Almost every news story about global warming recommends that consumers switch from incandescent light bulbs to more efficient compact fluorescent light bulbs, or CFLs.
But are CFLs really that good for the environment?
Incandescent light bulbs use electricity to heat a filament to a white-hot state, producing light. Yet 90 percent of the energy used is wasted as heat, according to General Electric's Web site.
Compact fluorescent light bulbs use electricity to excite gas within a glass tube. The gas fluoresces, producing ultraviolet light which the human eye cannot see. This UV light then reacts with mercury and a phosphorescent chemical compound inside the tube to create visible light.
Because CFL bulbs do not use heat as the lighting mechanism, less energy is spent to create an equivalent amount of light.
• Click here to visit FOXBusiness.com's Energy Center.
The packaging of an N:Vision-brand CFL bulb purchased at Home Depot, for example, states that it uses only 14 watts to produce the same amount of light, as measured in lumens, as a 60-watt incandescent bulb.
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This decreased demand for electricity reduces the need for electrical generation, which environmentalists point out reduces emissions from coal-fired plants.
In February, Australia announced a nationwide ban on incandescent bulbs, which will go into effect in 2010. The country's environment minister said the move will cut greenhouse-gas emissions by 800,000 tons by 2012, according to Reuters.
But this assumes that Australians will significantly reduce their current levels of electrical consumption.
What if a consumer who has a $100 monthly electric bill reduces it to $50 by installing CFLs, but then leaves the new lights on longer, because he's already accustomed to paying $100 per month?
The consumer would be using less raw electricity than before, but not that much less.
"Sometimes when you cut the cost of things, people use more of them," said James S. Shortle, professor of environmental economics at Penn State University.
"People have a certain lighting requirement," said Shortle, and they would be happy to fulfill that need more cheaply.
He suggested that people probably would not turn on their lights more often. "What they might not do is turn them off."
Manufacturers, meanwhile, tout the savings to consumers in reduced electrical costs over the lifetime of the CFL bulb.
The 14-watt N:Vision states on the packaging that it will save the buyer $46 over its lifetime. How did the manufacturer arrive at that number?
CFL makers claim the bulbs have lifetimes of 10,000 hours each, whereas most equivalent 60-watt incandescent bulbs last 1,000 hours.
Based on a rate of $0.10 per kilowatt-hour, a CFL costs $14 to power over its lifetime. The consumer would go through 10 incandescent bulbs in that time, costing a total of $60. Hence, a difference of $46 in electric costs per light fixture.
Since CFLs last longer than incandescents, consumers have to buy fewer bulbs for their fixtures, but here the cost savings are trivial.
At $3.97 for a four-pack of N:Visions versus $1.04 for four Philips incandescents, and assuming 10 incandescents used for every CFL used, a consumer opting for the N:Vision would save about $1.60 per fixture in addition to the electricity conserved.
You won't save a lot of scratch on the bulbs themselves, but at least you'll spend less time changing them.
But what about any drawbacks to CFLs?
CFLs don't operate well in frigid conditions, limiting their use for exterior lighting in cold areas.
According to a spokeswoman from Philips Lighting, most CFLs require a minimum starting temperature of minus 20 degrees Fahrenheit; below that, it's difficult for the bulb's reaction process to begin.
Other problems in cold temps include reduced light output and a pinkish glow, rather than the desirable "soft white" (actually faintly yellow) color.
Those problems alone may make nationwide bans on incandescent bulbs impractical in parts of the United States. Winter temperatures in Australia's southernmost state of Tasmania average 52 degrees Fahrenheit, but Minnesota spends most of its winters between 6 and 16 degrees F.
The bigger problem with CFLs is their mercury content.
Along with the phosphor, which can be one or many of several chemical compounds, mercury helps shift the invisible UV light into the visible part of the spectrum.
The National Electrical Manufacturers Association, or NEMA, which sets voluntary industry standards, suggests that CFLs of 25 watts or less — the equivalent of a 100-watt incandescent bulb — contain no more than 5 milligrams of mercury, the size of the tip of a ballpoint pen.
Both CFL manufacturers and the Environmental Protection Agency recommend recycling CFL bulbs, since breaking or incinerating them releases mercury into the air. The poisonous metal can then find its way into soil, water, fish and fish-eating humans.
Sites such as epa.gov/bulbrecycling, lamprecycle.org and earth911.org offer information about where CFLs can be recycled, and certain retailers such as IKEA accept used CFLs for recycling.
Should you break out the hazmat suit if you break a CFL at home? The EPA offers a checklist at epa.gov/mercury that suggests you leave the room for 15 minutes, then return to sweep up and double-bag the mess — and not to vacuum unless absolutely necessary.
