Diagnosing sleep apnea -- a chronic condition that causes teen-agers to stop breathing during sleep -- is difficult and often means staying at an overnight sleep lab. A new test can spot with problem with simple X-rays, by checking the position of the tongue and hyoid bone. If the bone sits lower, patients are more likely to have the condition. In a recent study, the X-rays correctly identified 70 percent of teens with sleep apnea.
Being a teenager is tough these days, but it's especially tough if you're always tired. Now a simple X-ray taken at your children's orthodontist could hold the key to helping them sleep better.
Sixteen-year-old Andrew Dudash would come home from school each day and go straight to bed. "I actually got a detention in school for sleeping during a class," he says.
Doctors diagnosed him with sleep apnea, a chronic condition that causes him to stop breathing during sleep. Diagnosing the condition is difficult and often means staying at an overnight sleep lab. But orthodontist Mark Hans wants to make that diagnosis easier. He's studying whether the same X-rays teens get before getting braces will help determine if they're at risk for sleep apnea.
"We're trying to give the sleep doctor a better chance of examining the right patients for this condition," says Dr. Hans, of Case Western Reserve University School of Dental Medicine in Cleveland.
Dr. Hans looks at the position of the tongue and hyoid bone. If the bone sits higher, patients are not at risk for sleep apnea. If it falls lower, they are more likely to have the condition.
In a recent study, the X-rays correctly identified 70 percent of teens with sleep apnea. Dr. Hans says, "When you identify chronic illness early and treat it early, you really prevent more long-term problems."
Case School of Medicine pediatric pulmonologist and sleep specialist Carol Rosen, says the X-rays would help. "This would add another feature that we would look for in our evaluation." So teens like Dudash can get the treatment they need.
"There's definitely a difference in my sleep because I'm not waking up much during the night," Dudash says. And his sleep is not something he's willing to gamble on.
Dr. Hans says there's no disadvantage to performing the X-ray other than a minimal dose of radiation, which is equivalent to a day in the sun. He says most insurance covers the X-rays, which cost about $100. A sleep lab evaluation could cost thousands.
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BACKGROUND: Researchers at Case Western Reserve University in Cleveland, Ohio, have identified two key factors in sleep apnea in teenagers. They used radiography (an imaging technique used by orthodontists) to study a group of teens to determine if they were likely to suffer from the condition. The technique will be used for earlier diagnosis for sleep apnea in teens before they become adults.
THE STUDY: The investigators studied the case histories of 590 patients between 7 and 8 years of age attending the orthodontic clinic at Case Dental School. Sixty of these patients -- a group least at risk and a group most at risk for sleep apnea -- underwent unattended in-home sleep monitoring.
WHAT IS SLEEP APNEA: Sleep apnea is a temporary suspension of breathing during sleep, which can have potentially serious consequences. People with sleep apnea can stop breathing for 10 to 30 seconds at a time, as many as 400 times a night. Most sleep apneas are the result of something blocking the passage of windpipe of the throat that brings air into the body. The tongue, tonsils, or uvula (the little piece of flesh that hangs down in the back of the throat) can all sometimes produce blockage, as can severe obesity: excess fat can block the airway. Some 12 million Americans suffer from sleep apnea, but men and those over 40 years of age are more likely to have the condition. Risk factors include heavy snoring, excess weight, high blood pressure, and any physical abnormality in the nose or throat.
WHAT ARE X-RAYS: X-rays are light waves.
The only difference between X-rays and the light that we see is that the X-rays have a higher energy level, and a shorter wavelength, making them undetectable to the human eye. Because they have so much energy, the particles that make up light, called photons, in X-rays can pass through most materials. It all depends on the size of the atoms that make up the material; larger atoms absorb X-ray photons. But smaller atoms do not, and the X-rays pass right through.
The soft tissue in the body is made of smaller atoms and doesn't absorb X-rays very well, but calcium atoms in the bones are much larger and do absorb X-rays. A camera on the other side of the patient records the patterns of X-ray light passing through the patient's body.
It's the same basic technology as that used in an ordinary camera, but X-ray light, instead of visible light, sets off the chemical reaction on the photographic plate.
Tuesday, July 7, 2009
How Can The World's Fisheries Be Sustainable?
