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Friday, August 31, 2012
Thursday, August 30, 2012
Public release date: 30-Aug-2012
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Contact: Michael Bishop
michael.bishop@iop.org
01-179-301-032
Institute of Physics
[ Print | E-mail |
Share ] [ Close Window ] Contact: Michael Bishop
michael.bishop@iop.org
01-179-301-032
Institute of Physics
Delivering solar geoengineering materials may be feasible and affordable
A cost analysis of the technologies needed to transport materials into the stratosphere to reduce the amount of sunlight hitting Earth and therefore reduce the effects of global climate change has shown that they are both feasible and affordable.
Published today, 31 August 2012, in IOP Publishing's journal Environmental Research Letters, the study has shown that the basic technology currently exists and could be assembled and implemented in a number of different forms for less than USD $5 billion a year.
Put into context, the cost of reducing carbon dioxide emissions is currently estimated to be between 0.2 and 2.5 per cent of GDP in the year 2030, which is equivalent to roughly USD $200 to $2000 billion.
Solar radiation management (SRM) looks to induce the effects similar to those observed after volcanic eruptions; however, the authors state that it is not a preferred strategy and that such a claim could only be made after the thorough investigation of the implications, risks and costs associated with these issues.
The authors caution that reducing incident sunlight does nothing at all to reduce greenhouse gas concentrations in the atmosphere, nor the resulting increase in the acid content of the oceans.
They note that other research has shown that the effects of solar radiation management are not uniform, and would cause different temperature and precipitation changes in different countries.
Co-author of the study, Professor Jay Apt, said: "As economists are beginning to explore the role of several types of geoengineering, it is important that a cost analysis of SRM is carried out. The basic feasibility of SRM with current technology is still being disputed and some political scientists and policy makers are concerned about unilateral action."
In the study, the researchers, from Aurora Flight Sciences, Harvard University and Carnegie Mellon University, performed an engineering cost analysis on six systems capable of delivering 1 million metric tonnes of material to altitudes of 18 km: existing aircraft, a new airplane designed to perform at altitudes up to 30 km, a new hybrid airship, rockets, guns and suspended pipes carrying gas or slurry to inject the particles into the atmosphere.
Based on existing research into solar radiation management, the researchers performed their cost analyses for systems that could deliver around one million tonnes of aerosols each year at an altitude between 18 and 25 km and between a latitude range of 30°N and 30°S.
The study concluded that using aircraft is easily within the current capabilities of aerospace engineering, manufacturing and operations. The development of new, specialized aircraft appeared to be the cheapest option, with costs of around $1 to $2 billion a year; existing aircraft would be more expensive as they are not optimised for high altitudes and would need considerable and expensive modifications to do so.
Guns and rockets appeared to be capable of delivering materials at high altitudes but the costs associated with these are much higher than those of airplanes and airships due to their lack of reusability.
Although completely theoretical at this point in time, a large gas pipe, rising to 20 km in the sky and suspended by helium-filled floating platforms, would offer the lowest recurring cost-per-kilogram of particles delivered but the costs of research into the materials required, the development of the pipe and the testing to ensure safety, would be high; the whole system carries a large uncertainty.
Professor Apt continued: "We hope our study will help other scientists looking at more novel methods for dispersing particles and help them to explore methods with increased efficiency and reduced environmental risk."
The researchers make it clear that they have not sought to address the science of aerosols in the stratosphere, nor issues of risk, effectiveness or governance that will add to the costs of solar radiation management geoengineering.
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Notes to Editors
Contact
1. For further information, a full draft of the journal paper or contact with one of the researchers, contact IOP Press Officer, Michael Bishop: Tel: 0117 930 1032 E-mail: Michael.bishop@iop.org
Cost analysis of stratospheric albedo modification delivery systems
2. The published version of the paper 'Cost analysis of stratospheric albedo modification delivery systems' (Justin McClellan, David W Keith and Jay Apt 2012 Environ. Res. Lett. 7 034019
Environmental Research Letters
Sunday, August 19, 2012
Tuesday, August 14, 2012
Thursday, August 9, 2012
Monday, August 6, 2012
Saturday, August 4, 2012
Is current geoengineering responsible for our drought ?