So handle with care, lest you end up like Brandy Bridges of Prospect, Maine, who broke a CFL bulb in her daughter's room in March and was told that professional environmental cleaning would cost about $2,000.
According to the Maine Department of Environmental Protection, Bridges was concerned about any amount of mercury in her house, even at levels far below the state hazard threshold. (Hazardous levels were found on an area of carpet "the size of a dinner plate.")
It was in response to her "nervousness" that the DEP responder who came to her house recommended the cleanup service.
Two months after the incident, state DEP officials came back and found no mercury hazard. Even so, they removed the piece of carpet — which Bridges had planned to take up even before the bulb was broken — at her request.
• Click here for the Maine DEP's account of the events (pdf).
In the meantime, manufacturers are racing for bragging rights to the CFL with the lowest mercury content. Philips says that it sells 19 CFL products at Wal-Mart that contain 40 percent to 60 percent less mercury than the suggested NEMA level of 5 milligrams.
Whether decreases in power-plant emissions are offset by people releasing mercury into the environment by disposing of their CFLs improperly remains to be seen.
One thing's for sure: Using compact fluorescent light bulbs makes sense for anyone paying an electric bill — and who doesn't have butterfingers.
Monday, June 22, 2009
Green tea may affect prostate cancer progression
According to results of a study published in Cancer Prevention Research, a journal of the American Association for Cancer Research, men with prostate cancer who consumed the active compounds in green tea demonstrated a significant reduction in serum markers predictive of prostate cancer progression.
"The investigational agent used in the trial, Polyphenon E (provided by Polyphenon Pharma) may have the potential to lower the incidence and slow the progression of prostate cancer," said James A. Cardelli, Ph.D., professor and director of basic and translational research in the Feist-Weiller Cancer Center, LSU Health Sciences Center-Shreveport.
Green tea is the second most popular drink in the world, and some epidemiological studies have shown health benefits with green tea, including a reduced incidence of prostate cancer, according to Cardelli. However, some human trials have found contradictory results. The few trials conducted to date have evaluated the clinical efficacy of green tea consumption and few studies have evaluated the change in biomarkers, which might predict disease progression.
Cardelli and colleagues conducted this open-label, single-arm, phase II clinical trial to determine the effects of short-term supplementation with green tea's active compounds on serum biomarkers in patients with prostate cancer. The biomarkers include hepatocyte growth factor (HGF), vascular endothelial growth factor (VEGF) and prostate specific antigen (PSA). HGF and VEGF are good prognostic indicators of metastatic disease.
The study included 26 men, aged 41 to 72 years, diagnosed with prostate cancer and scheduled for radical prostatectomy. Patients consumed four capsules containing Polyphenon E until the day before surgery — four capsules are equivalent to about 12 cups of normally brewed concentrated green tea, according to Cardelli. The time of study for 25 of the 26 patients ranged from 12 days to 73 days, with a median time of 34.5 days.
Findings showed a significant reduction in serum levels of HGF, VEGF and PSA after treatment, with some patients demonstrating reductions in levels of greater than 30 percent, according to the researchers.
Cardelli and colleagues found that other biomarkers were also positively affected. There were only a few reported side effects associated with this study, and liver function remained normal.
Results of a recent year-long clinical trial conduced by researchers in Italy demonstrated that consumption of green tea polyphenols reduced the risk of developing prostate cancer in men with high-grade prostate intraepithelial neoplasia (HGPIN).
"These studies are just the beginning and a lot of work remains to be done, however, we think that the use of tea polyphenols alone or in combination with other compounds currently used for cancer therapy should be explored as an approach to prevent cancer progression and recurrence," Cardelli said.
William G. Nelson, V., M.D., Ph.D., professor of oncology, urology and pharmacology at the Johns Hopkins Kimmel Cancer Center, believes the reduced serum biomarkers of prostate cancer may be attributable to some sort of benefit relating to green tea components.
"Unfortunately, this trial was not a randomized trial, which would have been needed to be more sure that the observed changes were truly attributable to the green tea components and not to some other lifestyle change (better diet, taking vitamins, etc.) men undertook in preparation for surgery," added Nelson, who is also a senior editor for Cancer Prevention Research. However, "this trial is provocative enough to consider a more substantial randomized trial."
In collaboration with Columbia University in New York City, the researchers are currently conducting a comparable trial among patients with breast cancer. They also plan to conduct further studies to identify the factors that could explain why some patients responded more dramatically to Polyphenon E than others. Cardelli suggested that additional controlled clinical trials should be done to see if combinations of different plant polyphenols were more effective than Polyphenon E alone.
