Enhance your albedo and save the world; algae with high hopes?
CHARLES J. HANLEY
Nov. 08, 1997
You mean that driveway of yours still isn't painted white? What about the roof? And the backyard algae pond _ still but a dream?
Sounds like you've done precious little to stop global warming. Keep it up and we'll have no choice but to roll out the giant dust guns, launch the 55,000 space mirrors, and start packing dry ice into mountain-sized snowballs.
Climate change tops the world agenda these days as negotiators try to nail down a multinational treaty to limit consumption of oil and other fossil fuels, which spew heat-trapping carbon dioxide into the atmosphere.
But while policymakers and mainstream researchers have painstakingly worked out proposals for cutting back fuel use, other scientists have roamed farther afield in search of more pain-free ``techno-fixes'' to the threat of global warming.
Some notions are bizarre _ storing carbon dioxide as dry ice in 1,300-foot-high refrigerated globes, for example. Some are feeble _ planting trees on your lawn. And some are downright dangerous _ a Japanese auto executive wants people to drive faster, since briefer trips emit less carbon dioxide.
But other research, some financed by oil companies and utilities, has an aura of feasibility that troubles environmentalists.
``It's the kind of thing that frightens me because it is an excuse to do nothing on the consumption side,'' worries Ben Matthews, a British environmental scientist.
Gregory Benford, on the other hand, thinks it's the would-be fuel regulators who are being unrealistic, since Americans, the No. 1 emitters, seem unlikely to trade down from their gasoline-gulping vehicles.
``We don't have a prayer of solving this problem by restraint and turning everybody into energy cops,'' said Benford, a physicist at the University of California-Irvine who champions more research into unorthodox ideas.
For what they're worth, some of the simplest ideas might be tried at home _ making paved surfaces light-colored, for example.
Scientists say improving Earth's ``albedo,'' its reflective power, to deflect 1 percent more sunlight might be enough to counteract warming. But an open Internet exchange between an American and a Swede illustrated one potential problem.
``Install white roof shingles on your house instead of black,'' the helpful American suggested.
``In Sweden ... if we tried to reflect the heat we would have to have more heating, increasing emissions,'' came the response.
Well, then, how about albedo on a bigger scale?
Some propose launching vast sheets of foil into orbit. The U.S. National Academy of Sciences studied one idea, for 55,000 space mirrors, and estimated it might cost a stunning $120 billion a year to launch and maintain. Besides, Matthews points out, ``space shades'' inevitably would cool some regions that don't need or want it.
Other researchers favor a subtler approach, a reflective layer of dust across the stratosphere.
The National Academy found two ``delivery systems'' potentially economical: 16-inch battleship guns firing shells packed with the dust 12 miles straight up, and jetliners emitting particulates from their engines as they crisscross the skies.
This dusty shell would make for fiery sunsets. But its more sinister effects are less predictable, including possible harm to the atmosphere's all-important ozone layer.
Some of the most serious work _ and money _ is going into research on disposing carbon dioxide.
The U.S. utilities' Electric Power Research Institute is investigating ways of liquefying or solidifying carbon dioxide from power plants and pumping it to the ocean floor. But the dense plume clearly would kill marine life and raise a question: When might nature churn the gas back into the atmosphere?
Other experimenters are fertilizing huge patches of ocean with iron, setting off an explosive growth of algae, which absorb carbon dioxide from the sea and, ultimately, the atmosphere. But the potential for throwing nature out of balance unnerves some.
``These techno-fixes rely on all this technology continuing to be available and nothing going wrong,'' Matthews said. ``It's passing the risk to future generations.''
But Benford contends we're destined to be planetary handymen.
``Most people don't want to consider actively managing the globe,'' said the physicist, a prolific science fiction writer. ``But we have to eventually become stewards of the Earth, the whole Earth.''
And if the treaty talks fail, he maintained, we'll be on our way.