Solar radiation management is increasingly considered to be an option for managing global temperatures1,2, yet the economic effects of ameliorating climatic changes by scattering sunlight back to space remain largely unknown3. Although solar radiation management may increase crop yields by reducing heat stress4, the effects of concomitant changes in available sunlight have never been empirically estimated. Here we use the volcanic eruptions that inspired modern solar radiation management proposals as natural experiments to provide the first estimates, to our knowledge, of how the stratospheric sulfate aerosols created by the eruptions of El Chichón and Mount Pinatubo altered the quantity and quality of global sunlight, and how these changes in sunlight affected global crop yields. We find that the sunlight-mediated effect of stratospheric sulfate aerosols on yields is negative for both C4 (maize) and C3 (soy, rice and wheat) crops. Applying our yield model to a solar radiation management scenario based on stratospheric sulfate aerosols, we find that projected mid-twenty-first century damages due to scattering sunlight caused by solar radiation management are roughly equal in magnitude to benefits from cooling. This suggests that solar radiation management—if deployed using stratospheric sulfate aerosols similar to those emitted by the volcanic eruptions it seeks to mimic—would, on net, attenuate little of the global agricultural damage from climate change. Our approach could be extended to study the effects of solar radiation management on other global systems, such as human health or ecosystem function.

Spraying a veil of sun-dimming chemicals high above the Earth to slow global warming could harm crop yields in an unintended side-effect of turning down the heat, U.S. scientists said on Wednesday.

Some researchers say a man-made sunshade, perhaps sulfur dioxide released high in the atmosphere, could limit rising temperatures and the after-effects like the wildfires that have ravaged California and Greece this summer.

But a U.S. scientific team found that big volcanic eruptions, such as Mount Pinatubo in the Philippines in 1991 and El Chichon in Mexico in 1982, cut yields of wheat, soy and rice after spewing sun-blocking ash that blew around the world.

DonDeeHippy wrote on Aug 10^th, 2018 at 5:48am:



You mean like reducing CO2 to about 280ppm?

Despite the facts we are getting better crops at 400ppm? More food for a burgeoning population doesn't interest you?

Lol when have  I ever quoted that Lee ?
I don’t think I’ve ever said much at all about co2
Why do feel the need to put words in my mouth.

As I’ve stated before I’m more worried about all the poisons fossil fuel produce, I’m still undecided on co2

I don’t think we have to worry about lowing co2 levels for awhile so I think our crops r safe

I think removal of changes is the best answer, not more potential screwing up

Stop burning fossil fuels for 1, Stringent filtering on manufacture, reclamation of barren land , elimination of chemicals to grow food.

Sounds like u want them to make the sun shade, I'm confused, did u post this,  for or against Lee ?

Finally some scientists seem to be looking at unintended consequences.