"There is reasonably good evidence that many cancers are preventable, and our studies using plant-derived substances support the idea that plant compounds found in a healthy diet can play a role in preventing cancer development and progression," said Cardelli
"The investigational agent used in the trial, Polyphenon E (provided by Polyphenon Pharma) may have the potential to lower the incidence and slow the progression of prostate cancer," said James A. Cardelli, Ph.D., professor and director of basic and translational research in the Feist-Weiller Cancer Center, LSU Health Sciences Center-Shreveport.
Green tea is the second most popular drink in the world, and some epidemiological studies have shown health benefits with green tea, including a reduced incidence of prostate cancer, according to Cardelli. However, some human trials have found contradictory results. The few trials conducted to date have evaluated the clinical efficacy of green tea consumption and few studies have evaluated the change in biomarkers, which might predict disease progression.
Cardelli and colleagues conducted this open-label, single-arm, phase II clinical trial to determine the effects of short-term supplementation with green tea's active compounds on serum biomarkers in patients with prostate cancer. The biomarkers include hepatocyte growth factor (HGF), vascular endothelial growth factor (VEGF) and prostate specific antigen (PSA). HGF and VEGF are good prognostic indicators of metastatic disease.
The study included 26 men, aged 41 to 72 years, diagnosed with prostate cancer and scheduled for radical prostatectomy. Patients consumed four capsules containing Polyphenon E until the day before surgery — four capsules are equivalent to about 12 cups of normally brewed concentrated green tea, according to Cardelli. The time of study for 25 of the 26 patients ranged from 12 days to 73 days, with a median time of 34.5 days.
Findings showed a significant reduction in serum levels of HGF, VEGF and PSA after treatment, with some patients demonstrating reductions in levels of greater than 30 percent, according to the researchers.
Cardelli and colleagues found that other biomarkers were also positively affected. There were only a few reported side effects associated with this study, and liver function remained normal.
Results of a recent year-long clinical trial conduced by researchers in Italy demonstrated that consumption of green tea polyphenols reduced the risk of developing prostate cancer in men with high-grade prostate intraepithelial neoplasia (HGPIN).
"These studies are just the beginning and a lot of work remains to be done, however, we think that the use of tea polyphenols alone or in combination with other compounds currently used for cancer therapy should be explored as an approach to prevent cancer progression and recurrence," Cardelli said.
William G. Nelson, V., M.D., Ph.D., professor of oncology, urology and pharmacology at the Johns Hopkins Kimmel Cancer Center, believes the reduced serum biomarkers of prostate cancer may be attributable to some sort of benefit relating to green tea components.
"Unfortunately, this trial was not a randomized trial, which would have been needed to be more sure that the observed changes were truly attributable to the green tea components and not to some other lifestyle change (better diet, taking vitamins, etc.) men undertook in preparation for surgery," added Nelson, who is also a senior editor for Cancer Prevention Research. However, "this trial is provocative enough to consider a more substantial randomized trial."
In collaboration with Columbia University in New York City, the researchers are currently conducting a comparable trial among patients with breast cancer. They also plan to conduct further studies to identify the factors that could explain why some patients responded more dramatically to Polyphenon E than others. Cardelli suggested that additional controlled clinical trials should be done to see if combinations of different plant polyphenols were more effective than Polyphenon E alone.
"There is reasonably good evidence that many cancers are preventable, and our studies using plant-derived substances support the idea that plant compounds found in a healthy diet can play a role in preventing cancer development and progression," said Cardelli
Pythons Grow Bigger Hearts at Mealtimes
Burmese pythons like a meal they can really get their fangs around, especially since the snakes are known to go half a year or more between meals. That gustatory pause is merely one of pythons' more remarkable adaptations.
New research shows that when the reptiles swallow whole rats, birds, and other prey, the pythons' hearts temporarily grow bigger.Scientists in California say the snakes experience a 40 percent increase in heart muscle mass within 48 hours of feeding. The change enables the pythons to meet the metabolic demands of digesting a meal.
What's more, the process is fully reversible, with the snakes' hearts shrinking back to their original size once feeding ends.
Pythons can offer new insights to understanding heart growth in other species, including humans, according to researchers behind the discovery, which is reported in the current issue of the science journal Nature.
One of the world's largest snakes, the Burmese python can grow as long as 25 feet (7.6 meters) and weigh as much as 200 pounds (90 kilograms). Native to Southeast Asia, it preys on mammals, birds, and other animals, which the reptile swallows whole. But python meals are few and far between.
"These animals have a remarkable ability to shut down their metabolism between meals," said James Hicks, a professor of ecology and evolutionary biology at the University of California, Irvine.
"We currently have 1.5-kilogram [3.3-pound] pythons in the lab that have not eaten for three months and have only lost one to ten grams [four to thirty-five hundredths of an ounce] of weight," noted Hicks, who is also the study's lead author.
But when these reptiles do feed, Hicks added, they often tackle prey that is 50 to 100 percent the size of their own body mass. Such meals require a considerable digestive effort.
