Glaciers skating away, fast! by Matt Taylor
This week glaciologists in the USA have discovered that the Kangerdlugssuaq Glacier, situated to the southeast of Greenland is melting at a faster rate than ever before. This has sparked fears of much faster rising sea levels than previously thought.
The shocking discovery came after recent measurements of the glacier were compared to readings taken by a NASA plane back in 2002. During the 20th century the Kangerdlugssuaq glacier remained in a stable position, however the glaciologists have stated that the glacier could now be moving at an astonishing speed of 38 metres a day towards the sea. The reason why the glacier is tending to move much quicker is down to the fact that as the air continues to warm, so the ice begins to melt and act as a lubricant. Imagine an ice cube on a table, if you were to put it straight on there and try to blow it along, you would most probably not move it very far, but give it a few minutes to start melting and there will be a sufficient amount of water under it now for you to move it with ease. This is what is happening to the glacier as more and more melt water gets under it, the ice mass begins to almost buoy itself on the water.
Glaciers act in the same way that a river does with a source and a mouth. The source is high in the mountains or at a higher latitude, where snow falls to contribute to the source of the glacier and to feed it, allowing for advancement. This is rather like a conveyor belt, where snow falls at the top of the mountain, this additional weight pushes the ice sheet further down, and then ends in the sea, where parts will break off to become icebergs. With this sheet moving faster, there needs to be more and more snowfall to continue feeding it or else the glacier will completely disappear into the sea.
Last year it was also noted that Greenland’s largest ice sheet, the Jakobshavn Isbrae, had also switched into fast thaw and a similar trend is being seen in Antarctica, where at least 6 glaciers have been identified with accelerated melting. This could lead to the feared rises in sea levels. U.S scientists revealed that sea levels have risen 2.5cm (more than an inch) since 1995. If it continues at the same rate, sea level rises of at least 30 to 40cm’s would be a fair estimate over the coming century, which would affect coastal areas and hundreds of small islands.
There are also fears that the increase in freshwater, from the melting glacial caps could potentially weaken or cut-off some currents, which travel round the worlds oceans to export warm and cold water around the planet. This could dramatically change the face of weather around the world, with potentially devastating consequences. Our own example, here in the UK, is, if our Gulf Stream was to be cut off then we may begin to experience a very different climate?
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