According to the most recent report on the status of the world's fisheries by the United Nations Food and Agriculture Organization, fisheries supply at least 15% of the animal protein consumed by humans, provide direct and indirect employment for nearly 200 million people worldwide and generate $US85 billion annually. This same report indicates that 28% of the world's fisheries stocks are currently being overexploited or have collapsed and 52% are fully exploited.
A new study published in PLoS Biology provides the first global evaluation of how management practices influence fisheries' sustainability. The study assessed the effectiveness of the world's fisheries management regimes using evaluations from nearly 1,200 fisheries experts, analyzing these in combination with data on the sustainability of fisheries catches. The results indicate that most fisheries management regimes are lagging far behind standards set by international organizations, and that the conversion of scientific advice into policy, through a participatory and transparent process, plays the most critical role in determining the sustainability of fisheries.
"The world's fisheries are one of the most important natural assets to humankind," says lead author Camilo Mora, a Colombian researcher at Dalhousie University and the University of California San Diego. "Unfortunately, our use of the world's fisheries has been excessive and has led to the decline or collapse of many stocks."
"The consequences of overexploiting the world's fisheries are a concern not only for food security and socio-economic development but for ocean ecosystems," says Boris Worm, a professor at Dalhousie University and co-author of the paper. "We now recognize that overfishing can also lead to the erosion of biodiversity and ecosystem productivity."
"The different socioeconomic and ecological consequences associated with declining fish stocks are an international concern and several initiatives have been put forward to ensure that countries improve the way they use their marine resources," explains Mora. "Some of these initiatives include the United Nations Code of Conduct for Responsible Fisheries, the Convention on Biological Diversity, and the Millennium Ecosystem Assessment. Although these initiatives have been endorsed by most governments, a global assessment on the extent to which these ideals are actually implemented and effective remains lacking."
Mora and his colleagues analyzed a set of attributes upon which country-level fisheries could be evaluated. They pinpointed six parameters, including the scientific quality of management recommendations, the transparency of converting recommendations into policy, the enforcement of policies, the influence of subsidies, fishing effort, and the extent of fishing by foreign entities.
To quantify those attributes the researchers developed a questionnaire designed to elicit worst- to best-case answers. The survey was translated into five languages and distributed to over 13,000 fisheries experts around the world. Nearly 1,200 evaluations were used in the study. The responses of the surveyed experts were compared to, and found to be in accordance with, empirical data, supporting the validity of the data obtained in the study.
The results of this global survey showed that 7% of all coastal states carry out rigorous scientific assessment for the generation of management policies, 1.4% also have a participatory and transparent process to convert scientific recommendations into policy, and less than 1% also implement mechanisms to ensure the compliance with regulations. No one country was additionally free of the effects of excess fishing capacity, subsidies or access to foreign fishing.
"Perhaps the most striking result of our survey was that not a single country in the world was consistently good with respect to all these management attributes. So which countries are doing well and which are not is a question whose answer depends on the specific attribute you are looking at," says Mora.
The results of the study show that wealthier countries, though they have predominantly better science and enforcement capabilities, face the negative repercussions of excessive subsidies and larger fishing capacity, which have resulted largely from increased modernization of national fleets. In contrast, poorer countries largely lacked robust science and enforcement capabilities and although these nations have less fishing capacity nationally, they disproportionally sold fishing rights to nations that did. The study showed that in 33% of the coastal states classified as low-income (commonly countries in Africa and Oceania) most fishing is carried out by foreign fleets from either the European Union, South Korea, Japan, China, Taiwan or the United States.
The only attribute in which poorer and wealthier countries overlapped significantly was their limited ability to convert scientific recommendations into policy. The mechanism for this pattern, however, was different. Poor countries reportedly struggle with the effects of corruption while wealthier countries often encounter more political or economical pressures.
For the second part of the study, Mora and his colleagues combined the database on management effectiveness with a recently developed index to assess the probability that the catch of a particular country is sustainable or not. This part of the study showed that out of several attributes analysed, the transparency with which scientific recommendations are turned into policy plays the strongest role in the fate of fisheries sustainability.
"Transparent policy-making is at the centre of the entire process," explains co-author Marta Coll, at the Institut de Ciènces del Mar in Spain. "If this is heavily influenced by political pressures or corruption, it is unlikely that good scientific advice will ever be translated into proper regulations. Similarly, authoritarianism in this process is likely to reduce compliance with the resulting policies."