"Some investigators have reported as much as a 44-fold increase in metabolism during digestion," Hicks said.
Metabolic Demands
Hicks and his colleagues investigated how Burmese pythons meet the metabolic demands of digestion.
They found that oxygen consumption rose sevenfold in lab pythons after feeding. This was accompanied by an extraordinarily rapid growth in heart size. The snakes' heart ventricle muscle mass (ventricles are the heart's pumping chambers) increased 40 percent in just two days.
The study team was able to link this sudden growth to increased production of a cardiac protein. The protein is associated with cells that enlarge the heart and boost its pumping capacity, a condition known as cardiac hypertrophy.
The researchers say feeding-induced cardiac hypertrophy likely explains why Burmese pythons pump 50 percent more blood per heartbeat while quietly digesting a meal than when slithering at full speed.
Previous studies point to why python hearts need to go into overdrive when these animals digest food. Researchers report livers growing to three times their normal size, intestines doubling in mass, and pancreatic enzyme activity increasing threefold. Such changes within the snake significantly raise the demand for oxygenated blood.
Stephen Secor, a biologist at the University of Alabama in Birmingham, is among those to have studied digestion in pythons. While most carnivores are able chew, tear up, or crush their prey first, snakes "swallow only intact prey and must delegate to the stomach the whole job of breaking [it] down," Secor said.
Yet once a python has finished its meal, its heart quickly returns to its usual size.
Heart Remodeling
Hicks, the University of California ecologist and evolutionary biologist, said that by quickly remodeling their hearts depending on whether they are feeding or fasting, Burmese pythons are able to match their metabolism to their bodily needs.
Hicks said he is unaware of any other animal that is able to do this with such speed.
His lab is currently investigating other reptiles that feed intermittently, including lizards and crocodiles. American alligators, for instance, exhibited a two- to threefold increase in metabolism during digestion. But, Hicks added, "So far, we haven't seen cardiovascular remodeling."
Nevertheless, hearts are known for their ability to adapt to the physiological demands of their owners. Human athletes, for example, often develop cardiac hypertrophy in response to vigorous training routines. Benefits of the condition include lowered heart rates and improved blood circulation.
The difficulty, Hicks said, is in understanding the mechanisms that lead to heart remodeling in humans and other mammals. Such investigations involve complex and highly invasive surgical procedures that could easily result in death.
Hicks and his colleagues propose the Burmese python as an ideal investigative model instead.
August Krogh, the 20th-century Danish physiologist, once wrote, "For a large number of problems there will be some animal of choice, or a few such animals, on which it can be most conveniently studied."
Krogh's approach has been a guiding principle for comparative physiology ever since.
Hicks said if we want to better understand how the human heart is able to remodel itself, we should look no further than the Burmese python.
After all, the reptile can grow its heart in the time it takes to eat its lunch
New research shows that when the reptiles swallow whole rats, birds, and other prey, the pythons' hearts temporarily grow bigger.Scientists in California say the snakes experience a 40 percent increase in heart muscle mass within 48 hours of feeding. The change enables the pythons to meet the metabolic demands of digesting a meal.
What's more, the process is fully reversible, with the snakes' hearts shrinking back to their original size once feeding ends.
Pythons can offer new insights to understanding heart growth in other species, including humans, according to researchers behind the discovery, which is reported in the current issue of the science journal Nature.
One of the world's largest snakes, the Burmese python can grow as long as 25 feet (7.6 meters) and weigh as much as 200 pounds (90 kilograms). Native to Southeast Asia, it preys on mammals, birds, and other animals, which the reptile swallows whole. But python meals are few and far between.
"These animals have a remarkable ability to shut down their metabolism between meals," said James Hicks, a professor of ecology and evolutionary biology at the University of California, Irvine.
"We currently have 1.5-kilogram [3.3-pound] pythons in the lab that have not eaten for three months and have only lost one to ten grams [four to thirty-five hundredths of an ounce] of weight," noted Hicks, who is also the study's lead author.
But when these reptiles do feed, Hicks added, they often tackle prey that is 50 to 100 percent the size of their own body mass. Such meals require a considerable digestive effort.
"Some investigators have reported as much as a 44-fold increase in metabolism during digestion," Hicks said.
Metabolic Demands
Hicks and his colleagues investigated how Burmese pythons meet the metabolic demands of digestion.
They found that oxygen consumption rose sevenfold in lab pythons after feeding. This was accompanied by an extraordinarily rapid growth in heart size. The snakes' heart ventricle muscle mass (ventricles are the heart's pumping chambers) increased 40 percent in just two days.
The study team was able to link this sudden growth to increased production of a cardiac protein. The protein is associated with cells that enlarge the heart and boost its pumping capacity, a condition known as cardiac hypertrophy.
