Not only is Earth's surface warming, but the troposphere -- the lowest level of the atmosphere, where weather occurs -- is heating up too, U.S. and British meteorologists reported on Monday.
In a review of four decades of data on troposphere temperatures, the scientists found that warming in this key atmospheric layer was occurring, just as many researchers expected it would as more greenhouse gases built up and trapped heat close to the Earth.
This study aims to put to rest a controversy that began 20 years ago, when a 1990 scientific report based on satellite observations raised questions about whether the troposphere was warming, even as Earth's surface temperatures climbed.
The original discrepancy between what the climate models predicted and what satellites and weather balloons measured had to do with how the observations were made, according to Dian Seidel, research meteorologist for the U.S. National Oceanic and Atmospheric Administration.
It was relatively easy to track surface temperatures, since most weather stations sat on or close to the ground, Seidel said by telephone from NOAA's Air Resources Laboratory in Silver Spring, Maryland, outside Washington.
Measuring temperature in the troposphere is more complicated. Starting in the late 1950s, scientists dangled weather instruments from big balloons, with the data sent back to researchers by radio transmission as the balloons rose through the six miles of the troposphere.
Showing posts with label Chelsea Sheppard. Show all posts
Showing posts with label Chelsea Sheppard. Show all posts
Wednesday, May 4, 2011
Spiders may be able to adapt to climate change
The Yale research examined a well-studied grassland food web, made up of a predatory spider, its grasshopper prey, and the plants grasshoppers fed on. The spider's predatory behaviour is known to be temperature-sensitive, decreasing with increased temperatures. Researchers had expected higher temperatures to stop the spiders preying on grasshoppers, leading to more plants being eaten.
However, in the study, spider populations from warmer areas tolerated higher temperature ranges better than the populations from cooler areas and continued to control the grasshopper popualtion. This suggests they can adapt to local conditions and maintain their vital role in the community despite increased temperatures.
'Species are almost certainly adapting to the climate change Earth has experienced during the past century,' study author Dr Brandon Barton told the Ecologist. 'My results show that species have the capacity to adapt to a range of temperatures, similar to those predicted by climate change models, and that a species' role in the community can be conserved by this adaptation.'
Many similar experiments expose organisms to short-term, sudden increases in temperature, which does not allow for long-term gradual processes like climate change. Barton's work overcomes these limitations by looking at populations along a natural temperature gradient to see if long-term changes in temperature would affect small-scale food webs. He sampled spiders at sites from a 500km, north-south axis, along the east coast of the United States, where temperature varied by 4.8C.
However, in the study, spider populations from warmer areas tolerated higher temperature ranges better than the populations from cooler areas and continued to control the grasshopper popualtion. This suggests they can adapt to local conditions and maintain their vital role in the community despite increased temperatures.
'Species are almost certainly adapting to the climate change Earth has experienced during the past century,' study author Dr Brandon Barton told the Ecologist. 'My results show that species have the capacity to adapt to a range of temperatures, similar to those predicted by climate change models, and that a species' role in the community can be conserved by this adaptation.'
Many similar experiments expose organisms to short-term, sudden increases in temperature, which does not allow for long-term gradual processes like climate change. Barton's work overcomes these limitations by looking at populations along a natural temperature gradient to see if long-term changes in temperature would affect small-scale food webs. He sampled spiders at sites from a 500km, north-south axis, along the east coast of the United States, where temperature varied by 4.8C.
Windier World
The world is getting breezier, according to a new study, which found a slow but steady increase in top wind speeds across the oceans over the last 23 years.
Although global warming is a suspect, researchers can't say for sure whether climate change is behind the growing gusts. The trend could simply be part of a natural and long-term cycle that pushes wind speeds both up and down over the course of many decades.
But if winds continue to pick up at the same rate, hurricanes could become far more damaging by the middle of the century. Among other implications, engineers would need to rethink they way they plan coastal and offshore structures.
"We may be observing an upward increase of something that, in the future, will go down again," said Ian Young, a physical oceanographer at the Australian National University in Canberra. "However, the fact that we're seeing this on a global basis in both the northern and the southern hemispheres suggests it may be a long-term trend rather than an oscillation. If we're going to design things in the future, we may want to actually factor in oceanic waves going up."
Winds over the oceans directly influence wave heights, and orbiting satellites use altimeters to regularly monitor both. Scientists are interested in these measurements because they affect the exchange of heat and gasses between water and sky. Winds also influence the frequency and strength of major storms.
Although global warming is a suspect, researchers can't say for sure whether climate change is behind the growing gusts. The trend could simply be part of a natural and long-term cycle that pushes wind speeds both up and down over the course of many decades.
