From hispanicallyspeakingnews.com:
As if the marine ecosystem wasn’t threatened enough by oil spills and excessive noise, the thinning of the ozone layer may be scarring the world’s whales from severe sunburn, experts said Wednesday.
A study of whales in the Mexican coast over the past few years, shows that the biggest mammals have blisters and other typical damage of exposure to the ultraviolet radiation. Simply put, whales are getting sunburned.
Whales seem to be particularly susceptible to sunburns, partly because they must spend extended periods of time on the surface of the ocean in order to breathe, socialize, and feed their calfs. Lacking fur or feathers, whales sunbathe naked.
Laura Martinez-Levasseur, the lead author of the study puts it: “Humans can put on clothes or sunglasses — whales can’t.”
Photographs were taken of the whales to examine any visible damages, and small skin samples were collected to analyze the state of their skin cells.
Her study confirmed suspicions first raised by one of her colleagues: The cetaceans are showing lesions associated with sun damage, and many of their skin samples revealed patterns of dead cells associated with exposure to UV radiation.
As with humans, the lighter-skinned whales seemed to have the most trouble dealing with the sun. Blue whales had more severe skin damage than darker-skinned mammals—like fin whales and sperm whales—even though the latter spend bigger chunks of time at the surface.
Fortunately, the study found no indications of skin cancer among the whales studied, although Martinez-Levasseur, who is also a Ph.D. student at Queen Mary, University of London, noted that only tiny samples were taken of the massive animals.
Showing posts with label ozone. Show all posts
Showing posts with label ozone. Show all posts
Tuesday, November 16, 2010
Friday, September 21, 2007
"The Chemical That Must Not Be Named"
by Stephen Leahy
Delegates from 191 nations are on the verge of an agreement under the Montreal Protocol for faster elimination of ozone-depleting chemicals, but the United States insists it must continue to use the banned pesticide methyl bromide....
MONTREAL - Even as another enormous ozone hole forms over the Antarctic this week, the rest of the world appears to be giving in to U.S. demands despite the fact that the use of methyl bromide in developed countries was supposed to have been completely phased out by Jan. 1, 2005 under the Montreal Protocol on Substances that Deplete the Ozone Layer.
‘It’s a black mark on this meeting. It is the chemical that must not be named,’ said David Doniger, climate policy director at the Natural Resources Defence Council, a U.S. environmental group.
‘There is a powerful lobby group of strawberry and vegetable growers in Washington,’ Doniger told IPS.
Methyl bromide is a highly toxic fumigant pesticide which is injected into soil to sterilise it before planting crops. It is also used as a post-harvest decontaminant of products and storage areas. Although it is highly effective in eradicating pests such as nematodes, weeds, insects and rodents, it depletes the ozone layer and poses a danger to human health.
While alternatives exist for more than 93 percent of the applications of methyl bromide, some countries such as the U.S., Japan and Israel claimed that because of regulatory restrictions, availability, cost and local conditions, they had little choice but to continue its use as a pest control. And so despite the ban, the Montreal Protocol allows ‘critical use exemptions’ for countries to continue to use banned substances for a short period of time until they can find a substitute.
In 2006, the United States received an exemption to use 8,000 tonnes of methyl bromide, compared to 5,000 tonnes for the rest of the developed world combined.
At the 19th Meeting of the Parties here in Montreal, the committee reporting on methyl bromide use reported ‘excellent progress’ in the continuing phase-out of the chemical and that not many applications for critical use exemptions had been received. The notable exception continues to be the U.S., which has applied for 6,500 tonnes for 2008 and 5,000 tonnes for 2009, even as the rest of the developed world has dropped significantly to just 1,900 and 1,400 tonnes, respectively.
The delegate from Switzerland expressed concern that some countries were asking for large amounts and that 40 percent of the stocks were not being used for critical uses. The United States maintains a large inventory of methyl bromide in excess of 8,000 tonnes, but the U.S. representative said these would be used up by 2009.
Emissions of methyl bromide have an immediate impact on the ozone layer, noted Janos Mate of Greenpeace International.
‘Scientists think it has three to 10 times the impact of other chemicals,’ Mate told IPS.
The ozone layer will be at its ‘most delicate’ over next few decades before it begins to significantly recover. Climate change is slowing this recovery, and the impacts are not fully understood, he said.