"This study provided us with a look at both sides of the coin," says Andrew Rosenberg at the University of New Hampshire, who was not involved in the study. "On one hand, it reminds us of the difficult challenges facing fisheries management globally in protecting critical natural resources from overexploitation. On the other hand it delivers a message of hope that when policy-making is transparent, participatory, and based on science, things can improve."
Funding to CM, RAM, and BW was provided by the Sloan Foundation through the Future of Marine Animal Populations Project. KJG holds a Royal Society-Wolfson Research Merit Award. Funding to RUS was provided by the Pew Fellowship for Marine Conservation. Funding to DZ, RUS, and RW was provided by the Pew Charitable Trust, Philadelphia through the Sea Around Us Project. Funding to MC was provided by the European Community's Seventh Framework Programme FP7/2007-2013 under grant agreement #GA-2008-219265 for the implementation of ECOFUN Project. The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.
A new study published in PLoS Biology provides the first global evaluation of how management practices influence fisheries' sustainability. The study assessed the effectiveness of the world's fisheries management regimes using evaluations from nearly 1,200 fisheries experts, analyzing these in combination with data on the sustainability of fisheries catches. The results indicate that most fisheries management regimes are lagging far behind standards set by international organizations, and that the conversion of scientific advice into policy, through a participatory and transparent process, plays the most critical role in determining the sustainability of fisheries.
"The world's fisheries are one of the most important natural assets to humankind," says lead author Camilo Mora, a Colombian researcher at Dalhousie University and the University of California San Diego. "Unfortunately, our use of the world's fisheries has been excessive and has led to the decline or collapse of many stocks."
"The consequences of overexploiting the world's fisheries are a concern not only for food security and socio-economic development but for ocean ecosystems," says Boris Worm, a professor at Dalhousie University and co-author of the paper. "We now recognize that overfishing can also lead to the erosion of biodiversity and ecosystem productivity."
"The different socioeconomic and ecological consequences associated with declining fish stocks are an international concern and several initiatives have been put forward to ensure that countries improve the way they use their marine resources," explains Mora. "Some of these initiatives include the United Nations Code of Conduct for Responsible Fisheries, the Convention on Biological Diversity, and the Millennium Ecosystem Assessment. Although these initiatives have been endorsed by most governments, a global assessment on the extent to which these ideals are actually implemented and effective remains lacking."
Mora and his colleagues analyzed a set of attributes upon which country-level fisheries could be evaluated. They pinpointed six parameters, including the scientific quality of management recommendations, the transparency of converting recommendations into policy, the enforcement of policies, the influence of subsidies, fishing effort, and the extent of fishing by foreign entities.
To quantify those attributes the researchers developed a questionnaire designed to elicit worst- to best-case answers. The survey was translated into five languages and distributed to over 13,000 fisheries experts around the world. Nearly 1,200 evaluations were used in the study. The responses of the surveyed experts were compared to, and found to be in accordance with, empirical data, supporting the validity of the data obtained in the study.
The results of this global survey showed that 7% of all coastal states carry out rigorous scientific assessment for the generation of management policies, 1.4% also have a participatory and transparent process to convert scientific recommendations into policy, and less than 1% also implement mechanisms to ensure the compliance with regulations. No one country was additionally free of the effects of excess fishing capacity, subsidies or access to foreign fishing.
"Perhaps the most striking result of our survey was that not a single country in the world was consistently good with respect to all these management attributes. So which countries are doing well and which are not is a question whose answer depends on the specific attribute you are looking at," says Mora.
The results of the study show that wealthier countries, though they have predominantly better science and enforcement capabilities, face the negative repercussions of excessive subsidies and larger fishing capacity, which have resulted largely from increased modernization of national fleets. In contrast, poorer countries largely lacked robust science and enforcement capabilities and although these nations have less fishing capacity nationally, they disproportionally sold fishing rights to nations that did. The study showed that in 33% of the coastal states classified as low-income (commonly countries in Africa and Oceania) most fishing is carried out by foreign fleets from either the European Union, South Korea, Japan, China, Taiwan or the United States.
