February 10, 201511:03 AM ET
The eruption of Mount Pinatubo in the Philippines in 1991 spewed almost 20 million tons of sulfur dioxide into the atmosphere, causing worldwide temperatures to drop half a degree on average.
Arlan Naeg/AFP/Getty Images
Before anyone tries to cool the Earth with technologies that could counteract global warming, there needs to be a lot more research into the benefits and risks. That’s the conclusion announced Tuesday by a scientific panel convened by the prestigious National Research Council to assess “climate geoengineering” — deliberate attempts to alter the global climate.
Geoengineering has been seen as the potential last-ditch option to stave off the worst effects of climate change, given that agreements to reduce greenhouse gas emissions have been slow in coming.
“The central, biggest fear is the fear that just even talking about this, or researching it and popularizing it, will lessen the strength of our commitment to cut emissions. That is the underlying fear.”
– David Keith, climate scientist, Harvard University
The basic idea is simple: Either suck carbon dioxide from the atmosphere or reflect incoming sunlight away from Earth.
But the prospect of intentionally mucking with the world’s climate is hugely controversial. Until recently, even discussing it has been somewhat taboo among scientists. One fear is that nations might fight to control the global thermostat — unilaterally taking action to try to adjust temperatures to their liking.
Another is that the promise of a quick geoengineering fix would discourage the world from doing the hard work needed to actually reduce greenhouse gas emissions.