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Greenland's Fastest Glacier Sets New Speed Record
vinces99 writes "The latest observations of Jakobshavn Glacier show that Greenland's largest glacier is moving ice from land into the ocean at a speed that appears to be the fastest ever recorded. Researchers from the University of Washington and the German Space Agency measured the speed of the glacier in 2012 and 2013. The results were published Feb. 3 in The Cryosphere, an open access journal of the European Geosciences Union. Jakobshavn Glacier, which is widely believed to be the glacier that produced the large iceberg that sank the Titanic in 1912, drains the Greenland ice sheet into a deep-ocean fjord on the west coast of the island. This speedup of Jakobshavn means that the glacier is adding more and more ice to the ocean, contributing to sea-level rise. 'We are now seeing summer speeds more than four times what they were in the 1990s, on a glacier which at that time was believed to be one of the fastest, if not the fastest, glacier in Greenland,' said lead author Ian Joughin, a glaciologist at the UW's Polar Science Center. The new observations show that in summer of 2012 the glacier reached a record speed of more than 10 miles (17 km) per year, or more than 150 feet (46 m) per day. These appear to be the fastest flow rates recorded for any glacier or ice stream in Greenland or Antarctica, researchers said."
Snowfall needs moist air. Warmer air holds more moisture. Increased snowfall is well in the scope of what's been thought to happen. There really doesn't need to be any alarmist campaign; simple scientific observation of the amplified greenhouse effect is enough.
It's not so simple as "10 cm/decade doesn't seem like much".
Imagine storm surges laid out on a bell curve, with height above mean high tide as the X axis. When you chose how close to build to the waterline, and the protections you put in, you probably wouldn't draw the line where you'd get one flood every thousand years. You might decide you can live with one flood every ten years. But shift the mean high tide by 20 cm over two decades, and that once a decade flood might happen eight or ten times a decade.
There's often a sharp line between a near miss and a disaster. A one foot rise over thirty years (roughly correponds to 1m/century) means that a seawall or levee that would have held back the flood get overtopped. A one foot rise means a place that never got flooded before could be in harms way. Some of the levees that failed in Katrina were overtopped by only a matter of inches. Others were overtopped by ten feet, but that's a different issue.
And in a lot of the world, the floodplain isn't chosen because it's a nice place to live. Bengladeshi subsistence farmers don't locate in low areas because of the beaches, but because that's the only land they can afford. These are people with very low levels of material consumption. They don't get much of the share of benefit from the carbon added to the atmosphere, but they bear a disproportionate share of the costs.
Post may contain irony: discontinue use if experiencing mood swings, nausea or elevated blood pressure.
Fourier's discovery that the Earth was warmer than it should be given its size and distance from the Sun was a major step forward in geoscience.. That he may not have had the mechanism right in no way detracts from the importance of that insight.