Global effects of Japan’s earthquake

New York Times : Besides the much-reported aftermath in Japan, last Friday’s earthquake also caused global effects: It moved Japan’s coastline, tilted Earth’s axis slightly, and shortened the length of the day. Japan is “wider than it was before,” said Ross Stein, a geophysicist at the US Geological Survey. Global positioning stations closest to the epicenter jumped 4 meters closer to the US. The earthquake also shifted Earth’s figure axis—the axis that Earth’s mass is balanced around—by 16 cm where it intersects the surface of the planet. By shifting the planet’s mass closer to its center, the earthquake also caused Earth’s rotation to speed up, shortening the day by 1.8 microseconds. None of this is unusual, however. “The Earth is always wobbling, and the length of the day is always changing,” said Richard Gross, a scientist at NASA’s Jet Propulsion Laboratory.