Melting Antarctic ice could cause gravity shift

The Independent (UK): The melting of one of the world's largest ice sheets would alter the Earth's field of gravity and even its rotation in space so much that it would cause sea levels along some coasts to rise faster than the global average, scientists said yesterday.

The rise in sea levels would be highest on the west and east coasts of North America where increases of 25 per cent more than the global average would cause catastrophic flooding in cities such as New York, Washington DC and San Francisco.

A study into how the West Antarctic Ice Sheet could respond to global warming has found its disintegration would change the focus of the planet's gravitational field, so sea levels would rise disproportionately more around North America than in other parts of the world. If the ice sheet covering West Antarctica disappears, the loss of so much mass from the southern hemisphere would effectively make the pull of gravity stronger in the northern hemisphere, affecting the spin of the Earth and causing sea levels to rise higher here than in the south, where the mass of ice is currently located.

However, the scientists also estimated that the global average sea level would not rise as much as previously expected due to the ice sheet melting into the oceans. This is because parts of the ice sheet are more stable than previously thought, and so would probably not slip into the sea even in a warmer world caused by man-made emissions of greenhouse gases, they found….

Antarctic sunsent, shot by Calee Allen, NOAA