Geoengineering would turn blue skies whiter

[OKIsItJustMe]

19. Even this scheme actually involves some expense

http://en.wikipedia.org/wiki/Stratospheric_sulfate_aerosols_(geoengineering)#Delivery_methods

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[font size=4]Delivery methods[/font]
[font size=3]Various techniques have been proposed for delivering the aerosol precursor gases (H[font size="1"]₂[/font]S and SO[font size="1"]₂[/font]). The required altitude to enter the stratosphere is the height of the tropopause, which varies from 11 km (6.8 miles/36,000 feet) at the poles to 17 km (11 miles/58,000 feet) at the equator.

• Aircraft such as the F15-C variant of the F-15 Eagle have the necessary flight ceiling, but limited payload. Military tanker aircraft such as the KC-135 Stratotanker and KC-10 Extender also have the necessary ceiling and have greater payload.
• Modified Artillery might have the necessary capability, but requires a polluting and expensive gunpowder charge to loft the payload.
• High-altitude balloons can be used to lift precursor gases, in tanks, bladders or in the balloons' envelope. Balloons can also be used to lift pipes and hoses, but no moored balloon has ever been deployed to the necessary altitude.

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http://www.freakonomics.com/2011/09/02/finally-a-garden-hose-to-the-sky/

[font face=Serif][font size=5]Finally: A Garden Hose to the Sky[/font]
Freakonomics
09/02/2011 | 2:37 pm

[font size=3]Well, it’s actually happening. An idea reported extensively in SuperFreakonomics has come to fruition, and some mad scientists are getting their way (and a little government funding) to build a garden hose to the sky — and potentially save the world by cooling it down.

A team of British researchers called SPICE (Stratospheric Particle Injection for Climate Engineering) is trying to pump particles of water into the atmosphere as a test run before moving onto sulfates and aerosols that would reflect sunlight away from earth, mimicking the aftereffect of a massive volcanic eruption. SPICE is building the garden hose at an undisclosed location, with £1.6 million in U.K. government funding and the backing of the Royal Society.

Check out Steven Levitt's interview with Jon Stewart from 2009, where he discusses the idea (beginning at about the 2:20 mark). And below, from SuperFreakonomics Illustrated, is a look at Intellectual Ventures’ plan to pump liquified sulfur dioxide into the stratosphere.



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