London, July 8 (IANS) Melting ice in Antarctica and Greenland is swelling the volume of oceans, with the excess water gravitating towards the equator, fattening the planet in its widest part.


The Earth had been 'slimming down' following the Ice Age, which finished about 20,000 years ago. During this geological period of long-term reduction in the temperature of the Earth's surface and atmosphere, the weight of ice sheets was so great that they deformed the Earth's crust and mantle, causing it to bulge in the middle.

The Earth isn't completely spherical - land at the North Pole is a number of kilometres nearer to the core of the planet than land at the Equator, the Daily Mail reports.

And it was believed that the rebound effect following Ice Age would result in our planet becoming more of a perfect sphere. The 'bulge' at the Equator had been shrinking by less than a millimetre a year, according to National Geographic.

But by looking at measurements from the Gravity Recovery and Climate Experiment (GRACE) satellites, it was found that this effect was reversing.

"There's something else going on that offsets (the shrinking of the Earth's girth)," said John Wahr, geophysicist at the University of Colorado.
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The rate of melting ice at the North and South Poles, which totals 382 billion tonnes of ice a year, is counteracting the 'slimming' effect.