Well, I think Munroe is not thinking big enough here.
Of course, this might increase global warming in the long run because the impact crater can produce CO2 from both of the global firestorms devastating plant life and the destruction of carbonate rock in the earth mantle, but I think that this can be minimized by choosing a suitable impact location (which was not a concern for Chicxulub) and is partly offset by a decline in fossil fuel use due to indirect effects. Also, all of the tipping point factors in climate change would work to our advantage: larger polar caps reflect more light, more permafrost binds more CO2 and so on.
At the worst, climate engineering might require periodic impacts on a scale of one per decade, which seems sustainable.
I dunno man, Randall Munroe thinks that they would cause global warming.
Well, I think Munroe is not thinking big enough here.
Of course, this might increase global warming in the long run because the impact crater can produce CO2 from both of the global firestorms devastating plant life and the destruction of carbonate rock in the earth mantle, but I think that this can be minimized by choosing a suitable impact location (which was not a concern for Chicxulub) and is partly offset by a decline in fossil fuel use due to indirect effects. Also, all of the tipping point factors in climate change would work to our advantage: larger polar caps reflect more light, more permafrost binds more CO2 and so on.
At the worst, climate engineering might require periodic impacts on a scale of one per decade, which seems sustainable.