The researchers say feeding-induced cardiac hypertrophy likely explains why Burmese pythons pump 50 percent more blood per heartbeat while quietly digesting a meal than when slithering at full speed.
Previous studies point to why python hearts need to go into overdrive when these animals digest food. Researchers report livers growing to three times their normal size, intestines doubling in mass, and pancreatic enzyme activity increasing threefold. Such changes within the snake significantly raise the demand for oxygenated blood.
Stephen Secor, a biologist at the University of Alabama in Birmingham, is among those to have studied digestion in pythons. While most carnivores are able chew, tear up, or crush their prey first, snakes "swallow only intact prey and must delegate to the stomach the whole job of breaking [it] down," Secor said.
Yet once a python has finished its meal, its heart quickly returns to its usual size.
Heart Remodeling
Hicks, the University of California ecologist and evolutionary biologist, said that by quickly remodeling their hearts depending on whether they are feeding or fasting, Burmese pythons are able to match their metabolism to their bodily needs.
Hicks said he is unaware of any other animal that is able to do this with such speed.
His lab is currently investigating other reptiles that feed intermittently, including lizards and crocodiles. American alligators, for instance, exhibited a two- to threefold increase in metabolism during digestion. But, Hicks added, "So far, we haven't seen cardiovascular remodeling."
Nevertheless, hearts are known for their ability to adapt to the physiological demands of their owners. Human athletes, for example, often develop cardiac hypertrophy in response to vigorous training routines. Benefits of the condition include lowered heart rates and improved blood circulation.
The difficulty, Hicks said, is in understanding the mechanisms that lead to heart remodeling in humans and other mammals. Such investigations involve complex and highly invasive surgical procedures that could easily result in death.
Hicks and his colleagues propose the Burmese python as an ideal investigative model instead.
August Krogh, the 20th-century Danish physiologist, once wrote, "For a large number of problems there will be some animal of choice, or a few such animals, on which it can be most conveniently studied."
Krogh's approach has been a guiding principle for comparative physiology ever since.
Hicks said if we want to better understand how the human heart is able to remodel itself, we should look no further than the Burmese python.
After all, the reptile can grow its heart in the time it takes to eat its lunch
Global warming not linked to sun
Cyclical changes in the sun's energy output are not responsible for Earth's recent warming, a new study asserts.
The findings put the blame for climate change squarely on human-created carbon dioxide and other greenhouse gases, reinforcing the beliefs of most climate scientists.
The sun's output waxes and wanes due to a variety of mechanisms. Its power rose during much of the 20th century, but it has declined. “Up until 1985, you could argue that the sun was (trending) in a direction that could have contributed to Earth's rising temperatures,” said study author A. Mike Lockwood of the University of Southampton in Britain.
Two decades ago, “it did a U-turn. If the sun had been warming the Earth, that should have come to an end, and we should have seen temperatures start to go the other way,” Lockwood said.
Yet temperatures have continued to climb since that date, making a strong solar role in warming appear unlikely.
read more >
Global Warring: Climate Change Could Be The Root Of Armed Conflicts
Source - www.sciencedaily.com Tuesday, July 10, 2007
Climate change, and the resulting shortage of ecological resources, could be to blame for armed conflicts in the future, according to David Zhang from the University of Hong Kong and colleagues. Their research, which highlights how temperature fluctuations and reduced agricultural production explain warfare frequency in eastern China in the past, has been published online in Springer’s journal Human Ecology.
Zhang and his team looked at the impact of climate change on warfare frequency over the last millennium in eastern China. The agricultural production in the region supports the majority of the Chinese population. The authors reviewed warfare data from 899 wars in eastern China between 1000 and 1911, documented in the Tabulation of Wars in Ancient China. They cross-referenced these data with Northern Hemispheric climate series temperature data for the same period.
They found that warfare frequency in eastern China, and the southern part in particular, significantly correlated with temperature oscillations. Almost all peaks of warfare and dynastic changes coincided with cold phases.
Temperature fluctuations directly impact agriculture and horticulture and, in societies with limited technology such as pre-industrial China, cooling temperatures hugely impact the availability of crops and herds. In times of such ecological stress, warfare could be the ultimate means of redistributing resources, according to Zhang and his team.
The authors conclude that "it was the oscillations of agricultural production brought by long-term climate change that drove China’s historical war-peace cycles." They recommend that researchers consider climate change part of the equation when they consider the reasons behind wars in our history.
Looking to the future and applying their findings, Zhang and colleagues suggest that shortages of essential resources, such as fresh water, agricultural land, energy sources and minerals may trigger more armed conflicts among human societies.