The only attribute in which poorer and wealthier countries overlapped significantly was their limited ability to convert scientific recommendations into policy. The mechanism for this pattern, however, was different. Poor countries reportedly struggle with the effects of corruption while wealthier countries often encounter more political or economical pressures.
For the second part of the study, Mora and his colleagues combined the database on management effectiveness with a recently developed index to assess the probability that the catch of a particular country is sustainable or not. This part of the study showed that out of several attributes analysed, the transparency with which scientific recommendations are turned into policy plays the strongest role in the fate of fisheries sustainability.
"Transparent policy-making is at the centre of the entire process," explains co-author Marta Coll, at the Institut de Ciènces del Mar in Spain. "If this is heavily influenced by political pressures or corruption, it is unlikely that good scientific advice will ever be translated into proper regulations. Similarly, authoritarianism in this process is likely to reduce compliance with the resulting policies."
"This study provided us with a look at both sides of the coin," says Andrew Rosenberg at the University of New Hampshire, who was not involved in the study. "On one hand, it reminds us of the difficult challenges facing fisheries management globally in protecting critical natural resources from overexploitation. On the other hand it delivers a message of hope that when policy-making is transparent, participatory, and based on science, things can improve."
Funding to CM, RAM, and BW was provided by the Sloan Foundation through the Future of Marine Animal Populations Project. KJG holds a Royal Society-Wolfson Research Merit Award. Funding to RUS was provided by the Pew Fellowship for Marine Conservation. Funding to DZ, RUS, and RW was provided by the Pew Charitable Trust, Philadelphia through the Sea Around Us Project. Funding to MC was provided by the European Community's Seventh Framework Programme FP7/2007-2013 under grant agreement #GA-2008-219265 for the implementation of ECOFUN Project. The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.
Close Relationship Between Past Warming And Sea-level Rise
A team from the National Oceanography Centre, Southampton (NOCS), along with colleagues from Tübingen (Germany) and Bristol presents a novel continuous reconstruction of sea level fluctuations over the last 520 thousand years. Comparison of this record with data on global climate and carbon dioxide (CO2) levels from Antarctic ice cores suggests that even stabilisation at today's CO2 levels may commit us to sea-level rise over the next couple of millennia, to a level much higher than long-term projections from the Fourth Assessment Report of the Intergovernmental Panel on Climate Change (IPCC).
Little is known about the total amount of possible sea-level rise in equilibrium with a given amount of global warming. This is because the melting of ice sheets is slow, even when temperature rises rapidly. As a consequence, current predictions of sea-level rise for the next century consider only the amount of ice sheet melt that will occur until that time. The total amount of ice sheet melting that will occur over millennia, given the current climate trends, remains poorly understood.
The new record reveals a systematic equilibrium relationship between global temperature and CO2 concentrations and sea-level changes over the last five glacial cycles. Projection of this relationship to today's CO2 concentrations results in a sea-level at 25 (±5) metres above the present. This is in close agreement with independent sea-level data from the Middle Pliocene epoch, 3-3.5 million years ago, when atmospheric CO2 concentrations were similar to the present-day value. This suggests that the identified relationship accurately records the fundamental long-term equilibrium behaviour of the climate system over the last 3.5 Million years.
Lead author Professor Eelco Rohling of the University of Southampton's School of Ocean and Earth Science based at NOCS, said: "Let's assume that our observed natural relationship between CO2 and temperature, and sea level, offers a reasonable 'model' for a future with sustained global warming. Then our result gives a statistically sound expectation of a potential total long-term sea-level rise. Even if we would curb all CO2 emissions today, and stabilise at the modern level (387 parts per million by volume), then our natural relationship suggests that sea level would continue to rise to about 25 m above the present. That is, it would rise to a level similar to that measured for the Middle Pliocene."
Project partners Professor Michal Kucera (University of Tübingen) and Dr Mark Siddall (University of Bristol), add: "We emphasise that such equilibration of sea level would take several thousands of years. But one still has to worry about the large difference between the inferred high equilibrium sea level and the level where sea level actually stands today. Recent geological history shows that times with similarly strong disequilibria commonly saw pulses of very rapid sea-level adjustment, at rates of 1-2 metres per century or higher."
