Transcript for Iceberg breaks away from Antarctic ice shelf

this evening, one of the largest icebergs ever recorded has now broken away from the antarctic ice shelf. Scientists have been concerned for some time about this, and announce's linsey Davis with the images coming in now. Reporter: A massive iceberg now free floating tonight after breaking away jrom the ice shelf in Antarctica. More than a trillion tons and the size of Delaware, the iceberg is one of the largest to ever snap off. The crack has been expanding for years. Scientists are calling the split an enormous geographical event and are studying what role, if any, regional warming may have played. Disappearing ice is an issue on both poles, as we saw firsthand during a visit to baffin island, just off the coast of Greenland in 2012. There's so much more water now compared to when I first came out here. And now it's, like, little islands of ice. While breaks have happened before, what is unusual about this latest break is the size, the concern is if enough large glaciers end up in the ocean, sea levels could rise, which is why scientists will be keeping close watch. ABC's news New York.

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