The findings put the blame for climate change squarely on human-created carbon dioxide and other greenhouse gases, reinforcing the beliefs of most climate scientists.
The sun's output waxes and wanes due to a variety of mechanisms. Its power rose during much of the 20th century, but it has declined. “Up until 1985, you could argue that the sun was (trending) in a direction that could have contributed to Earth's rising temperatures,” said study author A. Mike Lockwood of the University of Southampton in Britain.
Two decades ago, “it did a U-turn. If the sun had been warming the Earth, that should have come to an end, and we should have seen temperatures start to go the other way,” Lockwood said.
Yet temperatures have continued to climb since that date, making a strong solar role in warming appear unlikely.
read more >
Global Warring: Climate Change Could Be The Root Of Armed Conflicts
Source - www.sciencedaily.com Tuesday, July 10, 2007
Climate change, and the resulting shortage of ecological resources, could be to blame for armed conflicts in the future, according to David Zhang from the University of Hong Kong and colleagues. Their research, which highlights how temperature fluctuations and reduced agricultural production explain warfare frequency in eastern China in the past, has been published online in Springer’s journal Human Ecology.
Zhang and his team looked at the impact of climate change on warfare frequency over the last millennium in eastern China. The agricultural production in the region supports the majority of the Chinese population. The authors reviewed warfare data from 899 wars in eastern China between 1000 and 1911, documented in the Tabulation of Wars in Ancient China. They cross-referenced these data with Northern Hemispheric climate series temperature data for the same period.
They found that warfare frequency in eastern China, and the southern part in particular, significantly correlated with temperature oscillations. Almost all peaks of warfare and dynastic changes coincided with cold phases.
Temperature fluctuations directly impact agriculture and horticulture and, in societies with limited technology such as pre-industrial China, cooling temperatures hugely impact the availability of crops and herds. In times of such ecological stress, warfare could be the ultimate means of redistributing resources, according to Zhang and his team.
The authors conclude that "it was the oscillations of agricultural production brought by long-term climate change that drove China’s historical war-peace cycles." They recommend that researchers consider climate change part of the equation when they consider the reasons behind wars in our history.
Looking to the future and applying their findings, Zhang and colleagues suggest that shortages of essential resources, such as fresh water, agricultural land, energy sources and minerals may trigger more armed conflicts among human societies.
GLOBAL WARMING:Early warning signs
This map illustrates the local consequences of global warming.
FINGERPRINTS: Direct manifestations of a widespread and long-term trend toward warmer global temperatures
Heat waves and periods of unusually warm weather
Ocean warming, sea-level rise and coastal flooding
Glaciers melting
Arctic and Antarctic warming
HARBINGERS: Events that foreshadow the types of impacts likely to become more frequent and widespread with continued warming.
Spreading disease
Earlier spring arrival
Plant and animal range shifts and population changes
Coral reef bleaching
Downpours, heavy snowfalls, and flooding
Droughts and fires
The map of early warning signs clearly illustrates the global nature of climate changes. In its 2001 assessment, the Intergovernmental Panel on Climate Change (IPCC) concluded that, ?an increasing body of observations gives a collective picture of a warming world and other changes in the climate system."
While North America and Europe—where the science is strongest—exhibit the highest density of indicators, scientists have made a great effort in recent years to document the early impacts of global warming on other continents. Our map update reflects this emerging knowledge from all parts of the world.
Although factors other than climate may have intensified the severity of some of the events on the map, scientists predict such problems will increase if emissions of heat-trapping gases are not brought under control.
You can purchase a copy of the map as a 3 feet by 2 feet display poster. Please note that the hard-copy versions of the map do not contain the recently added map points (points 90 - 156).-->
The following organizations produced GLOBAL WARMING: Early Warning Signs:
Environmental DefenseNatural Resources Defense CouncilSierra ClubUnion of Concerned Scientists
U.S. Public Interest Research GroupWorld Resources InstituteWorld Wildlife Fund
FINGERPRINTS: Direct manifestations of a widespread and long-term trend toward warmer global temperatures
Heat waves and periods of unusually warm weather
Ocean warming, sea-level rise and coastal flooding
Glaciers melting
Arctic and Antarctic warming
HARBINGERS: Events that foreshadow the types of impacts likely to become more frequent and widespread with continued warming.
Spreading disease
Earlier spring arrival
Plant and animal range shifts and population changes
Coral reef bleaching
Downpours, heavy snowfalls, and flooding
Droughts and fires
The map of early warning signs clearly illustrates the global nature of climate changes. In its 2001 assessment, the Intergovernmental Panel on Climate Change (IPCC) concluded that, ?an increasing body of observations gives a collective picture of a warming world and other changes in the climate system."