But if winds continue to pick up at the same rate, hurricanes could become far more damaging by the middle of the century. Among other implications, engineers would need to rethink they way they plan coastal and offshore structures.
"We may be observing an upward increase of something that, in the future, will go down again," said Ian Young, a physical oceanographer at the Australian National University in Canberra. "However, the fact that we're seeing this on a global basis in both the northern and the southern hemispheres suggests it may be a long-term trend rather than an oscillation. If we're going to design things in the future, we may want to actually factor in oceanic waves going up."
Winds over the oceans directly influence wave heights, and orbiting satellites use altimeters to regularly monitor both. Scientists are interested in these measurements because they affect the exchange of heat and gasses between water and sky. Winds also influence the frequency and strength of major storms.
Rising sea levels in China = problem.
Gradually rising sea levels caused by global warming over the past 30 years have contributed to a growing number of disasters along China's coast, state news agency Xinhua said on Wednesday.
Sea levels along China's coastline had risen 2.6 mm per year over the past three decades, Xinhua said, citing documents from the State Oceanic Administration.
Average air and sea temperatures in coastal areas had risen about 0.4 and 0.2 degrees Celsius respectively over the past 10 years, the news agency added.
"As a 'gradual' marine disaster, the cumulative effect of rising sea levels could 'aggravate storm tides, coastal erosion, seawater invasion and other disasters'," Xinhua cited the oceanic administration as saying.
An expert at the administration, Liu Kexiu, said the rising sea levels were a result of global warming.
"Other key factors are land subsidence caused by human activities, including over-exploitation of groundwater and massive construction of high buildings in coastal areas," Liu said.
China's high and rapidly climbing output of carbon dioxide, the main greenhouse gas pollutant from burning coal, oil and gas, has put it at the center of negotiations for a new world pact to reduce the emissions responsible for global warming.
The government has vowed to cut the amount of carbon dioxide emitted from fossil fuels per unit of gross domestic product growth by 17 percent in the next five years.
But China has repeatedly said it will not accept a more stringent, absolute cap on total emissions, calling it an unfair burden on developing nations that have much lower emissions per person than rich economies. It has also refused to say when its emissions could peak and begin to fall.
Sea levels along China's coastline had risen 2.6 mm per year over the past three decades, Xinhua said, citing documents from the State Oceanic Administration.
Average air and sea temperatures in coastal areas had risen about 0.4 and 0.2 degrees Celsius respectively over the past 10 years, the news agency added.
"As a 'gradual' marine disaster, the cumulative effect of rising sea levels could 'aggravate storm tides, coastal erosion, seawater invasion and other disasters'," Xinhua cited the oceanic administration as saying.
An expert at the administration, Liu Kexiu, said the rising sea levels were a result of global warming.
"Other key factors are land subsidence caused by human activities, including over-exploitation of groundwater and massive construction of high buildings in coastal areas," Liu said.
China's high and rapidly climbing output of carbon dioxide, the main greenhouse gas pollutant from burning coal, oil and gas, has put it at the center of negotiations for a new world pact to reduce the emissions responsible for global warming.
The government has vowed to cut the amount of carbon dioxide emitted from fossil fuels per unit of gross domestic product growth by 17 percent in the next five years.
But China has repeatedly said it will not accept a more stringent, absolute cap on total emissions, calling it an unfair burden on developing nations that have much lower emissions per person than rich economies. It has also refused to say when its emissions could peak and begin to fall.
Contraception could slow global warming? NO WAY!
Washington, D.C.-A new report from the Worldwatch Institute argues that assuring all women have access to contraception and taking steps to improve women's lives should be among key strategies in the fight against global climate change.
The report examines United Nations projections for population growth out to 2050, citing evidence that slower population growth through better family planning would mean huge reductions in carbon dioxide emissions. If the world's population leveled off at 8 billion by 2050 instead of reaching the more often projected 9 billion, for example, this would reduce CO2 emissions by more than if global deforestation were completely eliminated.
"Despite its key contribution to climate change, population and the role of women are largely ignored in the political and public debates on how to address the challenge," said report author Robert Engelman, Worldwatch's Vice President for Programs. "Population is associated with sensitive issues like sexuality, contraception, abortion, migration, and religion. But increasing women's reproductive rights should be at the heart of the climate discussion, in the same basket as strategies like increasing energy efficiency and researching new technologies."
The report draws on new studies that document the environmental pressures from soaring population growth. It also reports on the unique role that women can play in alleviating those pressures, even as women are disproportionally affected by the adverse effects of climate change. Finally, the report argues that humanity ultimately will need to slow population growth to tackle rising global temperatures, and that the only way to do this is by improving the well-being of women worldwide.