Climate fixes 'pose drought risk' | ||
  Attempts to control the climate might change precipitation, say researchers The use of geo-engineering to slow global warming may increase the risk of drought, according to a paper in Science journal. Methods put forward include reflecting solar radiation back into space using giant mirrors or aerosol particles. But the authors warn that such attempts to control the climate could also cause major changes in precipitation. They want the effect on rainfall to be assessed before any action is taken. Gabriele Hegerl of the Grant Institute at University of Edinburgh and Susan Solomon of National Oceanic and Atmospheric Administration (NOAA) at Boulder, Colorado, write that "if geo-engineering studies focus too heavily on warming, critical risks associated with such possible "cures" will not be evaluated appropriately". They argue that climate change is about much more than changes in temperature. So using temperature alone to monitor the effects of geo-engineering could be dangerous. Underestimating effects They cite the powerful effects on rainfall of volcanic eruptions which also prevent solar radiation reaching the Earth's surface, albeit by throwing up dust rather than reflecting the radiation back into space. For example in 1991, the eruption of Mount Pinatubo not only reduced global temperatures but also led to increases in drought. The pair correlated 20th Century weather records with data for the increase in greenhouse gases and dates for major volcanic eruptions.
This revealed that greenhouse emissions tend to slightly increase rainfall in the short term but also showed that reduction in rainfall in the months following a major volcanic eruption is far more dramatic. The authors note that current climate models tend to underestimate the effects on precipitation of both greenhouse gases and of volcanic eruptions. The article warns that geo-engineering of this type, combined with the effects of global warming could produce reductions in regional rainfall that could rival those of past major droughts, leading to winners and losers among the human population and possible conflicts over water. They conclude: "optimism about a geo-engineered 'easy way out' should be tempered by examination of currently observed climate changes." | ||
Tuesday, July 17, 2012
Geoengineering projects around the world - map
ETC Group has produced a world map of geoengineering that represents the first attempt to document the expanding scope of research and experimentation in the large-scale manipulation of Earth or climate systems
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Trial Balloon: A Tiny Geoengineering Experiment
By HENRY FOUNTAIN
Two Harvard professors said Tuesday they were developing a proposal for what would be a first-of-its-kind field experiment to test the risks and effectiveness of a geoengineering technology for intervening in the earth’s climate.
The experiment, which would be conducted from a balloon launched from a NASA facility in New Mexico, would involve putting “micro” amounts of sulfate particles into the air with the goal of learning how they combine with water vapor and affect atmospheric ozone.
The researchers, James G. Anderson, a professor of atmospheric chemistry, and David W. Keith, whose field is applied physics, said the amounts involved would be so small that they would have no effect on climate — locally, regionally or globally. “This is an experiment that is completely nonintrusive,” Dr. Anderson said.
(His remarks contradicted a report in The Guardian that the experiment would involve spraying tens or hundreds of pounds of “sun-reflecting chemical particles into the atmosphere to artificially cool the planet.”)
Geoengineering is a catch-all term for technologies that have been proposed for combating climate change. The technologies fall into two categories: those that would remove some of the heat-trapping carbon dioxide already in the atmosphere, and others that would reduce the amount of sunlight warming the planet.
Geoengineering is a catch-all term for technologies that have been proposed for combating climate change. The technologies fall into two categories: those that would remove some of the heat-trapping carbon dioxide already in the atmosphere, and others that would reduce the amount of sunlight warming the planet.
The Harvard researchers’ proposal would focus on an often-suggested means of reducing sunlight: injecting sulfate particles into the atmosphere, where they would combine with water vapor to form aerosols that would reflect some of the sun’s rays. The process would mimic what happens naturally from the eruption of large volcanoes like Mount Pinatubo in the Philippines, which in 1991 spewed millions of tons of sulfur, cooling surface temperatures by about 1 degree Fahrenheit for several years.
But sulfate particles also affect chlorine in the atmosphere, converting it to a form that destroys ozone, a gas that shields the earth from some harmful solar radiation. So before anyone can seriously suggest injecting sulfates into the atmosphere, the effect on ozone must be studied, the researchers said.
Dr. Anderson bristled at the suggestion in The Guardian report that the experiment would use large amounts of the particles. “The whole point of this is to avoid using any quantities of anything that could possibly damage the ozone layer,” he said.
He and Dr. Keith said they expected to have a full proposal written by the end of the year and then would seek public money to pay for it. If they receive funding, the experiment could take place next year, Dr. Anderson said.
Dr. Keith, who is studying other geoengineering technologies including those that would remove carbon dioxide directly from the air, is among several scientists who have received more than $4 million for such research from Bill Gates, a co-founder of Microsoft. But Dr. Keith said he felt strongly that any experiment outside a laboratory that involved injecting even tiny amounts of particles into the atmosphere should involve “public funding and public governance.”
“We will not do an outdoor experiment with that funding,” he said, referring to the money from Mr. Gates.