While North America and Europe—where the science is strongest—exhibit the highest density of indicators, scientists have made a great effort in recent years to document the early impacts of global warming on other continents. Our map update reflects this emerging knowledge from all parts of the world.
Although factors other than climate may have intensified the severity of some of the events on the map, scientists predict such problems will increase if emissions of heat-trapping gases are not brought under control.
You can purchase a copy of the map as a 3 feet by 2 feet display poster. Please note that the hard-copy versions of the map do not contain the recently added map points (points 90 - 156).-->
The following organizations produced GLOBAL WARMING: Early Warning Signs:
Environmental DefenseNatural Resources Defense CouncilSierra ClubUnion of Concerned Scientists
U.S. Public Interest Research GroupWorld Resources InstituteWorld Wildlife Fund
Scientists: Global warming has already changed oceans
In Washington state, oysters in some areas haven't reproduced for four years, and preliminary evidence suggests that the increasing acidity of the ocean could be the cause. In the Gulf of Mexico, falling oxygen levels in the water have forced shrimp to migrate elsewhere. Though two marine-derived drugs, one for treating cancer and the other for pain control, are on the market and 25 others are under development, the fungus growing on seaweed, bacteria in deep sea mud and sea fans...
Global warming: Want to see Northwest impacts? Just look around
Living in a corner of America powered, irrigated and inspired by water, we ought to treat Tuesday's report released by the White House, Global Climate Change Impacts in the United States, as a wake-up call and cold shower.
"We are the alpha and the omega of global warming," said Rep. Jay Inslee, D-Wash., who helped write a flawed -- but needed -- bill to change national energy policy. It's pending in the House.
Want to know how climate change is changing America? Read the report. Want its bottom line: "Global warming is unequivocal and primarily human-induced." Changes "are expected to increase."
Want to see impacts on the Northwest? Just look around, something that global-warming skeptics resolutely refuse to do.
Global warming is shrinking the winter snowpack. A smaller snowpack means reduction in the runoff that sustains our river flows, makes the desert bloom, allows salmon to reach and return from the ocean, and powers the world's greatest hydroelectric system.
The consequences don't end when our rivers reach salt water.
"Climate change and ocean acidification are already having major impacts on Washington: Our $100 million shellfish industry is in crisis after four years of oyster reproductive failure from ocean acidification," said Sen. Maria Cantwell, D-Wash.
If oyster beds are in peril, so are salmon-spawning streams. One third of current habitat for Northwest salmon and other cold-water fish will be lost in this century, or so finds the report.
What critters will most likely be conflicted? Us. Just look at the legal and political battles that have broken out in years of low stream flow on the Columbia, Snake and Klamath rivers.
Irrigators in the Klamath Basin cried one season that they lacked water to grow crops. A year later, the Bush administration tipped scales in irrigators' favor, and caused a massive salmon kill in a warm, low-flowing Klamath River.
Climate change is going to require a lot of hard thinking, which better begin right now.
"The worst response for all the user/sectors is, given the certainty of intensified conflict, to hunker down to defend 'my slice of the shrinking pie,'" opined Pat Ford of Save Our Wild Salmon.
"Global warming's accumulated impacts on our waters are best viewed as a vise, steadily tightening on all water users regardless of past ideology, who's right, and past power relations. A shift is needed, away from old Western 'water is for fighting' lens, to a shared solutions, shared sacrifice, shared shortage lens."
The Northwest shares climate impacts with its neighbors in the West.
Alaska has warmed at more than twice the rate of the rest of the country, its annual average temperature up 3.4 degrees Fahrenheit: Winters have warmed 6.3 degrees.One result is the largest outbreak of tree-killing spruce beetles in the world. In the report's words, rising temperatures "allowed the beetle to survive the winter and to complete its life cycle in half the usual time."
The same has happened with the pine bark beetle in Canada. It has killed forests over a Sweden-sized area of British Columbia, has crossed the Continental Divide and threatens to munch its way across the Great White North.
In our inland West, more than 50 percent of whitebark pine forests in the Northern Rockies has been lost since 1970 -- largely due to beetle infestations. The whitebark pine anchors the soil at high elevations. Its fatty cones are a key pre-hibernation food for grizzly bears.
Hiking in the Wind River Mountains of Wyoming last summer, retired Forest Service scientist Dr. Jesse Logan showed us tiny holes bored by beetles.
"These trees are dead," he said. "They don't know it yet, though. I guess they are zombie trees."
A few hours earlier, down in a park at Dubois, oil industry workers told us that global warming was a "hoax." But the hoax is killing the forests above them and melting glaciers that sustain flow of the Wind River.
The global-warming report, and its White House release, is welcome on one front: As science struggles to keep up with impacts of global warming, politics is at last trying to keep up with science.
"Finally, the U.S. government is leveling with the American people about the threat we all face," said Dr. Jeffrey Short, a former government scientist who now works for Oceana.
