What is solar geo-engineering and how can it help stave off global warming?
— Jamie Renquist, Salem, OR

Solar geo-engineering is a term describing any of various techniques for reducing the amount of sunlight that reaches the Earth and its atmosphere. Researchers are exploring the feasibility of utilizing solar geo-engineering to reflect some of the sun’s heat back into space before it can reach the Earth and further contribute to the greenhouse effect that is causing our climate to warm. Some ways of doing this include pumping sulfur aerosols into the atmosphere, sending huge space mirrors or reflective balloons into Earth’s orbit, enhancing the reflectivity of clouds by spraying water into them, and even just painting everybody’s roofs white.

While solar geo-engineering can’t do anything about the carbon dioxide already in our atmosphere that will be causing more warming for decades to come or longer, it can help reduce …