Where would the energy go if a nuke intercepted a meteor?

Question

I thought of this question from watching the trailer for the new movie "Greenland" with Gerard Butler. Essentially in the trailer a huge comet falls towards the earth, apocalypse, etc.

However, that got me thinking: what if in such a situation (meteor strike), the World Governents sent a huge nuclear missle (or many missles) to intercept the meteor in the upper atmosphere? If the nuclear missles were powerful enough to completely incinerate/vaporize the meteor, what would happen to all the potential gravitational/kinetic energy contained in the falling meteor?

My intuition tells me that the meteor would become tiny particles and hence become harmless. However, if the meteor contained enough energy to cause an extinction event, wouldn't that energy have to be released somewhere, and cause a catastrophe anyway?

Answer 1

Your thinking is correct, the energy has to go somewhere. If you disperse the meteor into tons of small micrometeors that burn up in the atmosphere, that energy ends up heating the atmosphere. This would likely cause catastrophically-rapid, devastating climate effects that would be felt the world over - spontaneous forest fires, gigantic storms, incredibly high winds, and the like.

Meanwhile, the particles that were too small to burn up in the atmosphere create a giant cloud of dust (which is radioactive, by the way, thanks to the nuke) that is eventually dispersed across the planet. The dust lowers the amount of sunlight that hits the surface, reducing how well plants grow and wreaking an entirely different kind of havoc on the climate over the longer term. If the dust cloud is dense enough, crops fail and global surface temperatures drop to abnormally low levels until the dust clears.

On top of that, detonating a nuke in the upper atmosphere generates a large EMP, which could knock out many critical satellites and electrical networks, making a bad situation worse.