The European Union will reportedly look into blocking rays from the sun as a possible option to combat climate change.
Douglas MacMartin, associate professor at Cornell University, researches climate engineering (also known as solar geoengineering or climate intervention). He has published extensively on the subject, provided briefings to the UN Environment Program and testimony to the U.S. Congress.
MacMartin says:
"Reflecting a small amount of sunlight back to space (referred to as solar geoengineering or solar radiation modification) would cool the planet; the best understood approach to doing this would be to add aerosols such as sulfate into the stratosphere, high in the atmosphere.
"These ideas should only be considered as an additional component of our response to climate change, not as a substitute for cutting emissions. If your car is going to hit the car in front of you, you take your foot off the gas, you hit the brakes, and you still want seat-belts and air-bags; similarly for climate change we may need all the options and the conversation should never view this as a choice between options.
"We need more research to understand the details of what would happen if this were deployed. The reason to talk about this, research it, and take it seriously is that the climate modeling research to date suggests that it is quite likely that deployment would reduce many of the impacts of climate change, and thus reduce suffering – that is the single most important thing to know, but that point is often lost when talking only about the risks.
"The biggest challenges are likely to come not from the physical risks directly, but from the difficulty of making global decisions that are viewed as broadly legitimate; this is why it is so important that EU is emphasizing the development of international efforts both to assess the benefits and risks, as well as discussions surrounding governance."