The new study's projection of long-term sea-level change, based on the natural relationship of the last 0.5 to 3.5 million years, differs considerably from the IPCC's model-based long-term projection of +7 m. The discrepancy cannot be easily explained, and new work is needed to ensure that the 'gap is closed'.
The observed relationships from the recent geological past can form a test-bed or reality-check for models, to help them achieve improved future projections.
Little is known about the total amount of possible sea-level rise in equilibrium with a given amount of global warming. This is because the melting of ice sheets is slow, even when temperature rises rapidly. As a consequence, current predictions of sea-level rise for the next century consider only the amount of ice sheet melt that will occur until that time. The total amount of ice sheet melting that will occur over millennia, given the current climate trends, remains poorly understood.
The new record reveals a systematic equilibrium relationship between global temperature and CO2 concentrations and sea-level changes over the last five glacial cycles. Projection of this relationship to today's CO2 concentrations results in a sea-level at 25 (±5) metres above the present. This is in close agreement with independent sea-level data from the Middle Pliocene epoch, 3-3.5 million years ago, when atmospheric CO2 concentrations were similar to the present-day value. This suggests that the identified relationship accurately records the fundamental long-term equilibrium behaviour of the climate system over the last 3.5 Million years.
Lead author Professor Eelco Rohling of the University of Southampton's School of Ocean and Earth Science based at NOCS, said: "Let's assume that our observed natural relationship between CO2 and temperature, and sea level, offers a reasonable 'model' for a future with sustained global warming. Then our result gives a statistically sound expectation of a potential total long-term sea-level rise. Even if we would curb all CO2 emissions today, and stabilise at the modern level (387 parts per million by volume), then our natural relationship suggests that sea level would continue to rise to about 25 m above the present. That is, it would rise to a level similar to that measured for the Middle Pliocene."
Project partners Professor Michal Kucera (University of Tübingen) and Dr Mark Siddall (University of Bristol), add: "We emphasise that such equilibration of sea level would take several thousands of years. But one still has to worry about the large difference between the inferred high equilibrium sea level and the level where sea level actually stands today. Recent geological history shows that times with similarly strong disequilibria commonly saw pulses of very rapid sea-level adjustment, at rates of 1-2 metres per century or higher."
The new study's projection of long-term sea-level change, based on the natural relationship of the last 0.5 to 3.5 million years, differs considerably from the IPCC's model-based long-term projection of +7 m. The discrepancy cannot be easily explained, and new work is needed to ensure that the 'gap is closed'.
The observed relationships from the recent geological past can form a test-bed or reality-check for models, to help them achieve improved future projections.
Biogeochemists Map Out Carbon Dioxide Emissions In The U.S.
Biogeochemists located where the most carbon dioxide emissions occur in the U.S. using a new mapping system. With this program-available to anyone on the Web-researchers were able to extract information about carbon dioxide emissions by transforming data on local air pollution and combining it with geographic information systems (GIS) data to layer the emissions onto infrastructures at the Earth's surface. The map helps us learn more about carbon emissions and gives scientists a way to check the accuracy of satellite images.
The Environmental Protection Agency estimates emissions in the United States rose almost 15 percent between 1990 and 2006, and the number will continue to rise. Carbon dioxide is mainly responsible for the increase. A new high-tech map reveals the areas in the country most responsible for the carbon dioxide problem.
Carbon dioxide (CO2) is the most abundant greenhouse gas in our atmosphere. Its sources can be found almost everywhere -- from cars, to cows, to power plants -- but scientists are still trying to figure out which parts of the country are pumping out the most CO2.
In the past, CO2 levels have been calculated based on population, putting the Northeast at the top of the list. Now, a new map called Vulcan reveals for the first time where the top carbon dioxide producers are in the country. The answer surprised Kevin Gurney, Ph.D., a biogeochemist at Purdue University in West Lafayette, Ind.
"There are a lot more emissions in the Southeast than we previously thought, and a lot of that is because it's not necessarily associated with where people live directly, but actually where industry and activities are," said Dr. Gurney.
The high-resolution map shows 100 times more detail than ever before and zooms in to show greenhouse gas sources right down to factories, power plants and even roadways. An animated version of Vulcan reveals huge amounts of greenhouse gas gets blown toward the North Atlantic region.
"We've never had a map with this much detail and accuracy that everyone can view online," Dr. Gurney said.