The report examines United Nations projections for population growth out to 2050, citing evidence that slower population growth through better family planning would mean huge reductions in carbon dioxide emissions. If the world's population leveled off at 8 billion by 2050 instead of reaching the more often projected 9 billion, for example, this would reduce CO2 emissions by more than if global deforestation were completely eliminated.
"Despite its key contribution to climate change, population and the role of women are largely ignored in the political and public debates on how to address the challenge," said report author Robert Engelman, Worldwatch's Vice President for Programs. "Population is associated with sensitive issues like sexuality, contraception, abortion, migration, and religion. But increasing women's reproductive rights should be at the heart of the climate discussion, in the same basket as strategies like increasing energy efficiency and researching new technologies."
The report draws on new studies that document the environmental pressures from soaring population growth. It also reports on the unique role that women can play in alleviating those pressures, even as women are disproportionally affected by the adverse effects of climate change. Finally, the report argues that humanity ultimately will need to slow population growth to tackle rising global temperatures, and that the only way to do this is by improving the well-being of women worldwide.
Coffee production and climate change
As if there were a need for even more evidence that global warming is a real, verifiable and evidenced threat, new research is showing Central and South American coffee production is drastically dropping because of higher global temperatures.
Add extreme rainfall totals to the mix and the result is rampant insects and damaged plants. If economics won't convince people the earth is warming, perhaps interrupting their coffee supply will.
A traditionally reliable and adequate income, coffee farming is becoming a more challenging option. Where entire communities once depended on coffee to perpetuate their economies, farming families need to find alternative sources of income.
Last year, production dropped 70%. A fungus called Coffee Rust is killing of coffee plants quickly where lower temperatures once prevented the spread of the fungus. If ever there was a clear connection between global warming and the declining of production and community stability.
Beans from the area that is seeing the most dramatic trouble produce 16% of Columbian coffee, and command high prices in specialty coffees. Don't think that insulates you generic brand coffee drinkers. The entire supply chain is cross-polinated (no pun intended) and will result in higher prices across the spectrum of quality.
Add extreme rainfall totals to the mix and the result is rampant insects and damaged plants. If economics won't convince people the earth is warming, perhaps interrupting their coffee supply will.
A traditionally reliable and adequate income, coffee farming is becoming a more challenging option. Where entire communities once depended on coffee to perpetuate their economies, farming families need to find alternative sources of income.
Last year, production dropped 70%. A fungus called Coffee Rust is killing of coffee plants quickly where lower temperatures once prevented the spread of the fungus. If ever there was a clear connection between global warming and the declining of production and community stability.
Beans from the area that is seeing the most dramatic trouble produce 16% of Columbian coffee, and command high prices in specialty coffees. Don't think that insulates you generic brand coffee drinkers. The entire supply chain is cross-polinated (no pun intended) and will result in higher prices across the spectrum of quality.
Brazil beats U.S. in climate change awareness
[RIO DE JANEIRO] Almost 80 per cent of Brazilians think global warming is caused by human activities, a survey has found, compared with less than half of Americans and around 70 per cent of Britons according to similar recent surveys.
Around 90 per cent of Brazilians believe that global warming is happening and think it is a serious issue, putting them on a par with Europeans and well ahead of Americans.
The results challenge the belief that in the developing world there is a lack of knowledge of the importance of climate change, said Yurij Castelfranchi, an expert on public perception of science based at the Federal University of Minas Gerais.
"The results show that climate change is on the agenda not only for the government but also for civil society," he told SciDev.Net.
More than 2,000 Brazilians were interviewed for the survey, which was conducted by the National Confederation of Industries (CNI) and published last month (December).
Around 90 per cent of Brazilians believe that global warming is happening and think it is a serious issue, putting them on a par with Europeans and well ahead of Americans.
The results challenge the belief that in the developing world there is a lack of knowledge of the importance of climate change, said Yurij Castelfranchi, an expert on public perception of science based at the Federal University of Minas Gerais.
"The results show that climate change is on the agenda not only for the government but also for civil society," he told SciDev.Net.
More than 2,000 Brazilians were interviewed for the survey, which was conducted by the National Confederation of Industries (CNI) and published last month (December).
Wednesday, March 2, 2011
Nuclear War, the answer to global warming?
How much colder would the world get?
A regional nuclear war would immediately cause average global temperatures to drop by 2.25 degrees Fahrenheit for the next two to three years. The most extremely affected areas — the tropics, Europe, Asia, and Alaska — would cool by up to 7.2 degrees, according to computer models. Even a decade after detonation, average world temperatures would remain nearly a full degree lower.