Geoengineering as an approach to fighting climate change has its share of critics, who argue that the technologies would be costly to develop on a global scale, are generally unproven, and could have disastrous unintended consequences. Even entertaining the idea of geoengineering, some critics say, only serves to distract society from what should be its primary goal: reducing carbon dioxide emissions.
But even some who doubt that geoengineering is a good idea have said that some research in the field should proceed. There has been almost no field research on technologies to reflect sunlight; a British experiment testing the feasibility of pumping liquids to great heights was canceled this year after a dispute over patents.
“I do think that experiments in the outdoors make sense,” Dr. Keith said. “But they need to address clear scientific questions.”
Monday, July 16, 2012
Iran drought part of 'soft war' by West: VP
AFP – 6 hours agoRELATED CONTENT
- A dried-up water canal in Eghlid highlights drought in the southern Iranian province …
The drought in southern Iran is part of a "soft war" launched against the Islamic republic by the West, the Fars news agency quoted an Iranian vice president as saying on Monday.
"I am suspicious about the drought in the southern part of the country," Hassan Mousavi, who also heads Iran's cultural heritage and tourism organisation, said at a ceremony to introdue the nation's new chief of meteorological department.
"The world arrogance and colonist (term used by Iranian authorities to label the West) are influencing Iran's climate conditions using technology... The drought is an acute issue and soft war is completely evident... This level of drought is not normal."
Iran has experienced several droughts in recent years, especially in the south where it was hit in recent weeks by violent sand storms that engulfed several cities.
Sand storms particularly enter Iran from neighbouring Iraq where desertification has increased over the last two decades due to wars.
Last year, Iranian President Mahmoud Ahmadinejad accused Western countries of devising plans to "cause drought" in Iran, adding that "European countries are using special equipment to force clouds to dump" their water on their continent.
Iranian leaders claim on a daily basis that Western countries, led by arch-foe the United States, devise "plots" in many forms to undermine the Islamic republic and to impede its economic and scientific development.
They also accuse world powers of colluding against Iran's national unity, independence, political establishment, culture as well as international relations.
Sunday, June 24, 2012
Tuesday, June 19, 2012
MORE PROPAGANDA FROM THE UK
The transatlantic jet trails visible from space: How 'contrails' can stay in the sky for up to 14 hours
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Like a giant game of crosses without the naughts, these incredible jet engine trails can be seen criss-crossing the Atlantic from space.
NASA's Terra satellite captured these two amazing images of aircraft trails, or 'contrails' as they are known, spreading across the sky off the coast of Newfoundland, Canada.
The spectacular effect forms in the wake of passing aircraft due to the extra particles and water vapor contained in their exhaust.
NASA said these it has observed these clusters of contrails lasting as long as 14 hours, though most get a shorter lifespan of four to six hours.
Jet trails: NASA's satellite captured the jet trails, pictured, criss-crossing the Atlantic on May 26
These photographs, taken over two hours on May 26, capture contrails that were likely caused by commercial aircraft flying west to North America from the UK and Europe.
The contrails are arrayed in X-shaped patterns and a cirrus cloud is visible to the left of both images.
The airplane signatures with distinct edges are visible in the first, older image, but two hours later have grown wispier and spread outward as winds have blown them south and east.
The temperature and humidity of the air affects how long contrails last - when the air is dry, they remain visible for mere seconds or minutes.
But when the air is humid, as was the case here, contrails can be long-lived and spread outward until they become difficult to distinguish from naturally-occurring cirrus clouds.
Faded: A second image, pictured, captured two hours later shows the jet trails spreading and growing wispier
Climate scientists are fascinated by long-lived, spreading contrails because they reflect sunlight and trap infrared radiation.
A contrail in an otherwise clear sky reduces the amount of solar radiation that reaches Earth’s surface, while increasing the amount of infrared radiation absorbed by the atmosphere.
These opposing effects make it difficult for scientists to pin down the exact effect contrails have on climate.
'Overall, contrails create additional cirrus cloud cover,' said Patrick Minnis, a senior scientist at NASA's Langley Research Center.
'Current estimates indicate that contrails have a small warming effect, but the extent of the additional coverage and the amount of warming remain quite uncertain.'
In 2004, Mr Minnis published a study of surface observations that found cirrus cloud cover had increased by 3 per cent between 1971 and 1995 over the United States, the most recent data available.
The two new pictures were taken by the Terra satellite's Moderate Resolution Imaging Spectroradiometer, used for photographing clouds and atmospheric features.
Read more: http://www.dailymail.co.uk/sciencetech/article-2160873/NASA-satellite-images-capture-commercial-jet-engine-trails-space.html#ixzz1yOdd1HQz
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