Infographic
Sunlight reflection methods
Sunlight reflection methods (SRM) are hypothetical approaches to lower global temperatures by increasing the amount of sunlight reflected to space.
Stratospheric aerosol injection (SAI)
WHAT'S THE IDEA?
Tiny particles released in the stratosphere would directly reflect a small fraction of sunlight.
Sunlight
COULD IT WORK?
There is no doubt that SAI could produce a large cooling effect, and it appears feasible to do with new, specially designed, high-altitude jets.
HOW WOULD WE KNOW?
Detailed modeling studies will be essential for evaluating SAI’s climate consequences and potential side effects, and field experiments could help address some uncertainties.
CLIMATE RESPONSE
SAI could produce an even, global cooling effect, reducing many climate change impacts. However it could also produce greater reductions in rainfall in some regions.
SIDE EFFECTS
SAI would delay the recovery of the ozone hole, add somewhat to acid rain, and make the sky a little whiter.
Marine cloud brightening (MCB)
WHAT'S THE IDEA?
Sea salt particles would be sprayed from ships to enhance the reflectivity of low-lying clouds.
COULD IT WORK?
It is possible MCB could be scaled to produce a regional to global cooling effect, but developing effective sprayers is technically challenging and the cloud response is uncertain.
HOW WOULD WE KNOW?
Small-scale field experiments will be essential for evaluating MCB’s feasibility, and climate modeling will be needed to evaluate its potential consequences.
CLIMATE RESPONSE
Models suggest large-scale MCB deployment could decrease temperatures on regional to global scales, while smaller scale efforts might provide local benefits such as short-term relief for heat-stressed ecosystems like the Great Barrier Reef.
SIDE EFFECTS
Uneven cooling of the sea surface could change atmospheric circulation and precipitation patterns.
Marine cloud brightening (MCB)
Stratospheric aerosol injection (SAI)
Sunlight
Tiny particles released in the stratosphere would directly reflect a small fraction of sunlight.
Sea salt particles would be sprayed from ships to enhance the reflectivity of low-lying clouds
WHAT'S THE IDEA?
It is possible MCB could be scaled to produce a regional to global cooling effect, but developing effective sprayers is technically challenging and the cloud response is uncertain.
There is no doubt that SAI could produce a large cooling effect, and it appears feasible to do with new, specially designed, high-altitude jets.
COULD IT WORK?
Detailed modeling studies will be essential for evaluating SAI’s climate consequences and potential side effects, and field experiments could help address some uncertainties.
Small-scale field experiments will be essential for evaluating MCB’s feasibility, and climate modeling will be needed to evaluate its potential consequences.
HOW WOULD WE KNOW?
SAI could produce an even, global cooling effect, reducing many climate change impacts. However it could also produce greater reductions in rainfall in some regions.
Models suggest large-scale MCB deployment could decrease temperatures on regional to global scales, while smaller scale efforts might provide local benefits such as short-term relief for heat-stressed ecosystems like the Great Barrier Reef.
CLIMATE RESPONSE
SAI would delay the recovery of the ozone hole, add somewhat to acid rain, and make the sky a little whiter.
Uneven cooling of the sea surface could change atmospheric circulation and precipitation patterns.
SIDE EFFECTS
Stratospheric aerosol injection (SAI)
Marine cloud brightening (MCB)
WHAT'S THE IDEA?
Tiny particles released in the stratosphere would directly reflect a small fraction of sunlight.
Sunlight
Sea salt particles would be sprayed from ships to enhance the reflectivity of low-lying clouds.
There is no doubt that SAI could produce a large cooling effect, and it appears feasible to do with new, specially designed, high-altitude jets.
It is possible MCB could be scaled to produce a regional to global cooling effect, but developing effective sprayers is technically challenging and the cloud response is uncertain.
COULD IT WORK?
Detailed modeling studies will be essential for evaluating SAI’s climate consequences and potential side effects, and field experiments could help address some uncertainties.
Small-scale field experiments will be essential for evaluating MCB’s feasibility, and climate modeling will be needed to evaluate its potential consequences.
HOW WOULD WE KNOW?
SAI could produce an even, global cooling effect, reducing many climate change impacts. However it could also produce greater reductions in rainfall in some regions.
Models suggest large-scale MCB deployment could decrease temperatures on regional to global scales, while smaller scale efforts might provide local benefits such as short-term relief for heat-stressed ecosystems like the Great Barrier Reef.
CLIMATE RESPONSE
Uneven cooling of the sea surface could change atmospheric circulation and precipitation patterns.
SAI would delay the recovery of the ozone hole, add somewhat to acid rain, and make the sky a little whiter.
SIDE EFFECTS
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