Suppose for a minute—which is about 59 seconds too long, but that's for another column—that global warming poses an imminent threat to the survival of our species. Suppose, too, that the best solution involves a helium balloon, several miles of garden hose and a harmless stream of sulfur dioxide being pumped into the upper atmosphere, all at a cost of a single F-22 fighter jet.

Good news, right? Maybe, but not if you're Al Gore or one of his little helpers.

The hose-in-the-sky approach to global warming is the brainchild of Intellectual Ventures, a Bellevue, Wash.-based firm founded by former Microsoft Chief Technology Officer Nathan Myhrvold. The basic idea is to engineer effects similar to those of the 1991 mega-eruption of Mt. Pinatubo in the Philippines,...