Jeff Bezos's rag has a story about "geoengineering": Alan, were you quoted correctly here? Did you really say "No technology exists to do solar radiation management"? If so, how do you square this position with the results of the Aurora report ( http://www.keith.seas.harvard.edu/Misc/AuroraGeoReport.pdf)
Justin McClellan, David W Keith, Jay Apt. (2012). Cost analysis of stratospheric albedo modification delivery systems. *Environmental Research Letters*, doi:10.1088/1748-9326/7/3/034019. (PDF<http://www.keith.seas.harvard.edu/papers/159.McClellan.2012.CostAnalysisOfStratosp.e.pdf> ) http://iopscience.iop.org/1748-9326/7/3/034019 Note that the abstract of this paper states "We evaluate existing aircraft cost of acquisition and operations, ... " This does not sound like "No technology exists ..." http://www.washingtonpost.com/national/health-science/scientists-studying-solar-radiation-management-as-a-way-to-cool-planet/2013/09/08/cfb9def8-170c-11e3-be6e-dc6ae8a5b3a8_story.html Scientists studying solar radiation management as a way to cool planet Arlan N.Aeg/AFP/Getty Images - This picture, taken June 12, 1991, shows a giant mushroom cloud of steam and ash exploding out of the Mount Pinatubo volcano during its eruption as seen from inside a former U.S. air base in the Philippines. By Lenny Bernstein<http://www.washingtonpost.com/lenny-bernstein/2011/02/24/ABHUJyI_page.html> , Updated: Sunday, September 8, 7:25 PM E-mail the writer<[email protected]?subject=Reader%20feedback%20for%20'Scientists%20studying%20solar%20radiation%20management%20as%20a%20way%20to%20cool%20planet'> The 1991 eruption of Mount Pinatubo <http://pubs.usgs.gov/fs/1997/fs113-97/>, a volcano in the Philippines, blasted enough fine particles and sulfur dioxide gas into the atmosphere to envelop the Earth in a high-altitude cloud for the better part of two months. When scientists checked in 1992, they determined that the cloud had deflected enough sunlight to cool the planet by about 1 degree. Now, with the planet warming inexorably and the threat of long-term climate change looming, some experts are wondering whether the time may one day come when humans want to deliberately attempt such “solar radiation management.” The idea is being investigated by, among others, the National Academy of Sciences, which is conducting research funded by the CIA, NASA and the National Oceanic and Atmospheric Administration. The academy has invited experts to discuss the idea Tuesday. But even considering such an endeavor raises many practical, economical, political and ethical questions, experts said, including what the effects on global and regional climates would be. “I’m not in favor of doing it today. I’m agnostic about whether we should ever do it,” said Alan Robock, a distinguished professor of environmental sciences at Rutgers University. “We don’t have enough information and, in any case, we don’t have the technology.” But Robock said additional research should be conducted despite concerns that determining the feasibility of such “geoengineering” might encourage a government or wealthy individual to try it, and could lessen efforts to curb greenhouse gases such as carbon dioxide. “I don’t think you can just ignore it and pretend it doesn’t exist, and sometime in the future, when someone becomes scared and wants to do it, they don’t even know whether they can do it,” he said. Mount Pinatubo’s eruption sent an estimated 20 million tons of sulfur dioxide and ash <http://earthobservatory.nasa.gov/Features/Volcano/>into the stratosphere, where the sulfur dioxide formed sulfate particles that reflected sunlight back into space. Some believe this could be done effectively and at relatively low cost by injecting an aerosol of sulfur dioxide or some other gas into the atmosphere over a period of time, either from aircraft or powerful missiles. Ken Caldeira, a senior investigator for the Carnegie Institution for Science, told a congressional committee in 2009 that such methods are inexpensive, can be deployed quickly, and probably would cool the Earth effectively. He stressed, however, that it is more important to address the root cause of global warming by reducing the production of greenhouse gases. Carnegie will host a panel discussion on the subject Tuesday evening. But Robock, in an interview, said the effort is “not feasible. No technology exists to do solar radiation management. There are no airplanes, or hoses or missiles that exist to get sulfur up into the stratosphere.” A more limited variation of the idea is to spray sea salt into clouds over the ocean, probably from ships, to form more water droplets in the clouds and make them whiter, said Lynn Russell, a professor of atmospheric chemistry at the Scripps Institute of Oceanography, which is part of the University of California at San Diego. The brighter clouds would reflect more sunlight. _______________ Ken Caldeira Carnegie Institution for Science Dept of Global Ecology 260 Panama Street, Stanford, CA 94305 USA +1 650 704 7212 [email protected] http://dge.stanford.edu/labs/caldeiralab @kencaldeira -- You received this message because you are subscribed to the Google Groups "geoengineering" group. To unsubscribe from this group and stop receiving emails from it, send an email to [email protected]. To post to this group, send email to [email protected]. 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