地球"腰圍"變粗 都是全球變暖惹的禍

The Earth is putting on 'weight' around its 'midriff' - and global warming is to blame.

你相信嗎？地球的腰圍正在變得更粗，這全都是全球變暖惹的禍。

Melting ice in Antarctica and Greenland is adding volume to the oceans and this extra water is being pulled towards the Equator, adding to the girth at the widest part of our planet, according to scientists.

科學家們宣稱，全球氣候變暖使得南極和格林蘭島的冰川加速融化，並流入大洋，這部分“多出來”的水隨着地球自轉，都流向了赤道地區，從而使得地球的“腰圍”增加。

Earth had been 'slimming down' following the Ice Age, which finished about 20,000 years ago.

早在20000年前，地球正值冰河時期，那時的“腰圍”可以說是比較苗條。

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 at the middle.

在這一地質時期過程中，地球的表面以及大氣層的溫度都在降低，冰原冰川的重量如此之大，以至於迫使地殼和地幔發生了變形，使得兩者中部發生了隆起。

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.

事實上，氣球並非是一個完美的球體，北極地區要比赤道地區更加接近地心，兩地之間的這一差距大概是在數公里。

And it was believed that the rebound effect following the Ice Age would result in our planet becoming more of a perfect sphere.

　據信，由於在冰川時候之後的“反彈”的作用力，我們的地球正在向一個正規的球體逼近。

The 'bulge' at the Equator had been shrinking by less than a millimetre a year, according to National Geographic.

美國國家地理學會的數據顯示，赤道每年都在以不到一毫米的速度“萎縮”。

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

不過美國宇航局重力恢復與氣候試驗衛星的量測結果顯示，這種“反彈”的效果正在受到全球變暖的影響，瘦下去的“肚子”又長了回來。

'There's something else going on that offsets [the shrinking of the Earth's girth],' said John Wahr, a geophysicist at the University of Colorado.

美國科羅拉多州大學地球物理學家John Wahr說：“目前有一些因素抵消了這一趨近正球體的過程。”

The rate of melting ice at the North and South Poles - which totals 382 billion tons of ice a year - is counteracting the 'slimming' effect.

每年，北極和南極的冰川都在加速融化，並且達到了3820億噸，這些融水都使得地球的“腰圍”不減反增。