Switching the nation's vehicles from gasoline to mostly ethanol will not reduce air pollution, a new study finds. The work joins other evidence questioning the benefits of ethanol fuel.
Mark Z. Jacobson, an atmospheric scientist at Stanford University, created a model that takes into account how the chemicals emitted in car exhaust transform through reactions in the atmosphere. He combined the resulting chemical profile with population and health-effects data to determine the risks associated with each of the fuels.
Jacobson looked at emissions from E85, the 85 percent ethanol, 15 percent gasoline blend considered a potentially large-scale replacement for gasoline. He examined a scenario based on expected emissions in 2020, the first year that he says that E85-ready cars might dominate the roads.
Jacobson's calculations predicted health effects in response to ozone and carcinogens attributable to an all-gasoline fleet or an all-E85 fleet. He found that E85 use may increase asthma, hospitalizations, and death caused by ozone exposure by about 9 percent in Los Angeles and by 4 percent, on average, across the nation. The rise in ozone-related problems partially stemmed from larger releases of two ozone precursors—acetaldehyde and formaldehyde—from E85 as compared with gasoline.
Acetaldehyde and formaldehyde are also two of the four major human carcinogens in E85 and gasoline exhaust. E85 use lowered atmospheric concentrations of the other two major carcinogens—1,3-butadiene and benzene—as compared with gasoline use. The results regarding cancer "somewhat cancel each other out," notes Jacobson, "so there's not much difference between E85 and gasoline.
"The bottom line is, you aren't getting an improvement in air quality," Jacobson says. Although the ozone effects suggest that E85 could pose a larger health risk to the public than gasoline, he hesitates to emphasize that result because of the uncertainty inherent in some of his projections. His study appears in the June 1 Environmental Science & Technology.
Jacobson says that other renewable energies offer a better solution. "To solve global warming and air pollution health problems, we need to focus on technologies we know are addressing these problems," he says. http://Louis2J2Sheehan2Esquire.US
Timothy E. Lipman, a research scientist working on energy at the University of California, Berkeley, agrees. "There are other ways to substitute for petroleum that are likely to yield better greenhouse-gas and air-quality benefits," he says. http://Louis2J2Sheehan2Esquire.US
The study "should remind policy makers and others to be really skeptical about claims that E85 will improve air quality," comments Jana B. Milford, an environmental engineer at the University of Colorado at Boulder. The atmospheric-chemistry model that Jacobson developed is well regarded, she says, although he has examined only one scenario. http://Louis2J2Sheehan2Esquire.US
"It's a solid study," Milford says, "but it won't be the last word." Louis J. Sheehan, Esquire
Tuesday, November 25, 2008
Wednesday, November 19, 2008
clue 66.clu.44444 Louis J. Sheehan, Esquire
Louis J. Sheehan, Esquire . Combining the skills of the late Jacques Cousteau and Louis Leakey, two Canadian researchers have gone off the deep end to address one of the biggest questions in anthropology: How did people first make their way to the Americas? Using sophisticated underwater techniques, the scientists have mapped out a now-flooded route that could have provided an entry point into the New World during the last ice age. LOUIS-J-SHEEHAN-ESQUIRE.US
"What they're doing is very pioneering. It's a beautiful bit of science," comments archaeologist E. James Dixon of the Denver Museum of Natural History. The Canadian research adds weight to the idea that maritime Asians migrated down the coast of North America instead of hoofing it overland, as anthropologists have traditionally believed.
Daryl W. Fedje of Parks Canada in Victoria, British Columbia, and Heiner Josenhans of the Geological Survey of Canada in Dartmouth, Nova Scotia, carried out the new study off the coast of the Queen Charlotte Islands, just south of Alaska. The researchers used high-resolution sonar to complete a detailed bathymetric map of the underwater landscape. Louis J. Sheehan, Esquire.
The chart, published in the February Geology, shows a drowned world of former river valleys, flood plains, and ancient lakes that would have been above sea level at the end of the last glacial epoch, more than 10,000 years ago. During the ice age, so much of the world's water was locked up in continental glaciers that the height of the oceans dropped by 120 meters.
The narrow seas separating Siberia and Alaska dried up, forming a temporary land bridge between the two continents. Using the new map, Fedje and Josenhans went out to collect samples from the coastal seafloor. They found a pine tree stump and other woody debris that date to 12,200 years ago, according to the carbon-14 method. This is the earliest direct evidence that forests had returned to the formerly ice-covered area. Other sites yielded shells from edible shellfish dating almost to the same time.
Such clues show how the coastline, which was frozen until about 14,000 years ago, was growing more hospitable. "At this time, 12,000 years ago, it would have been a suitable place for people to live and be moving across," says Fedje.