The map helps scientists better visualize and target the areas where CO2 emissions are the highest and help those areas reduce their negative impact on Earth. It can be downloaded for free online from the Purdue University Vulcan Project Web site.
show background -->
ABOUT CARBON DIOXIDE: The concentration of carbon dioxide in the atmosphere has increased by about 30 percent since the beginning of the industrial revolution in the late 1800's. Most of this increase comes from using fossil fuel -- coal, oil and natural gas -- for energy, but approximately 25 percent of the carbon came from changes in land use, such as the clearing of forests and the cultivation of soils for food production. Natural sources of atmospheric carbon include gases emitted by volcanoes, and respiration of living things. We breathe in oxygen, and breathe out carbon dioxide.
ABOUT AIR POLLUTION: Air pollution is made up of many kinds of gases, droplets and particles that can remain suspended in the air. This makes the air dirty. The easiest way to visualize airborne particles (also called aerosols) is to exhale outside on a cold day and watch the fog come out of your mouth as water vapor forms into water droplets. The same thing happens in the atmosphere, but for different reasons. Under certain conditions individual molecules come together and form particles -- a chemical soup. In the city, air pollution may be caused by cars, buses and airplanes, as well as industry and construction. Ground-level ozone is created when engine and fuel gases already released into the air interact when sunlight hits them. Ozone levels increase in cities when the air is still, the sun is bright and the temperature is warm.
The Environmental Protection Agency estimates emissions in the United States rose almost 15 percent between 1990 and 2006, and the number will continue to rise. Carbon dioxide is mainly responsible for the increase. A new high-tech map reveals the areas in the country most responsible for the carbon dioxide problem.
Carbon dioxide (CO2) is the most abundant greenhouse gas in our atmosphere. Its sources can be found almost everywhere -- from cars, to cows, to power plants -- but scientists are still trying to figure out which parts of the country are pumping out the most CO2.
In the past, CO2 levels have been calculated based on population, putting the Northeast at the top of the list. Now, a new map called Vulcan reveals for the first time where the top carbon dioxide producers are in the country. The answer surprised Kevin Gurney, Ph.D., a biogeochemist at Purdue University in West Lafayette, Ind.
"There are a lot more emissions in the Southeast than we previously thought, and a lot of that is because it's not necessarily associated with where people live directly, but actually where industry and activities are," said Dr. Gurney.
The high-resolution map shows 100 times more detail than ever before and zooms in to show greenhouse gas sources right down to factories, power plants and even roadways. An animated version of Vulcan reveals huge amounts of greenhouse gas gets blown toward the North Atlantic region.
"We've never had a map with this much detail and accuracy that everyone can view online," Dr. Gurney said.
The map helps scientists better visualize and target the areas where CO2 emissions are the highest and help those areas reduce their negative impact on Earth. It can be downloaded for free online from the Purdue University Vulcan Project Web site.
show background -->
ABOUT CARBON DIOXIDE: The concentration of carbon dioxide in the atmosphere has increased by about 30 percent since the beginning of the industrial revolution in the late 1800's. Most of this increase comes from using fossil fuel -- coal, oil and natural gas -- for energy, but approximately 25 percent of the carbon came from changes in land use, such as the clearing of forests and the cultivation of soils for food production. Natural sources of atmospheric carbon include gases emitted by volcanoes, and respiration of living things. We breathe in oxygen, and breathe out carbon dioxide.
ABOUT AIR POLLUTION: Air pollution is made up of many kinds of gases, droplets and particles that can remain suspended in the air. This makes the air dirty. The easiest way to visualize airborne particles (also called aerosols) is to exhale outside on a cold day and watch the fog come out of your mouth as water vapor forms into water droplets. The same thing happens in the atmosphere, but for different reasons. Under certain conditions individual molecules come together and form particles -- a chemical soup. In the city, air pollution may be caused by cars, buses and airplanes, as well as industry and construction. Ground-level ozone is created when engine and fuel gases already released into the air interact when sunlight hits them. Ozone levels increase in cities when the air is still, the sun is bright and the temperature is warm.
Super-size Deposits Of Frozen Carbon In Arctic Could Worsen Climate Change
The vast amount of carbon stored in the arctic and boreal regions of the world is more than double that previously estimated, according to a study published this week.
