Ask Ethan: Can We Build A Sun Screen To Combat Global Climate Change?
“[W]hy don’t we evaluate building a “sun screen” in space to alter the amount of light (energy) earth receives? Everybody who did feel a total eclipse knows temperature goes down and light dims. So the idea is to build something that would stay between us and sun all year long…”
The Earth’s temperature is rising: that’s a fact. The overwhelming cause of this warming is human-caused emissions of greenhouse gases, like CO2 and methane. The CO2 concentration has now passed 410 parts per million, an increase of over 50% over pre-industrial revolution levels. If we cannot or will not reverse what’s driving the temperature change, we could instead try to counteract it. One proposal is to put a large device in space, between the Sun and the Earth, to block some of the incoming sunlight. As it turns out, blocking 2% would be enough to completely counteract the effects of human-caused global warming. Modifying our atmosphere is risky, but placing a sun screen in space to do the job has only one real drawback: its expense.