictions on users of coral reefs in the areas, such as divers, boaters and anglers
Corals around the world are being stressed by rising sea temperatures, causing bleaching events that expose the organisms to disease and death. Carbon dioxide released by burning fossil fuels is absorbed by the oceans, making the waters more acidic and corrosive on corals. Land-based pollution, such as sewage, beach erosion, coastal development and overfishing also are to blame, experts say.
About 25 percent of all marine species need coral reefs to live and grow, while 40 percent of fish caught commercially and consumed worldwide use reefs to breed.
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