(CNN) Extreme heat bowled over Europe last week, smashing records in its wake. Now, the heatwave that started in the Sahara has rolled into Greenland -- where more records are expected to crumble in the coming days.

That means the heatwave is now Greenland's problem, right? Not quite. When records fall in Greenland, it's everyone's problem.

Greenland is home to the world's second-largest ice sheet. And when it melts significantly -- as it is expected to do this year -- there are knock-on effects for sea levels and weather across the globe.

Photos: In pictures: Record-breaking heat wave in Europe People cool off next to the fountains at the Louvre Museum in Paris on Wednesday, July 24. Hide Caption 1 of 10 Photos: In pictures: Record-breaking heat wave in Europe A man cools down at an outdoor pool's shower in Baden-Wuerttemberg, Germany, on Thursday, July 25. Hide Caption 2 of 10 Photos: In pictures: Record-breaking heat wave in Europe A woman in Paris walks past a window reflecting a temperature of 41 degrees Celsius (105.8 degrees Fahrenheit) on Thursday, July 25. Hide Caption 3 of 10 Photos: In pictures: Record-breaking heat wave in Europe A dry part of the Loire's river bed is seen in Montjean-sur-Loire, France, on Wednesday, July 24. Hide Caption 4 of 10 Photos: In pictures: Record-breaking heat wave in Europe A boy cools off under a public water spray on the bank of the Seine river in Paris on Thursday, July 25. Hide Caption 5 of 10 Photos: In pictures: Record-breaking heat wave in Europe A woman shields herself with a newspaper in Milan, Italy, on Thursday, July 25. Hide Caption 6 of 10 Photos: In pictures: Record-breaking heat wave in Europe People cool off with a water fight at a park in The Hague, Netherlands, on Wednesday, July 24. Hide Caption 7 of 10 Photos: In pictures: Record-breaking heat wave in Europe A polar bear named Nanook cools off at a zoo in Gelsenkirchen, Germany, on Wednesday, July 24. Hide Caption 8 of 10 Photos: In pictures: Record-breaking heat wave in Europe People collect water from the public fountain in front of the Pantheon in Rome on Thursday, July 25. Hide Caption 9 of 10 Photos: In pictures: Record-breaking heat wave in Europe People cool off and sunbathe next to the Eiffel Tower in Paris on Thursday, July 25. Hide Caption 10 of 10

Greenland's ice sheet usually melts during the summer. This year, it started melting earlier, in May, and this week's heatwave is expected to accelerate the melt.

The country's mammoth ice sheet rises 3,000 meters above sea level. Forecasters predict that its summit will be particularly warm this week, at just below zero degrees.

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