Geoengineering: A whiter sky

One idea for fighting global warming is to increase the amount of aerosols in the atmosphere, scattering incoming solar energy away from the Earth's surface. But scientists theorize that this solar geoengineering could have a side effect of whitening the sky during the day. New research from Carnegie's Ben Kravitz and Ken Caldeira indicates that blocking 2% of the sun's light would make the sky three-to-five times brighter, as well as whiter. Their work is published June 1st in Geophysical Research Letters, a journal of the American Geophysical Union.

Carbon dioxide emissions from the burning of coal, oil, and gas have been increasing over the past decades, causing the Earth to get hotter and hotter. Large volcanic eruptions cool the planet by creating lots of small particles in the , but the particles fall out within a couple of years, and the planet heats back up. The idea behind solar geoengineering is to constantly replenish a layer of small particles in the stratosphere, mimicking this volcanic aftermath and scattering sunlight back to space.

Using advanced models, Kravitz and Caldeira—along with Douglas MacMartin from the California Institute of Technology—examined changes to sky color and brightness from using sulfate-based aerosols in this way. They found that, depending on the size of the particles, the sky would whiten during the day and sunsets would have afterglows.

Their models predict that the sky would still be blue, but it would be a lighter shade than what most people are used to looking at now. The research team's work shows that skies everywhere could look like those over urban areas in a world with this type of taking place. In urban areas, the sky often looks hazy and white.

"These results give people one more thing to consider before deciding whether we really want to go down this road," Kravitz said. "Although our study did not address the potential psychological impact of these changes to the sky, they are important to consider as well."

There are several larger environmental implications to the group's findings, too. Because plants grow more efficiently under diffuse light conditions such as this, global photosynthetic activity could increase, pulling more of the greenhouse gas carbon dioxide out of the atmosphere. On the other hand, the effectiveness of solar power could be diminished, as less sunlight would reach solar-power generators.

"I hope that we never get to the point where people feel the need to spray in the sky to offset rampant ," Caldeira said. "This is one study where I am not eager to have our predictions proven right by a global stratospheric aerosol layer in the real world."

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Journal information: Geophysical Research Letters

Citation: Geoengineering: A whiter sky (2012, May 31) retrieved 26 June 2019 from
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May 31, 2012
I'll tell you right now, we're not doing this. Ideas like this give people the excuse to believe that it's, 'just fine' to carry on with this inherited ignorance with their blinkers on, focusing only on their primal self interests. Deal with the problem not the consequence!

May 31, 2012
Let's just say I also hope it won't be necessary.

May 31, 2012
Golden Rule for the entire 'Environmentalist' Movement.

May 31, 2012
Golden Rule for the entire 'Environmentalist' Movement

Although that's not really relevant, as people who care about our environment tend to consume less, repair instead of replace and generally base their acts around values other than profit, and are less trusting of the instigators of environmental impact (industry), when compared with your typical ass guzzling ignoramus.

May 31, 2012
How very indicative of New World Order methodology. The problem could be solved by requiring corporate thugs not to bleed the planet dry of everything that isn't nailed down. But, instead, it's decided that the "rank and file" should take the brunt, their pristine skies denied them. By a machination put in place to answer the situation caused by soulless depredations of the corporate rich, without requiring the corporate rich to end their depredations!
And how well this serves another aim of the NWO. It was recognized for some years that many display a response to color. Oranges can create hunger, which accounts for the red, yellow, orange, brown color palette of Reagan Era fast food restaurants. Light blue can stimulate creativity. Wlimintaing this can make much of the populous as accepting as the NWO wants them to be!
But, then, didn't quislings for the NWO insist that it was impossible for a manmade project, like chamtrails, to affect the entire atmosphere?

May 31, 2012
Albuquerquem, NM has been spraying aerosls into atmosphere
for years to test this theory.

As of today, Albuquerque has had the worst fire break outs
in its history.

In conclusion, kick your experimenting hands off atmosphere !

May 31, 2012
Cloud seeding is nothing new and they have been doing it for a while now. You can even see it on a website some locations where they do cloud seeding, spread around the world.

And as i look outside right now sky is bright and white while its raining.

May 31, 2012
Astronomers hate this idea!

May 31, 2012
"Carbon dioxide emissions from the burning of coal, oil, and gas have been increasing over the past decades, causing the Earth to get hotter and hotter."

In spite of all the hype, hand wringing, smoke and mirrors, cheating on a grand scale, and of course models ad nausium over the past 30 years, there still is little substantive evidence to the last part of this quote. In fact, over the same period the evidence that Earth's climate is very insensitive to changing CO2 levels has been building exponentially.

Jun 01, 2012
Don't know about you guys but for me it's simply wrong to pollute the air we breathe and neglect 100% responsibility for our waste.

Jun 01, 2012
They are already spraying aluminum in order to do something like this, it has been proven that over high air traffic areas the soil concentration of aluminum has gone up over 1000% since pre-industrial history.

I didn't believe in chemtrails until I started looking. One day I saw a jet who's contrail was evaporating a few seconds after the plane moved on and then a few minutes later a plane in the same general area who's "contrail" stayed for HOURS and just spread out. So anyone who tries to convince you that chemtrails are imagined is either misinformed or deliberately misleading. And most of the people who believe in chemtrails are also I can say is: think for yourself but consider all possibilities.

Also why is it that the lingering "contrails" or chem trails always seem to form X's and grids when according to route standards there should only be highways with smaller area and not huge blankets of traffic.

Jun 03, 2012
Lots of spraying is already going on in the atmosphere. I've been taking pics of the "geoengineers" in action for months and there is good evidence that programs like this have been implemented over the last 15 years... check out my facebook photo albums for photographic evidence... search for "Max Mogren" on facebook.

Jun 03, 2012
Let's just say I also hope it won't be necessary.
The people already investing into it, because the geoengineering creates safe job positions for various technicians and researchers involved. The job generation is a powerful mechanism of human activity, until the public money are going.

Jun 04, 2012
Let's not do geoengineering. Please. We are nowhere near capable of cleaning it up if it goes south (and it will - nothing is ever as monocausal as some people make it out to be...especially in the environment)

We don't understand most of the processes on this planet nearly well enough to be sure about the impact of such widespread meddling. Artificial particles falling out of the sky in an uncontrolled manner on water reservoirs, arable land, ocean ecospheres, wildlife feeding grounds, being breathed in with every breath we take (deposited in the lungs) ...

If geoengineering doesn't sound stupid then I don't know what does. (And it will give the industry an excuse to keep on doing what it is doing - pumping toxins into the atmosphere because 'someone else is gonna take care of it, right?'

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