Earth's inner heat keeps cities afloat. The rocks that the Earth is made of expand when it's warmer, like most materials; thus if the inside of the Earth were not as heat the Earth would be smaller.
Derrick Hasterok and David Chapman, of the University of Utah, say that the significance of this heating has been overlooked. In particular, it's stronger in some areas than in others -- the rock under the western U. S. is hotter than that under the eastern U. S., so the general fact that the West tends to be higher than the East is in part due to this phenomenon.
However, they claim that " would drop to 1,427 feet below the Atlantic ocean, and even deeper. would rest 3,756 feet below the surface of the Pacific ocean." This just doesn't feel right. Perhaps those places would fall to those heights below the current sea level -- I take this to mean they'd be slightly closer to the center of the Earth. But sea level would be redefined to be the new average height of the sea. The only way all these places could suddenly be under sea level is if there were more water.
In any case, it doesn't matter, because the heat is coming from radioactive decay of some very long-lived isotopes. Worry about global warming.
(Those of you who thought this blog was supposed to be about probability -- as the title might lead you to believe -- may be wondering why I'm making this post. But this blog is also about silly uses of mathematics in the media.)