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.
Wednesday, May 4, 2011
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).
Tuesday, May 3, 2011
FLOATING INTO THE FUTURE!!!!!!!
The notion that airships represent the future of air cargo is being revived by a new generation of entrepreneurs some 75 years after a catastrophic fireball brought the industry to a screeching halt.Far safer than the Hindenburg, whose tragic 1937 docking remains an icon of aerospace gone wrong, these modern airships are a hybrid of lighter-than-air and fixed-wing aircraft. They can loft enormous payloads without requiring the acres of tarmac or miles of roadway necessary for conventional air and truck transport. And they do so at a fraction of the fuel and cost of aircraft.
Airships "give you access and much larger payloads at much lower costs," said Peter DeRobertis, project leader for commercial hybrid air vehicles at Lockheed Martin's Aeronautics and Skunk Works division in Fort Worth, Texas. "It's also a green aircraft; you're not polluting."
Today's airships could conceivably be used to transport everything from ripe pineapples to heavy industrial equipment direct to the customer. Shippers, for example, could roll tractors, backhoes, and road graders onto a 50-ton hybrid vehicle at a factory and roll them off at the job site, easing logistics and cost.
A handful of companies have prototypes under development. Lockheed has an airship in the works dubbed SkyTug that should be commercially available by late 2013 with a range of 1,000 nautical miles and a 20-ton payload. The 50-ton Skyfreighter is expected to follow in late 2014.
The industry's future is initially aimed at leapfrogging the conventional cargo transport infrastructure, freighting goods where highways and airports don't exist - Canada's frozen north; China's western frontier; remote parts of Africa, Asia, and South America. No airships are commercially available for cargo transport there yet. But once established on the frontiers, experts say their versatility, cost and fuel advantages should allow airships to penetrate mature freight markets like the United States.
'Hard to justify any roads'
Optimistic entrepreneurs have made similar predictions before, however. Germany-based Cargolifter AG burned through some $500 million without building so much as a prototype before it went belly-up in 2002.
But today's technology is much improved from earlier, flawed approaches. And the potential market is vast.
In northern Canada, for instance, some 4 million square miles of real estate lie north of rail lines and all-weather highways, and warming winters are making seasonally-constructed ice roads less reliable. Historically, ice roads were open three months during the winter. Today, they barely see 30 days of operation per season.
link HERE:
http://wwwp.dailyclimate.org/tdc-newsroom/2011/05/airships-as-climate-solution
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