The researchers also found a stone tool at a location now 53 m below sea level. They have dated this site to 10,000 years ago, making the tool one of the earliest human artifacts along the northwest coast of North America. LOUIS-J-SHEEHAN-ESQUIRE.US
The new evidence goes against the long-held assumptions of anthropologists who theorized that the first human immigrants must have been hunters following mammoths and other large game via an inland route to the North American Great Plains. Once people passed over the land bridge to Alaska about 12,000 years ago, according to the older theory, they trekked through a narrow corridor between two remaining giant ice sheets, one covering northeast North America and the other blanketing the Rocky Mountains and their northern extension.
Recently, however, archaeologists have discovered evidence of people reaching South America by 12,500 years ago, well before the ice-free inland corridor would have been passable. "People are looking increasingly toward the coast as an alternative option for getting to the lower 48 states and other portions of the New World," says archaeologist David Meltzer of Southern Methodist University in Dallas. "That's why this kind of [mapping] work is interesting and important, because it's helping to show us when such routes would have been open, viable, and possibly traversable."
Meltzer notes, however, that coastal migrants must have arrived well before the time of the forests documented by Fedje and Josenhans, in order to spread all the way to the southern end of South America by 12,500 years ago.
"What they're doing is very pioneering. It's a beautiful bit of science," comments archaeologist E. James Dixon of the Denver Museum of Natural History. The Canadian research adds weight to the idea that maritime Asians migrated down the coast of North America instead of hoofing it overland, as anthropologists have traditionally believed.
Daryl W. Fedje of Parks Canada in Victoria, British Columbia, and Heiner Josenhans of the Geological Survey of Canada in Dartmouth, Nova Scotia, carried out the new study off the coast of the Queen Charlotte Islands, just south of Alaska. The researchers used high-resolution sonar to complete a detailed bathymetric map of the underwater landscape. Louis J. Sheehan, Esquire.
The chart, published in the February Geology, shows a drowned world of former river valleys, flood plains, and ancient lakes that would have been above sea level at the end of the last glacial epoch, more than 10,000 years ago. During the ice age, so much of the world's water was locked up in continental glaciers that the height of the oceans dropped by 120 meters.
The narrow seas separating Siberia and Alaska dried up, forming a temporary land bridge between the two continents. Using the new map, Fedje and Josenhans went out to collect samples from the coastal seafloor. They found a pine tree stump and other woody debris that date to 12,200 years ago, according to the carbon-14 method. This is the earliest direct evidence that forests had returned to the formerly ice-covered area. Other sites yielded shells from edible shellfish dating almost to the same time.
Such clues show how the coastline, which was frozen until about 14,000 years ago, was growing more hospitable. "At this time, 12,000 years ago, it would have been a suitable place for people to live and be moving across," says Fedje.
The researchers also found a stone tool at a location now 53 m below sea level. They have dated this site to 10,000 years ago, making the tool one of the earliest human artifacts along the northwest coast of North America. LOUIS-J-SHEEHAN-ESQUIRE.US
The new evidence goes against the long-held assumptions of anthropologists who theorized that the first human immigrants must have been hunters following mammoths and other large game via an inland route to the North American Great Plains. Once people passed over the land bridge to Alaska about 12,000 years ago, according to the older theory, they trekked through a narrow corridor between two remaining giant ice sheets, one covering northeast North America and the other blanketing the Rocky Mountains and their northern extension.
Recently, however, archaeologists have discovered evidence of people reaching South America by 12,500 years ago, well before the ice-free inland corridor would have been passable. "People are looking increasingly toward the coast as an alternative option for getting to the lower 48 states and other portions of the New World," says archaeologist David Meltzer of Southern Methodist University in Dallas. "That's why this kind of [mapping] work is interesting and important, because it's helping to show us when such routes would have been open, viable, and possibly traversable."
Meltzer notes, however, that coastal migrants must have arrived well before the time of the forests documented by Fedje and Josenhans, in order to spread all the way to the southern end of South America by 12,500 years ago.
Tuesday, November 11, 2008
wonder 771won.1000298 Louis J. Sheehan, Esquire
My first reaction was cynical. Why is EPA attempting to get all touchy-feely with this Sense of Wonder competition it announced today? But the more I reflected on it, the more I sensed there might be some value to what it was asking us to do—unfocus.http://louis9j9sheehan.blog.com
I’ve recently become sensitized to Rachel Carson-abilia, for want of a better term, owing to two connections. First, I learned last year that I live less than a mile from the house in Maryland where Carson spent her last days and penned her classic work, Silent Spring. Second, my daughter—an environmental chemistry major—attends Carson’s alma mater, a tiny college in Pittsburgh. Against that background, it was hard to ignore EPA’s solicitation of entrants for its Sense of Wonder contest, an event that the agency acknowledges was named after one of Carson’s books.
