But although a warm sea is a necessary condition for a hurricane, it is not a sufficient one.

ECONOMIST: Eye on the storm | The

During the Jurassic period, 165 million years ago, the area was a warm shallow sea.

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For roughly the first half of the past fifty million years, the region lay beneath a warm, shallow sea.

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The average temperature is above 40C, the sea is like a warm bath, the golden sand burns your feet and the ubiquitous tarmac is starting to sizzle.

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They have since been pushed into the Sea of Japan by a branch of the warm Kuroshio current that is running much closer to land than usual, and have spread up Japan's west coast and even through the Tsugaru strait between Japan's main island, Honshu, and northern Hokkaido into the Pacific Ocean.

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Israel is particularly worried by Iran's eagerness to warm relations with Sudan and Eritrea, a strategic spot on the Red Sea that could threaten Israeli shipping.

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Yet that is just what is happening in Greenland, whose relatively warm and wet sheet is on course to melt completely, bringing the prospect of a sea-level rise of perhaps seven metres.

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Great white sharks are attracted to the warm ocean currents along Australia's southern coastline and are a constant concern for divers who work in the sea.

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It is opening up a resort city where temperatures reach 40C in summer, and will be as warm as 10-15C by the sea when the Olympics take place from February 7-23 next year -- with organizers already stockpiling snow due to sporadic falls, Black says.

CNN: February 8, 2013 -- Updated 1159 GMT (1959 HKT)