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Deltares, spring 2020 21 Greenland's ice mass is melting at increasing rate. In addition to increasing ocean temperatures, this is also a major factor in global sea level rise. But the impact is not distributed evenly throughout the world because of the gravitational effect. As the Greenland ice mass gets smaller, gravity pull on seawater is reduced, and so the sea level descends near that ice mass. About 30 per cent of the world average sea level rise caused by Greenland's mass loss is seen on the North Sea coast. Landscapes formed by icebergs and ice sheets always look serene in photographs and documentaries. But the reality is more turbulent. Wind and weather lead to large-scale flows of ice masses during the year. Wind currents push ice from the North Pole through the strait between Greenland and Spitsbergen to the south, where it melts faster and faster. This WarmGulf Stream has several climate effects. It partly explains the relativelymild climate of North Sea countries. For example in theNether­ lands, the heat gradually released from the water to the air implies a relative warming of 1 to 1.5 degrees than without this Gulfstream. Global warming will change the distribution of heat across the continents. For more information: bart.vandenhurk@deltares.nl As the Greenland ice mass melts faster, more and more fresh water ends up in the oceans, with several implicati- ons. Cooled seawater flows northwards from the equator in the Gulf Stream, transporting large amounts of heat. A lot of water evapo- rates during that jour- ney, increasing the salt concentration in the seawater. This 'heavy' water sinks to the depths near Greenland and flows back towards the equator. But the increase in the amount of fresh, and therefore relatively light, melt water from Greenland disrupts this process. The result is a possible slowing down of the WarmGulf Stream and a reduction in heat transport to the North. 5 6 7 8