The potentially dangerous unintended consequences of tampering with the earth’s climate lead some to argue for a new UN global agreement to prevent any future manipulation of the global climate system. Countries unilaterally (or maliciously) undertaking programs to change the climate is a particular cause of concern. But The New York Times’ John Tierney thinks geoengineering is a real option, arguing that “political leaders will not seriously reduce carbon emissions anytime soon.”
Geoengineering, or “climate engineering,” is increasingly viewed as a practical option for addressing climate change, according to The New York Times. A few recent studies argue that geoengineering may be technically feasible and more cost-effective than global mitigation and adaptation work.
The U.S. National Academy of Sciences held a two-day seminar on geoengineering in June and will soon release a report. Britain’s Royal Society is also looking into options. According to Real Climate, John Holdren, President Obama’s chief Science Advisor, has said geoengineering “has to be examined as a possible response to global warming.” The Obama administration has promised to review upcoming research. (The New York Times notes, however, that no significant R&D has been put towards geoengineering.)
The science research site, Novim, has published a report, “Climate Engineering Responses to Climate Emergencies,” on the use of “aerosol particles to reflect shortwave solar radiation back into space.” Researchers associated with the project have argued that USD 100 million could be enough to test small-scale geoengineering, perhaps over the Arctic. Aerosol particles could be expelled into the stratosphere to reproduce the effects of particle matter released from volcanic eruptions. The New York Times says the eruption of Mt. Pinatubo in 1991 resulted in a cooling of the global climate by 1 degree Fahrenheit. ” Just as occurred after that eruption, the effects would wane as the particles fell back to Earth.” In a recent edition of Science, other scientists looked to the same eruption and consequent cooling and saw a cause for concern — after the Mt. Pinatubo eruption, worldwide precipitation rates fell. Massive aerosol use could lead to droughts.
Other geoengineering strategies being explored include “air-capture” machines that would strip C02 out of the atmosphere (see earlier post), as well as spraying seawater mist up to low-lying clouds, creating brighter and more reflective clouds. A recent report by the Copenhagen Consensus Center, “Engineer a Better Climate,” found cloud-brightening technology to be a potentially viable option. According to the Copenhagen Consensus Center, “marine cloud whitening with a fleet of unmanned ships would be extremely cheap: for about $9 billion, all of the global warming for the century could be avoided, with benefits adding up to about $20 trillion.” The Web site, Real Climate, is dismissive of the report’s findings: “In this report, they simply omit the costs of many of the potential negative aspects of producing a stratospheric cloud to block out sunlight or cloud brightening, and come to the conclusion that these strategies have a 25-5000 to 1 benefit/cost ratio.”
Geoengineering continues to face skepticism. According to Real Climate, geoengineering schemes fail to address the negative impact of rising CO2 levels on the environment, and “ignore the effects of ocean acidification from continued CO2 emissions, dismissing this as a lost cause. Even without global warming, reducing CO2 emissions is needed to do the best we can to save the ocean. The costs of this continuing damage to the planet, which geoengineering will do nothing to address, are ignored in the analysis in this report. If it [geoengineering] were stopped, by the loss of interest or means by society, the resulting rapid warming would be much more dangerous than the gradual warming we are now experiencing.” Real Climate concludes in its review of the Copenhagen Consensus Center research: “The real consensus, as expressed at the National Academy conference and in the AMS statement, is that mitigation needs to be our first and overwhelming response to global warming, and that whether geoengineering can even be considered as an emergency measure in the future should climate change become too dangerous is not now known.” (Read more of Real Climate’s views on the report.)
Image credit: John MacNeill / Copenhagen Consensus Center