If we installed an opaque screen in space in the vicinity of Earth blocking all sun rays, how long will it take to cool the planet back to pre-industrial times?
I know global warming is not just about temp, but how heat is unable to dissipate because of greenhouse gases. Yet, I suppose if you turn the incoming heat off, this must have an impact.
So, rephrasing: after suppressing all sunlight, how ground temperature on Earth would vary?
To state the obvious: of course such a screen would not be easy to make nor deploy in space, but this is not the point.