The Economist has an article summarising a journal from the Royal Society titled ‘Geoscale engineering to avert dangerous climate change’. There are two basic ways to lower the Earth’s temperature and several ways of achieving both. The article summarises them:
Reducing carbon dioxide in the atmosphere:
- Seed the oceans with iron to increase the growth of plankton. The plankton will absorb carbon dioxide and then, when they die, fall to the seabed taking the CO2 with them.
- Planting more trees, particularly genetically-modified fast-growing trees, to lock up carbon dioxide.
- Turning carbon dioxide into a fuel by using hydrogen. Although we need a way to make the hydrogen without generating carbon dioxide.
Reflecting sunlight back into space:
- Deliberate pollution of the stratosphere with sulphate particles, as these will reflect sunlight.
- Increase the reflectivity of clouds by spraying them with seawater.
There are dangers of course, and the Intergovernmental Panel on Climate Change described geo-engineering as “largely speculative and unproven, and with the risk of unknown side-effects”.
The article suggests such projects would need plenty of regulation to look into which regions of the planet will be negatively affected by activity designed to improve other regions. (Via Boing Boing.)