Smoke and mirrors to slow global warming?

October 27, 2008

With worries about recession in many countries, does it make sense to try out some more radical ideas for fighting global warming, like placing mirrors in the sky to block the sun or fertilising the oceans to soak up greenhouse gases?

They sound like great proposals at first sight: simple,  probably cheaper and in some cases reversible. See a story about the technologies here. But there’s a lot of scepticism among scientists in the U.N. Climate Panel — there could be nasty side effects.

If you spew clouds of tiny particles, such as sulphur, into the upper atmosphere to block out some sunlight, for instance, they will eventually fall to earth and add to smog (think Beijing on bad days before the Olympics). Backers say that volcanoes do the same thing naturally — big eruptions can cool the planet. But who wants to breathe it in every day?

You can also dump iron filings into the seas to spur a bloom of algae which absorb carbon dioxide from the atmosphere and then sink to the bottom when they die and cut the amount of the greenhouse gas in the atmosphere. Sounds great, but it might also make the oceans more acidic — shellfish, crabs, lobsters, etc could then find it harder to build shells and so be more vulnerable to predators.

And if you put a giant barrier in space to reflect sunlight it might cause all sorts of havoc with the climate.

Time Magazine once called such “geo-engineering” options the “Hail Mary pass” – a desperate throw that just might win you the match. 

Is it worth the risk?


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My anti-spam word to post this comment was “toast”. Rather appropriate as that could well describe conditions here on Earth in the near future. Recent developments leave me feeling ambivalent. Consumer driven economies have been showing signs of slowing down over the past year. Demand for fossil fuels, metals and other commodities has declined, unfortunately because of an economic catastrophe. While good for the environment, this calamity could lead Nations to desperate actions. Case in point, the rise of fascism in Europe in the 1930s during the Great Depression which lead to World War II. Conservation and the sustainable use of resources are the immediate solutions as future technologies are uncertain. We in the industrialized nations must learn to live with much less. We must quickly change the way we eat; produce goods; use energy, water and land. At the same time the great challenge is to find ways to bring prosperity to all of humanity. In short,to lift up our brothers and sisters around the world. If we do not succeed at this task, how will we live in peace and sustain ourselves.

Posted by Anubis | Report as abusive

The idea that these are even being considered rationally is amazing. What’s next? a tin foil helmet for every environut? It seems like they want to put a dunce cap on the world rather than bother doing it invididually. Environmentalists are funny sometimes. I still laugh every time I heard “climate change” because global warming has too much evidence against it, so instead of warming, now ALL weather is proof humans are bad good fear mongering.

Posted by Ben | Report as abusive