The ozone layer is the part of the atmosphere 25 kilometres up that acts as a shield protecting life on Earth from damaging ultraviolet rays, which can cause sunburns, skin cancer and cataracts. The rays can also harm marine life.
In the past two years, ozone holes larger than Europe have opened over the Antarctic and Southern Ocean. The World Metrological Organisation reported this week that the hole is back and bigger than ever. And it could grow larger as spring returns to the southern hemisphere.
Climate change appears to playing a role in the formation of these holes. Paradoxically, as the Earth warms at the surface, in the polar regions the upper atmosphere is getting colder, creating just the right conditions for chemicals like chlorine and bromine to destroy ozone...
Delegates from 191 nations are on the verge of an agreement under the Montreal Protocol for faster elimination of ozone-depleting chemicals, but the United States insists it must continue to use the banned pesticide methyl bromide....
MONTREAL - Even as another enormous ozone hole forms over the Antarctic this week, the rest of the world appears to be giving in to U.S. demands despite the fact that the use of methyl bromide in developed countries was supposed to have been completely phased out by Jan. 1, 2005 under the Montreal Protocol on Substances that Deplete the Ozone Layer.
‘It’s a black mark on this meeting. It is the chemical that must not be named,’ said David Doniger, climate policy director at the Natural Resources Defence Council, a U.S. environmental group.
‘There is a powerful lobby group of strawberry and vegetable growers in Washington,’ Doniger told IPS.
Methyl bromide is a highly toxic fumigant pesticide which is injected into soil to sterilise it before planting crops. It is also used as a post-harvest decontaminant of products and storage areas. Although it is highly effective in eradicating pests such as nematodes, weeds, insects and rodents, it depletes the ozone layer and poses a danger to human health.
While alternatives exist for more than 93 percent of the applications of methyl bromide, some countries such as the U.S., Japan and Israel claimed that because of regulatory restrictions, availability, cost and local conditions, they had little choice but to continue its use as a pest control. And so despite the ban, the Montreal Protocol allows ‘critical use exemptions’ for countries to continue to use banned substances for a short period of time until they can find a substitute.
In 2006, the United States received an exemption to use 8,000 tonnes of methyl bromide, compared to 5,000 tonnes for the rest of the developed world combined.
At the 19th Meeting of the Parties here in Montreal, the committee reporting on methyl bromide use reported ‘excellent progress’ in the continuing phase-out of the chemical and that not many applications for critical use exemptions had been received. The notable exception continues to be the U.S., which has applied for 6,500 tonnes for 2008 and 5,000 tonnes for 2009, even as the rest of the developed world has dropped significantly to just 1,900 and 1,400 tonnes, respectively.
The delegate from Switzerland expressed concern that some countries were asking for large amounts and that 40 percent of the stocks were not being used for critical uses. The United States maintains a large inventory of methyl bromide in excess of 8,000 tonnes, but the U.S. representative said these would be used up by 2009.
Emissions of methyl bromide have an immediate impact on the ozone layer, noted Janos Mate of Greenpeace International.
‘Scientists think it has three to 10 times the impact of other chemicals,’ Mate told IPS.
The ozone layer will be at its ‘most delicate’ over next few decades before it begins to significantly recover. Climate change is slowing this recovery, and the impacts are not fully understood, he said.
The ozone layer is the part of the atmosphere 25 kilometres up that acts as a shield protecting life on Earth from damaging ultraviolet rays, which can cause sunburns, skin cancer and cataracts. The rays can also harm marine life.
In the past two years, ozone holes larger than Europe have opened over the Antarctic and Southern Ocean. The World Metrological Organisation reported this week that the hole is back and bigger than ever. And it could grow larger as spring returns to the southern hemisphere.
Climate change appears to playing a role in the formation of these holes. Paradoxically, as the Earth warms at the surface, in the polar regions the upper atmosphere is getting colder, creating just the right conditions for chemicals like chlorine and bromine to destroy ozone...
Wednesday, July 25, 2007
"Ozone cuts plant growth, spurs global warming: study"
By Deborah Zabarenko, Environment Correspondent
WASHINGTON (Reuters) - The affects of greenhouse gas ozone, which has been increasing near Earth's surface since 1850, could seriously cut into crop yields and spur global warming this century, scientists reported on Wednesday.
Ozone in the troposphere -- the lowest level of the atmosphere -- damages plants and affects their ability to absorb carbon dioxide, another global warming gas whose release into the atmosphere accelerates climate change, the researchers wrote in the journal Nature.
