Thursday 17 December 2009

Strato Shield and Geoengineering: hurrah!

There's an episode of "The Simpsons", where invasive lizards are found to be an effective predator of pigeons in Springfield (S10:3, "Bart The Mother").  Principal Skinner and Lisa have the following conversation:

Skinner: Well, I was wrong. The lizards are a godsend.
Lisa: But isn't that a bit short-sighted? What happens when we're overrun by lizards?
Skinner: No problem. We simply release wave after wave of Chinese needle snakes. They'll wipe out the lizards.
Lisa: But aren't the snakes even worse?
Skinner: Yes, but we're prepared for that. We've lined up a fabulous type of gorilla that thrives on snake meat.
Lisa: But then we're stuck with gorillas!
Skinner: No, that's the beautiful part. When wintertime rolls around, the gorillas simply freeze to death.

I thought of this when reading of the concept of spraying aerosol of Sulphur Dioxide into the atmosphere, to reduce Carbon Dioxide induced global warming.  Geoengineering, with the Stratoshield.  Lisa: But isn't that a bit short-sighted?  What happens when we're overrun with Acid rain?
"No problem, we simply release wave after wave of alkalines into the oceans, they'll wipe out the acid rain".  Lisa: but aren't the alkalines even worse?  “Yes, but we’re prepared for that, we’ve lined up some more SO2 to cool down and re-balance the oceans".  Lisa: But what if we get it wrong and it's too cold?  "No, that's the beautiful part, when winter rolls around we simply freeze to death …"  Al Gore has weighed in on the concept: “in a word, it’s nuts”.
But here’s the real beautiful part: it would probably work!  And it would work quickly.  We have a pretty good idea of what happens when we have increases in SO2 into the atmosphere, from the eruption of Mt Pinatubo in the Philippines in 1991.  That led to worldwide reductions in temperatures of a few degrees for a few years.  The SO2 precipitated out in 2-3 years, but in such small quantities that it did not add to ocean acidity.
I’d heard about geoengineering some time ago on the radio, but thought at the time that it sounded rather like crazy science, “nuts” as Gore said.  But I took a closer look, thanks to Super Freakonomics.  I think I bagged the book a little prematurely in my earlier post, for it’s worth the price of purchase just to read the chapter on the global warning debate and issues (“Why is Al Gore like Mount Pinatubo?”). 
That chapter covers at the Stratoshield concept (aka "Budyko's Blanket), and some others as well: like the use of ocean spray to help promote localized cloud cover, which can help to cool the globe.  I’d said that SF was thin gruel, but this chapter is a hearty stew.
Who’s promoting the idea?
Intellectual Ventures: set up by Nathan Myhrvold in 1990.  Myhrvold was the technical and strategic guy at Microsoft for many years, described by Bill Gates as “the smartest guy I know”.  He has set up IV to develop ideas and concepts, to register patents and see them commercialised.  Others involved in the project have strong green credentials: Ken Caldeira,  John Latham, et al.   
Benefits:
1.     Quick fix: to put out the fire while we work out fire-control measures.
2.     Simple: can be done with existing technology.
3.     Cheap: would only cost in the tens of millions, vs. the trillions per year that are being       mooted to get the world “carbon free”.
4.     Stop-gap: can be deployed for only as long as needed then can be dismantled within a few months.
5.     Place-specific: can be situated at the poles where the temperatures are rising at four times the rate of the poles.   Can keep the polar regions, especiall the Arctic, at pre-industrial levels of ice cover.
Objections:
1.     Diversion: In doing so, we risk diverting attention from the need to reduce the amount of carbon in the atmosphere.  But as Nathan Myhrvold says, that’s like criticizing the doctor for doing a heart by-pass on a patient that should have exercised more and eaten more sensibly.
2.     Acid rain: the amount of SO2 needed is one one-thousandth (IV) or one two-thousandth (Freakonomics) of the amount that goes into the air every year, from natural and man-made sources (about 50/50).  One of the options in any case, is to pump the SO2 already been released by power stations further into the troposphere by long light plastic chimney tunnels.  
3.     Technical issues: is it practicable?  Well, the smart guys at Intellectual Ventures think so and have written a White Paper to show how.  Testing the concept would be in the millions or tens of millions of dollars, mere fractions of the billions being discussed for global warming amelioration.