The sun over Greenland has risen two days early, baffling scientists and sparking fears that Arctic icecaps are melting faster than previously thought.

Experts say the sun should have risen over the Arctic nation's most westerly town, Ilulissat, yesterday, ending a month-and-a-half of winter darkness.

But for the first time in history light began creeping over the horizon at around 1pm on Tuesday - 48 hours ahead of the usual date of 13 January.