North America is toast. Anywhere coastal is toast. Inland Europe and Africa might survive?

It's worse than that. Yellowstone National Park has an area of 8,991 km² and the world's oceans have a volume of approximately 1.35 billion km³, so that translates into a column a little over 150,000 kilometers tall.

If we assume the column is starting out stationary relative to Earth's surface then most of the water is going to be flung away from Earth, probably being ultimately swept out of the inner solar system by light pressure from the Sun. If Yellowstone were at the equator then only the stuff below 25,000 kilometers would fall back to the ground (look up "space elevator safety" in Google, the water column is effectively a space elevator with no tensile strength to hold it together). Yellowstone's latitude is about 45°N, though, so we'll get to keep more. I'm not sure how to calculate it, maybe twice as much? So Earth winds up losing two thirds of its water in this scenario.

If the column is not stationary relative to Earth's surface and instead is stationary relative to Earth's center, we get to keep all the water - the column drops straight downward. Earth is rotating under it so the point of impact moves steadily westward. That's fortunate, it mostly pummels the Pacific basin. But I think it's not going to matter much because there's a tremendous amount of impact energy coming down. I'm not feeling up to doing all the integrals and whatnot to get an exact value, an approximate estimate should suffice. A quick Googling tells me something falling from geostationary orbit to the ground would hit at 10.3 km/s, and the Apollo capsules returning from the Moon hit at 11 km/s, so let's say 10.5 km/s on average for the falling water. The total mass of the oceans are 1.35×10^21 kg. That much mass moving at 10.5 km/s works out to 7.44×10^28 joules of energy. The asteroid impact that killed the dinosaurs is estimated to have delivered about 10^25 joules of energy, so when the ocean falls back to Earth it'll deliver approximately *ten thousand times* as much impact energy.

This is bad. Earth's atmosphere is going to be composed of superheated steam after this, it's unlikely that even well-prepared and deeply-buried nuclear bunkers will survive. It's probably the end of all macroscopic life on Earth.

Oh, speaking of the atmosphere, when the ocean teleported away we were left with huge basins covering 70% of Earth's surface that were suddenly filled with vacuum several kilometers deep. The atmosphere would collapse down into the ocean basins and produce very destructive shockwaves immediately. Most of Earth's major population centers are coastal, so I expect most people would already be dead before the effects of the falling ocean wiped out the survivors.