Blocking the Sun Is No Plan B for Global Warming (David Biello, Scientific American , Dec. 9, 2016)
Today we review an assessment of attempting to reduce global warming by directly reducing incoming sunlight for the entire globe by artificial means, known as geoengineering. In view of the failure of many countries to take action to mitigate climate change, the challenge to reduce carbon emissions has gone to the point (to reduce by 3%/yr or more) where many feel that taking direct action through geoengineering is the only solution. The author warns though that doing this may produce inadvertent disasterous results as well as giving relief to the very modest efforts currently being made to reduce CO2 emissions.
“Planet-wide geoengineering schemes might work—or backfire. Either way, there is no getting around the need to reduce CO2 in the atmosphere”
“Geoengineering is also part of the appeal of big physics, once reserved for hydrogen bombs and subatomic particles. Figuring out how droplets of sulfuric acid sprayed into the stratosphere might offset rising CO2 offers physicists a chance to have a literal global impact”
“The incredibly slow progress in combating climate change worldwide—the Paris talks are the 21st attempt to reach international agreements in the past 25 years—raises the appeal of the seemingly quick fix of seeding the sky.”
“geoengineering could have unintended consequences worse than climate change itself or end up exacerbating the underlying problem of too much CO2 by mistakenly taking the pressure off to reduce fossil fuel burning.”
“The secret to combating climate change is not some lever to tilt Earth's energy balance but rather to be flexible, to build a system of replaceable parts with as many mutually reinforcing connections as possible to fend off a single, catastrophic failure—in a word, resilience, like that of life itself on this planet and how biology and geology conspire to create the air.”