The ‘Geo-Engineering’ Scenario

Geo-engineering cannot replace emissions reductions. The less CO₂ you have to balance with sulfates, the more effective geo-engineering would be. But reducing CO₂ emissions by, say, substituting solar and nuclear for coal will only delay climate change. Any net emissions will eventually tip the atmosphere into dangerous territory. If the world wants a techno-fix for climate change, it must develop ways to capture CO₂ from the air and seas.

Researchers are trying, but they have less financial support than producers of corn-based ethanol (which does next to nothing to help climate change). Still, one company is developing a system in which plastic mesh sheets blowing in the wind capture CO₂ from the air. When saturated with CO₂, the sheets are doused with sodium carbonate, yielding harmless baking soda, after which they can be reused. Another approach would remove hydrochloric acid from seawater, which would make oceans less acidic and thus able to absorb more CO₂. About 100 treatment plants could reduce the CO₂ entering the atmosphere by 15 percent, scientists report in the journal Environmental Science & Technology; 700 could offset all CO₂ emissions.

Neither method is ready to go. Without more funding, they never will be, though Richard Branson's $25 million prize for carbon capture is an incentive. If we don't want to resort to the climate solution of last resort, it's time to stop pretending that changing light bulbs and driving hybrids will be enough to prevent dangerous climate change.

© 2007