Machine Design

The global warming solution you’re not likely to hear about

As fall elections near, it looks as though voters are about to be subjected to a fresh round of bombast from politicians about energy policy and global warming.

Name calling and the settling of political scores tends to crowd out discussions of the science behind ways of mitigating possible warming effects. With that in mind, it is worth considering an idea from a group known as the Intellectual Ventures Lab. With something dubbed the Stratospheric Shield, they suggest putting sulfur-bearing aerosols into the stratosphere to slightly reduce the amount of sunlight reaching the Earth and, thus, cool the planet. Their inspiration comes from volcanic eruptions, which do the same thing naturally.

It might be easy to dismiss IV’s Shield as a crackpot notion except that it comes from researchers with heavy-duty credentials. IV itself was founded by Nathan Myhrvold and Edward Jung, former Microsoft Corp. chief technology officer and chief software architect, respectively. The IV team that came up with the Shield includes Ken Caldeira, who contributes research to the Intergovernmental Panel on Climate Change, an entity which earned a Nobel prize for its work on global warming. The Stratospheric Shield even got its own section in economist Steven D. Levitt’s Superfreakonomics because it promises to be an inexpensive way of solving a seemingly intractable problem.

And inexpensive it certainly is. IV figures just five base stations could pump enough SO2 in the stratosphere to cool the planet. (The amount of SO2 would be less than 1% of current worldwide sulfur emissions.) The stations would cost about $150 million to set up and $100 million annually to operate. As Levitt points out in Superfreakonomics, if IV’s idea works, it would cost $50 million less to stop global warming than what Al Gore’s foundation is paying just to increase public awareness of it. In contrast, some mainstream economists have proposed spending $1.2 trillion (yes, with a “t”) annually, funded by taxes on carbon output, as a way of accomplishing the same goal.

IV says they aren’t currently working on the Shield idea but they have fleshed out the basics of it. Each base station would liquefy SO2 (through well-known processes) and send it up an 18-mile-long lightweight hose. The hose could have a diameter of just a couple inches. Helium-filled balloons positioned every few hundred yards would hoist it into the stratosphere. To keep pressures down, small pumps every 100 yards would push the liquid to the top of the hose, where nozzles would mist it into the stratosphere. There high winds would distribute it around the planet in about 10 days’ time.

The biggest slam against IV’s Shield is that it intentionally alters the Earth’s natural state. To this, IV researchers point out that humankind already alters Mother Nature every time a commercial jet spews exhaust at 30,000 feet or when a smokestack goes live.
Cynics, though, will probably suspect there’s another reason some might wish the Shield concept would just go away: Solving the perceived global warming problem would put an end to the gravy train of grant money now spent studying it.

— Leland Teschler, Editor

© 2010 Penton Media, Inc.

Hide comments


  • Allowed HTML tags: <em> <strong> <blockquote> <br> <p>

Plain text

  • No HTML tags allowed.
  • Web page addresses and e-mail addresses turn into links automatically.
  • Lines and paragraphs break automatically.