The melting of Greenland and Antarctica is changing the Earth's rotation [View all]

[TexasTowelie]

Sophisticated new gravity research suggests that changes in Earth's climate may actually be having a stunning geophysical effect: slightly moving the location of the planet's spin axis, or axis of daily rotation. In other words, even as the Earth spins on its axis in a west to east direction, completing a full rotation every 24 hours, that axis itself is also moving. This, in turn, means that the physical North and South poles are actually shifting, with the North Pole now drifting towards England.

And given that much of this is related to the loss of polar ice, a changing climate would appear to be at least partly - although perhaps not wholly - responsible. "If we lose mass from the Greenland ice sheet, we are essentially putting mass elsewhere. And as we redistribute the mass, the spin axis tends to find a new direction. And that's what we mean by polar motion," said Surendra Adhikari, a researcher with Caltech and NASA's Jet Propulsion Laboratory who conducted the work with his colleague Erik Ivins. The new research appeared Friday in Science Advances.

Ivins emphasizes that the study doesn't explicitly attribute the motion of the pole to human caused climate change - noting that "the word human is not in this paper." The study wasn't aimed at attribution of the causes of mass loss – it merely observed them using NASA's twin GRACE satellites, which measure gravitational changes at the Earth's surface, and tied that to polar motion.

At the same time, however, much research has suggested that the warming of the Earth is behind considerable polar ice mass, not only in Greenland and Antarctica, but also smaller glaciers around the world. NASA research, for instance, finds that Greenland is losing 287 billion tons of ice per year, while Antarctica is losing 134 billion tons.

Read more: http://www.sunherald.com/news/nation-world/national/article70882447.html