Solar Geoengineering Could Lead To Whiter, Brighter Skies

cylonlover writes "We've heard reports that placing small, reflective particles into the upper atmosphere could actually improve crop yields, but would also significantly reduce the amount of electricity generated by solar power plants and do little to arrest the acidification of the world's oceans. Now another potential side effect has been theorized by Californian researchers, who say that solar geoengineering could lead to brighter, whiter skies, and sunsets with an afterglow (abstract)."

Re:Sounds like the cons outweigh the pro's.

[danlip]

This idea should be considered idiotic :)

Clearly the correct (and most feasible) approach to us putting too much CO2 into the atmosphere is to put less CO2 into the atmosphere, not embark on some other massive experiment with mother nature whose outcome we can't really predict. Between solar, wind, and nuclear it's not hard to do, it's just not very popular with the big oil interests that control our politics.

As someone in solar science...

[sugarmatic]

...I have to say this is a really stupid idea. It would absolutely prevent ground-based solar observation of the corona, important to astrophysical studies and space weather. To give an idea of how difficult it is already, one must image or analyze brightness levels on the order of a millionth of the brightness of the solar disk to do real science, on time scales of five minutes or less, at very narrow wavelength bandwidths. There simply aren't enough photons to average out the noise with sky brightness levels above around 20 ppm on time scales that are meaningful, and detector noise makes measurements above 30 ppm sky brightness pretty much futile.

There are not very many places on earth with the necessary to make even part-time measurements as it is.

The night time folks will be screwed as well.

The winners will be a few large multinational corporations with the funds to corrupt policy. The losers will be the rest of us.

Re:The haze is white in the city, violet from afar

[malhombre]

I grew up in the hills of southern California in the 60s. That was before much had been done to improve air quality. We had the most beautifully colored sunsets back then. Of course, some fool had to go and ruin it all for me by explaining the fact that all those amazing colors were sinister poisonous gases and not some awesome gift of nature. Then one day I flew into LA and down through a cloud of nasty brownish gray smog that made me want to hold my breath until we landed. So much for the magic of childhood.

Re:If you dump al that light on crops,

[Khyber]

"Photosynthesis is more effective in diffuse light."

No, it's really not. Chlorophyll has a neat mechanism by which light tends to (usually) work in one direction. You can test this for yourself. Obtain a test tube of chlorophyll in a suspended liquid solution. Take an incandescent light. If you put the test tube directly between you and the light at eye level, you will see it as mostly red. Any other direction, you see it as green.

Also, making the skies BRIGHTER (as per TFS and TFA) means increasing photon flux density. The current limit for most plants to withstand light falls between 1500-1800umol. After that, you rapidly begin approaching photosynthetic poisoning (AKA bleaching0 of plant tissues. Many food crops, especially vegetative ones, don't tolerate very high light levels. Most lettuces prefer roughly 300-600 umol, and start doing undesirable things at anything much higher, like bolting and not creating a compact head, or outright turning white.

This is one of the worst ideas I've heard coming from Californian scientists in a long long time. Makes me glad to be working with better-educated European horticultural companies.