Nathan Myhrvold, the former chief technical officer at Microsoft, wants to build an artificial volcano. Mt Pinatubo in 1991 became the best studied large volcanic eruption in history, it put more sulfur dioxide into the stratosphere than any volcano since Krakatoa in 1883. There is no longer any dispute that stratospheric sulfur dioxide leads to more diffuse sunlight, a decrease in the ozone layer, and a general cooling of the planet. What was astonishing was how little stratospheric sulfur dioxide was needed. If you injected it in the arctic where it would be about 4 times more effective, about 100,000 tons a year would reverse global warming in the northern hemisphere. That works out to 34 gallons per minute, a bit more than what a standard garden hose could deliver but much less than a fire hose. We already spew out over 200,000,000 tons of sulphur dioxide into the atmosphere each year, but all of that is in the lower troposphere where it has little or no cooling effect, the additional 100,000 tons is a drop in the bucket if you're looking at the tonnage, but it's in the stratosphere where its vastly more effective.
Myhrvold wasn't suggesting anything as ambitious as a space elevator, just a light hose 2 inches in diameter going up about 18 miles. In one design he burns sulfur to make sulfur dioxide, he then liquefies it and injects it into the stratosphere with a hose supported every 500 to 1000 feet with helium balloons. Myhrvold thinks this design would cost about 150 million dollars to build and about 100 million a year to operate. In another design that would probably be even cheaper he just slips a sleeve over the smokestack of any existing small to midsize coal power plant in the higher latitudes and uses the hot exhaust to fill hot air balloons to support the hose.
If Myhrvold's cost estimate is correct that means it would take 50 million dollars less to cure global warming than it cost Al Gore to just advertise the evils of climate change. But even if Myhrvold's estimate is ten times or a hundred times too low it hardly matters, it's still chump change. In a report to the British government economist Nicholas Stern said that to reduce carbon emissions enough to stabilize global warming by the end of this century we would need to spend 1.5% of global GDP each year, that works out to 1.2 trillion (trillion with a t) dollars EACH YEAR.
One great thing about Myhrvold's idea is that you're not doing anything irreparable, if for whatever reason you want to stop you just turn a valve on a hose and in about a year all the sulfur dioxide you injected will settle out of the atmosphere. And Myhrvold isn't the only fan of this idea, Paul Crutzen won a Nobel prize for his work on ozone depletion, in 2006 he said efforts to solve the problem by reducing greenhouse gases were doomed to be “grossly unsuccessful” and that an injection of sulfur in the stratosphere “is the only option available to rapidly reduce temperature rises and counteract other climatic effects”. Crutzen acknowledged that it would reduce the ozone layer but the change would be small and the benefit would be much greater than the harm. And diffuse sunlight, another of the allegedly dreadful things associated with sulfur dioxide high up in the atmosphere, well..., plant photosynthesis is more efficient under diffuse light. Plants grow better in air with lots of CO2 in it also, but that's another story.
But maybe things are improving. In a report issued on March 28 the National Academies of Sciences, Engineering, and Medicine said the US should spend at least $100 million on Geoengineering research, specifically on injecting aerosols into the upper atmosphere to reflect more sunlight and cool the planet. Although constantly screaming about how global warming will lead to a world ending holocaust environmentalist refuse to even consider such a solution; even though in the entire history of life there has never been 8 billion animals as large as human beings alive at the same time, they seem to think all 8 billion people can be made to be happy and healthy without changing the overall biosphere one teeny tiny bit, and all can be accomplished with just moon beams or somesuch. But then environmentalists are not serious people. Bernie Sanders for example doesn't even want to talk about such a thing and says Geoengineering should be grouped with other ridiculous ideas that "obviously" won't work, such as nuclear power, he says global warming is leading the entire human race straight to extinction but we shouldn't even think about Geoengineering as a solution because it might be dangerous. That's about what I would expect him to say because Bernie Sanders is an environmentalist, and environmentalists are not serious people.