The U.S. House of Representatives will soon vote on what's known as the Waxman-Markey Bill. It makes concessions to polluters. It sets what Denis Hayes of The Bullitt Foundation calls "a wimpy 17 percent reduction in carbon emissions" as a goal for 2020.
Yet, Hayes is urging lawmakers to hold their noses and vote for the bill -- to give the Obama administration credibility and needed momentum in the global effort to curb global warming.
"Climate legislation has to pass a Senate in which the oil, coal and electric utility industries wield fearsome power," Hayes said.
Some will deny this. Such is their right. It's dangerous, however, to stick your head in the sand when sea levels are rising.
"We are the alpha and the omega of global warming," said Rep. Jay Inslee, D-Wash., who helped write a flawed -- but needed -- bill to change national energy policy. It's pending in the House.
Want to know how climate change is changing America? Read the report. Want its bottom line: "Global warming is unequivocal and primarily human-induced." Changes "are expected to increase."
Want to see impacts on the Northwest? Just look around, something that global-warming skeptics resolutely refuse to do.
Global warming is shrinking the winter snowpack. A smaller snowpack means reduction in the runoff that sustains our river flows, makes the desert bloom, allows salmon to reach and return from the ocean, and powers the world's greatest hydroelectric system.
The consequences don't end when our rivers reach salt water.
"Climate change and ocean acidification are already having major impacts on Washington: Our $100 million shellfish industry is in crisis after four years of oyster reproductive failure from ocean acidification," said Sen. Maria Cantwell, D-Wash.
If oyster beds are in peril, so are salmon-spawning streams. One third of current habitat for Northwest salmon and other cold-water fish will be lost in this century, or so finds the report.
What critters will most likely be conflicted? Us. Just look at the legal and political battles that have broken out in years of low stream flow on the Columbia, Snake and Klamath rivers.
Irrigators in the Klamath Basin cried one season that they lacked water to grow crops. A year later, the Bush administration tipped scales in irrigators' favor, and caused a massive salmon kill in a warm, low-flowing Klamath River.
Climate change is going to require a lot of hard thinking, which better begin right now.
"The worst response for all the user/sectors is, given the certainty of intensified conflict, to hunker down to defend 'my slice of the shrinking pie,'" opined Pat Ford of Save Our Wild Salmon.
"Global warming's accumulated impacts on our waters are best viewed as a vise, steadily tightening on all water users regardless of past ideology, who's right, and past power relations. A shift is needed, away from old Western 'water is for fighting' lens, to a shared solutions, shared sacrifice, shared shortage lens."
The Northwest shares climate impacts with its neighbors in the West.
Alaska has warmed at more than twice the rate of the rest of the country, its annual average temperature up 3.4 degrees Fahrenheit: Winters have warmed 6.3 degrees.One result is the largest outbreak of tree-killing spruce beetles in the world. In the report's words, rising temperatures "allowed the beetle to survive the winter and to complete its life cycle in half the usual time."
The same has happened with the pine bark beetle in Canada. It has killed forests over a Sweden-sized area of British Columbia, has crossed the Continental Divide and threatens to munch its way across the Great White North.
In our inland West, more than 50 percent of whitebark pine forests in the Northern Rockies has been lost since 1970 -- largely due to beetle infestations. The whitebark pine anchors the soil at high elevations. Its fatty cones are a key pre-hibernation food for grizzly bears.
Hiking in the Wind River Mountains of Wyoming last summer, retired Forest Service scientist Dr. Jesse Logan showed us tiny holes bored by beetles.
"These trees are dead," he said. "They don't know it yet, though. I guess they are zombie trees."
A few hours earlier, down in a park at Dubois, oil industry workers told us that global warming was a "hoax." But the hoax is killing the forests above them and melting glaciers that sustain flow of the Wind River.
The global-warming report, and its White House release, is welcome on one front: As science struggles to keep up with impacts of global warming, politics is at last trying to keep up with science.
"Finally, the U.S. government is leveling with the American people about the threat we all face," said Dr. Jeffrey Short, a former government scientist who now works for Oceana.
The U.S. House of Representatives will soon vote on what's known as the Waxman-Markey Bill. It makes concessions to polluters. It sets what Denis Hayes of The Bullitt Foundation calls "a wimpy 17 percent reduction in carbon emissions" as a goal for 2020.
Yet, Hayes is urging lawmakers to hold their noses and vote for the bill -- to give the Obama administration credibility and needed momentum in the global effort to curb global warming.
"Climate legislation has to pass a Senate in which the oil, coal and electric utility industries wield fearsome power," Hayes said.
Some will deny this. Such is their right. It's dangerous, however, to stick your head in the sand when sea levels are rising.
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