Why would temperatures plunge so far?
The explosions would send dust, soot, and ash into the sky, blotting out the sun for weeks. Smoke from the resulting fires would carry five million metric tons of black carbon into the Earth's atmosphere, where it would absorb the sun's heat.
How big of a nuclear war would it take to cool the planet?
Not that extensive, relatively speaking. These researchers used computer models assuming a war involving 50 to 100 bombs as big as the one the U.S. dropped on Hiroshima in World War II. That translates into just 0.03 percent of the world's current nuclear firepower. TIME ominously pointed out that could last several years. But the devastating effects of the plunge in temperatures, not to mention the other consequences of nuclear bombs, would hurt the world for generations. Here, a quick guide: that India and Pakistan already have enough bombs in their arsenals to do the trick.
Friday, February 25, 2011
"Geongineering"
Blasting tons of sulfate particles into the sky to reflect sunlight away from Earth; filling the ocean with iron filings to grow plankton that will suck up carbon; even dimming sunlight with space shades. ?!?!
Scientists call it "geoengineering," but in plain speak, it means things like this: blasting tons of sulfate particles into the sky to reflect sunlight away from Earth; filling the ocean with iron filings to grow plankton that will suck up carbon; even dimming sunlight with space shades.
Scientists call it "geoengineering," but in plain speak, it means things like this: blasting tons of sulfate particles into the sky to reflect sunlight away from Earth; filling the ocean with iron filings to grow plankton that will suck up carbon; even dimming sunlight with space shades.
Each brings its own set of risks, but in a world fretting about the consequences of global warming, are these ideas whose time has come?
With 2010 tying as the world's warmest year on record and efforts to slow greenhouse gas emissions looking stymied, calls are rising for research into engineering our way out of global warming — everything from launching solar shade spacecraft to genetically engineering green deserts. An international consortium of 12 universities and research institutes on Tuesday, for example, announced plans to pioneer large-scale "ocean fertilization" experiments aimed at using the sea to pull more greenhouse gases out of the sky.
BLACK CARBON!
Unexpected threats to the health of global systems keep emerging. Twenty years ago we didn't recognize global warming. Ten years ago we didn't know about ocean acidification. This might be the landmark week in which a broad public recognized a new threat to the global climate -- black carbon.
The United Nations Environment Programme (UNEP) has just published a science-based analysis of the climate forcing effects of black carbon. The findings are that cutting black carbon and troposperhic ozone now could halve regional warming for 30 to 60 years and reduce global warming by half a degree. It turns out that reducing black carbon emissions needs to become a priority. According to the United Nations Economic Commission for Europe (UNECE), greenhouse gas reductions alone will not avert further destruction of the arctic; black carbon and ozone reductions are needed.
Black carbon is made up of fine particles. It is colloquially known as soot. It comes from diesel engines as well as burning wood, waste and gas. The health effects of black carbon are well known. In London, for example, the soot from our beloved taxis and other sources leads to the early death of 4,500 people a year according to the government.
The United Nations Environment Programme (UNEP) has just published a science-based analysis of the climate forcing effects of black carbon. The findings are that cutting black carbon and troposperhic ozone now could halve regional warming for 30 to 60 years and reduce global warming by half a degree. It turns out that reducing black carbon emissions needs to become a priority. According to the United Nations Economic Commission for Europe (UNECE), greenhouse gas reductions alone will not avert further destruction of the arctic; black carbon and ozone reductions are needed.
Black carbon is made up of fine particles. It is colloquially known as soot. It comes from diesel engines as well as burning wood, waste and gas. The health effects of black carbon are well known. In London, for example, the soot from our beloved taxis and other sources leads to the early death of 4,500 people a year according to the government.
Thursday, February 10, 2011
Senate Climate Bill Would Cut Emissions 20% by 2020.
The bill, introduced by Sen. Barbara Boxer of California, chair of the Senate Environment and Public Works Committee, and Sen. John Kerry of Massachusetts, calls for the U.S. to reduce its emissions by 20 percent below 2005 levels by 2020, and 83 percent below 2005 levels by 2050.
That's a slightly steeper short-term cut than the one passed in a controversial House bill in June, which called for 17 percent reduction by 2020. The bills require equal levels of cuts by 2050.
Both bills would establish a cap-and-trade system that would limit greenhouse gas emissions by issuing pollution offsets. Power plants, factories and others could buy and sell those offsets in a regulated market. The number would be reduced over time, reducing the total amount of greenhouse gas emissions.
"We know clean energy is the ticket to strong, sustainable economic growth," Boxer said at a rally to introduce the bill.
Most environmental lobbyists said they were pleased with the legislation.
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