Quit Promoting Mad Schemes, New York Times, Blocking the Sun is a Dangerous Climate Gamble
5 hours ago Anthony Watts
A diagram of the geoengineering projects people have proposed to combat climate change. The laws and risks surrounding such projects are still uncertain. (Image credit: Diagram by Kathleen Smith/Lawrence Livermore National Laboratory)
In The New York Times’ (NYT) op-ed, “Turns Out Air Pollution Was Good for Something,” Zeke Hausfather and David Keith argue that because sulfur particles from past industrial pollution once cooled the planet by reflecting sunlight, policymakers should now consider a deliberate version of that process. They suggest aircraft could inject sulfur into the upper atmosphere to mimic the cooling once provided by dirty smokestacks, pointing to volcanic eruptions such as Mount Pinatubo in 1991 as evidence the method would work. This idea is wrong-headed madness. Experience demonstrates geo-engineering ideas such as this have dangerous and unpredictable consequences.
The authors write that “geoengineering the climate in this way is not a new idea,” and claim that “a more modest approach” of maintaining present temperatures with controlled sulfur injections buying the world time for carbon dioxide reductions to continue.
But geoengineering by blocking the sun is a dangerous fool’s errand. First, the potential unintended consequences are enormous and unpredictable. Sulfur dioxide particles injected into the upper atmosphere would scatter sunlight differently depending on latitude. At middle to low latitudes, sunlight passes through less atmosphere, so scattering effects are modest. But at higher latitudes, sunlight travels through more atmosphere, amplifying scattering—just as sunsets turn red because of the increased distance light travels through more air and particles at low sun angles. Injecting reflective particles globally would therefore not create uniform cooling. It would over-cool the polar and sub-polar regions, while perhaps under-cooling equatorial areas. The result would be an uneven, artificial climate system with consequences no climate model can reliably predict.
https://wattsupwiththat.com/2025/09/26/quit-promoting-mad-schemes-new-york-times-blocking-the-sun-is-a-dangerous-climate-gamble/