The amount of carbon in frozen soils, sediments and river deltas (permafrost) raises new concerns over the role of the northern regions as future sources of greenhouse gases.
"We now estimate the deposits contain over 1.5 trillion tons of frozen carbon, about twice as much carbon as contained in the atmosphere", said Dr. Charles Tarnocai, Agriculture and Agri-Food Canada, Ottawa, and lead author.
Dr. Pep Canadell, Executive Director of the Global Carbon Project at CSIRO, Australia, and co-author of the study says that the existence of these super-sized deposits of frozen carbon means that any thawing of permafrost due to global warming may lead to significant emissions of the greenhouse gases carbon dioxide and methane.
Carbon deposits frozen thousands of years ago can easily break down when permafrost thaws releasing greenhouse gases to the atmosphere, according to another recent study by some of the same authors.
"Radioactive carbon dating shows that most of the carbon dioxide currently emitted by thawing soils in Alaska was formed and frozen thousands of years ago. The carbon dating demonstrates how easily carbon decomposes when soils thaw under warmer conditions," said Professor Ted Schuur, University of Florida and co-author of the paper.
The authors point out the large uncertainties surrounding the extent to which permafrost carbon thawing could further accelerate climate change.
"Permafrost carbon is a bit of a wildcard in the efforts to predict future climate change," said Dr Canadell. "All evidence to date shows that carbon in permafrost is likely to play a significant role in the 21st century climate given the large carbon deposits, the readiness of its organic matter to release greenhouse gases when thawed, and the fact that high latitudes will experience the largest increase in air temperature of all regions."
The amount of carbon in frozen soils, sediments and river deltas (permafrost) raises new concerns over the role of the northern regions as future sources of greenhouse gases.
"We now estimate the deposits contain over 1.5 trillion tons of frozen carbon, about twice as much carbon as contained in the atmosphere", said Dr. Charles Tarnocai, Agriculture and Agri-Food Canada, Ottawa, and lead author.
Dr. Pep Canadell, Executive Director of the Global Carbon Project at CSIRO, Australia, and co-author of the study says that the existence of these super-sized deposits of frozen carbon means that any thawing of permafrost due to global warming may lead to significant emissions of the greenhouse gases carbon dioxide and methane.
Carbon deposits frozen thousands of years ago can easily break down when permafrost thaws releasing greenhouse gases to the atmosphere, according to another recent study by some of the same authors.
"Radioactive carbon dating shows that most of the carbon dioxide currently emitted by thawing soils in Alaska was formed and frozen thousands of years ago. The carbon dating demonstrates how easily carbon decomposes when soils thaw under warmer conditions," said Professor Ted Schuur, University of Florida and co-author of the paper.
The authors point out the large uncertainties surrounding the extent to which permafrost carbon thawing could further accelerate climate change.
"Permafrost carbon is a bit of a wildcard in the efforts to predict future climate change," said Dr Canadell. "All evidence to date shows that carbon in permafrost is likely to play a significant role in the 21st century climate given the large carbon deposits, the readiness of its organic matter to release greenhouse gases when thawed, and the fact that high latitudes will experience the largest increase in air temperature of all regions."
Shilpa Shetty fights global warming
Shilpa Shetty is doing her bit to fight global warming. She has joined hands with Freeplay Energy India, a company that produces hand crank lanterns that generate electricity without using fuel. The actress' foundation will distribute these solar power- generated lamps for free to villages in India.
oneindiain121:http://entertainment.oneindia.in/bollywood/news/2009/shilpa-global-warming-070709.html
Buzz up!
Shilpa, who is currently in London, says, "The company has a patent technology called Crank. You don't need any kerosene or electricity or natural resources to light up these lamps. One just needs to wind up the crank system manually for one minute and you get 15 minutes of bright light. It's great for villages with no light. This way, we can save on pollution from burning fuels."The actress has tied up with the company to be her sole suppliers for these lamps, which cost roughly between Rs 1000-1500 each, "I have also incorporated solar power in some lamps which I will be giving out free through my organisation, the Shilpa Shetty Foundation to some villages that don't have electricity.”“It's been a cause that I feel for, besides it also promotes the cause of fighting global warming — by conserving energy. Since we are giving the lamps for free we are asking people to donate generously. Recently, I have given away my prize winnings from the show 10 Ka Dum show to the SSF. We need to do our bit for society as much as we can."
oneindiain121:http://entertainment.oneindia.in/bollywood/news/2009/shilpa-global-warming-070709.html
Buzz up!
