MNN - Mother Nature Network

There have been plenty of crazy ideas thrown around over the past few years on how we can combat global warming. Geoengineers have developed elaborate plans to do everything from dumping iron in the oceans to spur the growth of CO2-gobbling plankton to releasing large amounts of sulphur into the air to reflect sunlight back into space to erecting large sun shields in space to keep the suns rays from hitting us in the first place.

The Telegraph (UK) wrote a story about this last idea, putting solar reflectors into space to block solar rays, and managed to completely screw up just about every important detail in the story. The current version of the story (and it could be updated anytime) says that the plan would require $350 trillion and a gun with a barrel .6 miles across to work, numbers putting the plan squarely into the camp of crazy talk.

Those numbers tripped my BS alarm and I placed a call to the scientist behind the plan, University of Arizona professor Roger Angel, to get the real scoop.

Dr. Angel laughed when I told him about the $350 trillion price tag and .6 mile wide gun that the Telegraph reported. His plan would actually require $5 trillion and the gun used to shoot the sun shields into space would only be about a meter wide. $Five trillion is still a lot of money, but if it's spread out over 50 years (the expected lifetime of the sun reflectors), it comes out to $100 billion a year. We have been spending more that much in our stupid war in Iraq every year and all we get out of that is a lot of death and destruction. Dr. Angel's plan would chop off 2 percent of the sun's incoming rays and in the right set of circumstances, could save the world.

Some critics of geoengineering find fault with the use of resources that could better be used to boost our use of renewable energy to cut down on the release of greenhouse gases, a critique that Dr. Angel acknowledges and actually embraces — he is currently working on technology that would boost solar panel output with the use of concentrator lenses.

It's more important to get ourselves weaned off of fossil fuels right now than to work on plans to engineer the globe back a few degrees. At the same time, though, we shouldn't completely abandon visionary (OK, some may say crazy) schemes for quickly cooling the planet. We could find ourselves faced with rapidly rising levels of CO2 (permafrost melts, releasing massive amounts of dormant CO2 which causes more melting, causing more CO2 to be released, rinse and repeat) and having a few good, technically plausible ideas for reacting just as quickly might be a smart idea.

Here's a video from the Telegraph that actually gets everything right and explains the whole thing pretty well. Someone over there needs to get their facts checked and fix the errors in the story.