PLEA Network

9 January 2016, Climate News  Network, Ice melt speeds up sea level rise. Scientists have found evidence suggesting that melting icecap water from the interior of Greenland is adding to sea level rise faster than previously realised. Water may be flowing from the Greenland icecapand into the sea more quickly than anybody expected. It doesn’t mean that global warming has got conspicuously worse: rather, researchers have had to revise their understanding of the intricate physiology of the northern hemisphere’s biggest icecap. There is enough ice and snow packed deep over 1.7 million square kilometres of Greenland that, were it all to melt, would cause a rise in global sea levels of about six metres. Climate calculations  Since the icecap is melting as the atmospheric levels of the greenhouse gas carbon dioxide rise, and global temperatures rise with them, as a consequence of the human combustion of fossil fuels, the rate at which summer meltwater gets into the oceans becomes vital to climate calculations. The latest rethink begins not with the pools of water that collect on the surface each summer, or the acceleration of the glaciers as they make their way to the ocean, but with a granular layer of snow just below the surface, called firn. This is old snow in the process of being compacted into glacier ice, and covers the island in a layer up to 80 metres thick. Until now, researchers have understood this firn layer as a kind of sponge that absorbs meltwater and holds it, thus limiting the flow of melting ice into the sea. Read More here