Shilpa, who is currently in London, says, "The company has a patent technology called Crank. You don't need any kerosene or electricity or natural resources to light up these lamps. One just needs to wind up the crank system manually for one minute and you get 15 minutes of bright light. It's great for villages with no light. This way, we can save on pollution from burning fuels."The actress has tied up with the company to be her sole suppliers for these lamps, which cost roughly between Rs 1000-1500 each, "I have also incorporated solar power in some lamps which I will be giving out free through my organisation, the Shilpa Shetty Foundation to some villages that don't have electricity.”“It's been a cause that I feel for, besides it also promotes the cause of fighting global warming — by conserving energy. Since we are giving the lamps for free we are asking people to donate generously. Recently, I have given away my prize winnings from the show 10 Ka Dum show to the SSF. We need to do our bit for society as much as we can."
Screwing up environment not so great for economy, studies find 2
Let’s take a look at a few studies that have come out recently and see if we can find a common thread.
A West Virginia University researcher found that “coal mining costs Appalachians five times more in early deaths as the industry provides to the region in jobs, taxes and other economic benefits,” reports the Charleston Gazette.
The Mountain Association for Community Economic Development found that “the coal industry takes $115 million more from Kentucky’s state government annually in services and programs than it contributes in taxes,” reports the Lexington Herald-Leader.
A recent peer-reviewed paper in the journal Science found that areas of Brazil that cut down their rainforests to sell the wood or plant crops “do see a short-term boost in per-capita income, life expectancy, and literacy rates,” reports The Vine. “But once the trees are gone, those gains disappear, leaving deforested municipalities just as poor as those that preserved their forests.”
The International Fund for Animal Welfare found that “in 2008 whale-watching generated $2.1 billion of tourism revenue worldwide ... more than double the estimated $one billion generated by the industry in 1998,” reports Agence France-Presse. Said Australia Environment Minister Peter Garrett, “Whales are worth much more alive than dead.”
The University of Michigan found that “the Detroit Three automakers can become more profitable and slow the growth of their Japanese rivals if they simply meet tougher new government-mandated fuel economy standards,” reports the Detroit Free Press.
These are disparate areas of study and disparate conclusions. One thing they all have in common: an environment-degrading practice often defended as necessary to economic health is revealed, upon closer inspection, to be uneconomic. I wonder how many other allegedly economic environment-degrading practices would also be revealed uneconomic if examined with a fresh eye?
It’s almost like the economy is embedded in an environment, and degrading the latter ultimately degrades the former.
A West Virginia University researcher found that “coal mining costs Appalachians five times more in early deaths as the industry provides to the region in jobs, taxes and other economic benefits,” reports the Charleston Gazette.
The Mountain Association for Community Economic Development found that “the coal industry takes $115 million more from Kentucky’s state government annually in services and programs than it contributes in taxes,” reports the Lexington Herald-Leader.
A recent peer-reviewed paper in the journal Science found that areas of Brazil that cut down their rainforests to sell the wood or plant crops “do see a short-term boost in per-capita income, life expectancy, and literacy rates,” reports The Vine. “But once the trees are gone, those gains disappear, leaving deforested municipalities just as poor as those that preserved their forests.”
The International Fund for Animal Welfare found that “in 2008 whale-watching generated $2.1 billion of tourism revenue worldwide ... more than double the estimated $one billion generated by the industry in 1998,” reports Agence France-Presse. Said Australia Environment Minister Peter Garrett, “Whales are worth much more alive than dead.”
The University of Michigan found that “the Detroit Three automakers can become more profitable and slow the growth of their Japanese rivals if they simply meet tougher new government-mandated fuel economy standards,” reports the Detroit Free Press.
These are disparate areas of study and disparate conclusions. One thing they all have in common: an environment-degrading practice often defended as necessary to economic health is revealed, upon closer inspection, to be uneconomic. I wonder how many other allegedly economic environment-degrading practices would also be revealed uneconomic if examined with a fresh eye?
It’s almost like the economy is embedded in an environment, and degrading the latter ultimately degrades the former.
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