Can we engineer Earth's atmosphere to stop global warming?
In 1991, Mount Pinatubo erupted in the Philippines, blasting 20 million tons of sulfur dioxide into the stratosphere. The particles formed a haze around the Earth that filtered out sunlight and temporarily cooled average global temperatures by 1 degree.
When Thomas Schelling, a Nobel Prize-winning economist at the University of Maryland, thinks about this volcanic eruption, he doesn’t think disaster. He sees an opportunity to combat global warming.
“The basic science of what is now called solar radiation management – which is masking a little bit of the incoming sunlight – that’s been understood for more than 100 years,” Schelling said.
In place of volcanoes cooling the Earth, Schelling envisions airplanes or rockets spraying sulfur dioxide gas into the stratosphere to block the sun’s rays. Sulfur dioxide is cheap, because it’s a pollutant that rises from the smokestacks of coal-fired power plants.
“The estimate is that if you wanted to block out a percent or so of incoming sunlight… the cost is so small that maybe 30, 40, 50 countries could afford to do it on their own,” Schelling said. “Unlike a big global effort to reduce emissions, where no single country could gain by drastically reducing emissions all by itself, and where you need international cooperation or coercion to make it happen.”
What Schelling is describing is geo-engineering. It’s the proposed use of technology to alter the world’s climate to counteract global warming, without the much more politically difficult changes required to stop burning fossil fuels.
In a time of Congressional gridlock and an inability of world governments to work together on climate change, a number of scientists are looking into geoengineering as a kind of Plan B to for humanity that must be explored for pragmatic reasons.
The billionaires Bill Gates and Richard Branson are funding research into a “technofix” for global warming, as are the oil companies Exxon and BP.
Other schemes being tested on a limited scale include dumping iron dust into the oceans to spur algal blooms that consume carbon dioxide. Huge machines could filter carbon dioxide out of the air, or stash it in caverns underground. Spraying seawater or sodium iodide into the air could create or thicken clouds that reflect sunlight.
Wil Burns is former Associate Director of the Energy, Policy, and Climate program at Johns Hopkins University and author of a book called “Climate Geo-Engineering.”
Burns warns of the dangers of unintended consequences. For example, pumping sulfur dioxide into the stratosphere could cool off some areas – but cause deadly droughts in others. Also, he says a sulfur dioxide stratoshield would only temporarily mask the warming problem – not solve underlying cause, pollution, which would quietly continue to get worse even as things seemed to be getting better, Burns said.
“The peril is if you stop,” Burns said. “If that were to happen, then all of the buildup in greenhouse gases that had occurred in the interim would all of a sudden manifest themselves in a huge what we call carbon pulse. You might see temperatures increase between five and 10 times greater than they would have if you did not institute a geoengineering solution. You’re imperiling the existence of life on earth.”
Burns added there is something troubling about the idea that, ‘well, we can’t stop polluting. So let’s just pollute more to cover up our pollution.’
“There’s a sense of hubris, right?” Burns said. “We reached this point because of our inability to really effectively control technological developments, and we’re simply going to use another technological fix. There seems to be an almost irrational sort of confidence in our ability to develop these things and wholly understand their long-term ramifications.”
And there’s another risk. A sustained, well-funded research effort into geoengineering could create a new industry with its own political momentum and lobbying for jobs that could be hard to stop.
The more people fixate on a technofix, the more excuse they have to keep burning fossil fuels.
………………………………
The Environment in Focus is independently owned and distributed by Environment in Focus Radio to WYPR and other stations. The program is sponsored by the Abell Foundation. The views expressed are solely Tom Pelton's. You can contact him at [email protected].