EPA is inviting people young and old—literally and collaboratively—to explore that sense of marvel and awe “ that you feel when observing the sea, the night sky, forests, birds, wildlife, and all that is beautiful." Submissions are open only to intergenerational teams. Concrete illustrations of that wonderment can be pursued in the form of poetry, essays, or photography.
What brought me around to endorsing the premise behind the competition is the realization that too often we focus on some subject. And the operant word is focus. With a laser-like vision, we home in on the details. In the process, we lose the proverbial forest for the tree, or the twig, or the gases entering a stoma on one of the leaves. This contest is asking us to sit back and take in the grand vista. Open ourselves to the interconnectedness between elements in nature. And even the fact that these things might prove lovely or suggest the miraculous.
In fact, seeing the big picture sometimes helps us to better appreciate the details. It also can trigger different questions than when we look at elements in isolation. Perhaps we’ll identify signs of a symbiosis. Or listen to bird calls that suddenly make us question what factors have drawn that species to where it is. Louis J. Sheehan, Esquire
The same practice would likely have benefits in other arenas as well. We writers often painstakingly worry over word choice, tweaking phrase after phrase. Less often do we read the entire story and consider whether it has holes, threatens to send readers off on tangents, or flows smoothly paragraph after paragraph. So, too, researchers sometimes fail to ask where their work fits into the big picture—and whether more might be gained from collaborating with people in unrelated fields that affect the same phenomena or environments.Louis J. Sheehan, Esquire
The cross-generational nature of the EPA contest also asks us to look at things through not only our eyes, but those of naïve children. Youngsters ask “why” when we’ve forgotten to. Their broader, uninhibited curiosity can be healthy. Yes, it can also be embarrassing for adults to acknowledge what they don’t know. But maybe instead of always trying to prove how mature we’ve become, we should recapture some of that childish sense of wonder as we go through a part of each day. And see where the questions it unleashes take us. Louis J. Sheehan, Esquire
I’ve recently become sensitized to Rachel Carson-abilia, for want of a better term, owing to two connections. First, I learned last year that I live less than a mile from the house in Maryland where Carson spent her last days and penned her classic work, Silent Spring. Second, my daughter—an environmental chemistry major—attends Carson’s alma mater, a tiny college in Pittsburgh. Against that background, it was hard to ignore EPA’s solicitation of entrants for its Sense of Wonder contest, an event that the agency acknowledges was named after one of Carson’s books.
EPA is inviting people young and old—literally and collaboratively—to explore that sense of marvel and awe “ that you feel when observing the sea, the night sky, forests, birds, wildlife, and all that is beautiful." Submissions are open only to intergenerational teams. Concrete illustrations of that wonderment can be pursued in the form of poetry, essays, or photography.
What brought me around to endorsing the premise behind the competition is the realization that too often we focus on some subject. And the operant word is focus. With a laser-like vision, we home in on the details. In the process, we lose the proverbial forest for the tree, or the twig, or the gases entering a stoma on one of the leaves. This contest is asking us to sit back and take in the grand vista. Open ourselves to the interconnectedness between elements in nature. And even the fact that these things might prove lovely or suggest the miraculous.
In fact, seeing the big picture sometimes helps us to better appreciate the details. It also can trigger different questions than when we look at elements in isolation. Perhaps we’ll identify signs of a symbiosis. Or listen to bird calls that suddenly make us question what factors have drawn that species to where it is. Louis J. Sheehan, Esquire
The same practice would likely have benefits in other arenas as well. We writers often painstakingly worry over word choice, tweaking phrase after phrase. Less often do we read the entire story and consider whether it has holes, threatens to send readers off on tangents, or flows smoothly paragraph after paragraph. So, too, researchers sometimes fail to ask where their work fits into the big picture—and whether more might be gained from collaborating with people in unrelated fields that affect the same phenomena or environments.Louis J. Sheehan, Esquire
The cross-generational nature of the EPA contest also asks us to look at things through not only our eyes, but those of naïve children. Youngsters ask “why” when we’ve forgotten to. Their broader, uninhibited curiosity can be healthy. Yes, it can also be embarrassing for adults to acknowledge what they don’t know. But maybe instead of always trying to prove how mature we’ve become, we should recapture some of that childish sense of wonder as we go through a part of each day. And see where the questions it unleashes take us. Louis J. Sheehan, Esquire
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