While carbon dioxide is blamed for global warming, it also has a beneficial effect on plant growth, and ozone counteracts this effect, said Stephen Sitch, a climate researcher at Britain's Met Office, which deals with meteorology.
"As CO2 (carbon dioxide) increases in the atmosphere, that stimulates plant growth," Sitch said by telephone. He noted that many scientific simulations that predict the impact of global warming have included this effect but "they haven't included the other effect, the negative effect of ozone damaging productivity."
Plants and soil currently slow down global warming by storing about a quarter of human carbon dioxide emissions, but that could change if near-surface ozone increases, the researchers said.
Projections of this rise in ozone "could lead to significant reductions in regional plant production and crop yields," they said in a statement.
Carbon dioxide's fertilizing effect can be powerful, Sitch and his colleagues reported, pushing global plant productivity by 88.4 billion tons a year.
This figure does not take into account the depressing effect of ozone; with that factored in, the fertilizing power of carbon dioxide is 58.4 billion tons, the scientists wrote.
Without accounting for increased ozone, earlier simulations have underestimated the amount of carbon dioxide that will remain in the atmosphere, Sitch said.
Ozone's damaging effect on plants means they will suck up less carbon dioxide from the atmosphere, leaving more of this chemical to contribute to greenhouse warming, he said.
"Carbon dioxide is the largest greenhouse warming gas but ... (ozone) is reducing plant productivity by an appreciable amount," Sitch said.
Ozone has doubled since the mid-19th century due to chemical emissions from vehicles, industrial processes and the burning of forests, the British climate researchers wrote. Carbon dioxide has also risen over that period.
Unlike carbon dioxide, which is directly caused by these human-spawned emissions, ozone is a so-called secondary air pollutant, produced by reactions with other chemicals like nitrogen oxide and carbon monoxide.
Tropospheric ozone is different from stratospheric ozone, which contributes to a protective layer high above Earth's surface that guards against harmful solar radiation.
WASHINGTON (Reuters) - The affects of greenhouse gas ozone, which has been increasing near Earth's surface since 1850, could seriously cut into crop yields and spur global warming this century, scientists reported on Wednesday.
Ozone in the troposphere -- the lowest level of the atmosphere -- damages plants and affects their ability to absorb carbon dioxide, another global warming gas whose release into the atmosphere accelerates climate change, the researchers wrote in the journal Nature.
While carbon dioxide is blamed for global warming, it also has a beneficial effect on plant growth, and ozone counteracts this effect, said Stephen Sitch, a climate researcher at Britain's Met Office, which deals with meteorology.
"As CO2 (carbon dioxide) increases in the atmosphere, that stimulates plant growth," Sitch said by telephone. He noted that many scientific simulations that predict the impact of global warming have included this effect but "they haven't included the other effect, the negative effect of ozone damaging productivity."
Plants and soil currently slow down global warming by storing about a quarter of human carbon dioxide emissions, but that could change if near-surface ozone increases, the researchers said.
Projections of this rise in ozone "could lead to significant reductions in regional plant production and crop yields," they said in a statement.
Carbon dioxide's fertilizing effect can be powerful, Sitch and his colleagues reported, pushing global plant productivity by 88.4 billion tons a year.
This figure does not take into account the depressing effect of ozone; with that factored in, the fertilizing power of carbon dioxide is 58.4 billion tons, the scientists wrote.
Without accounting for increased ozone, earlier simulations have underestimated the amount of carbon dioxide that will remain in the atmosphere, Sitch said.
Ozone's damaging effect on plants means they will suck up less carbon dioxide from the atmosphere, leaving more of this chemical to contribute to greenhouse warming, he said.
"Carbon dioxide is the largest greenhouse warming gas but ... (ozone) is reducing plant productivity by an appreciable amount," Sitch said.
Ozone has doubled since the mid-19th century due to chemical emissions from vehicles, industrial processes and the burning of forests, the British climate researchers wrote. Carbon dioxide has also risen over that period.
Unlike carbon dioxide, which is directly caused by these human-spawned emissions, ozone is a so-called secondary air pollutant, produced by reactions with other chemicals like nitrogen oxide and carbon monoxide.
Tropospheric ozone is different from stratospheric ozone, which contributes to a protective layer high above Earth's surface that guards against harmful solar radiation.
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