29 March 2016, The Guardian, Arctic sea ice extent breaks record low for winter. A record expanse of Arctic sea never froze over this winter and remained open water as a season of freakishly high temperatures produced deep – and likely irreversible – changes on the far north. Scientists at the National Snow and Ice Data Centre said on Monday that the sea ice cover attained an average maximum extent of 14.52m sq km (5.607m sq miles) on 24 March, the lowest winter maximum since records began in 1979. The low beats a record set only last year of 14.54m sq km (5.612m sq miles), reached on 25 February 2015. “I’ve never seen such a warm, crazy winter in the Arctic,” said NSIDC director Mark Serreze. “The heat was relentless.” It was the third straight month of record lows in the sea ice cover, after extreme temperatures in January and February stunned scientists. The winter months of utter darkness and extreme cold are typically the time of maximum growth in the ice cap, until it begins its seasonal decline in spring. With the ice cover down to 14.54m sq km, scientists now believe the Arctic is locked onto a course of continually shrinking sea ice – and that is before the 2016 melt season gets underway. Read More here
Tag Archives: oceans
28 March, Science Daily, Climate change: Greenland melting tied to shrinking Arctic sea ice. Vanishing Arctic sea ice. Dogged weather systems over Greenland. Far-flung surface ice melting on the massive island. These dramatic trends and global sea-level rise are linked, according to a study coauthored by Jennifer Francis, a research professor in Rutgers University’s Department of Marine and Coastal Sciences. During Greenland summers, melting Arctic sea ice favors stronger and more frequent “blocking-high” pressure systems, which spin clockwise, stay largely in place and can block cold, dry Canadian air from reaching the island. The highs tend to enhance the flow of warm, moist air over Greenland, contributing to increased extreme heat events and surface ice melting, according to the study. That, in turn, fuels sea-level rise, said Francis, who called rising seas a “monstrous” issue for coastal communities around the world. The increased melting on the Greenland ice sheet in recent years may also be linked to cooler-than-normal ocean temperatures south of the island, slowing ocean circulation. The study, published online in the Journal of Climate last month, tapped computer models and measurements in the field. “I think this study does a good job of pinning down the fact that the [Arctic sea] ice is disappearing for a whole bunch of reasons — and that is causing the surface of Greenland’s melt area to increase,” Francis said. The Greenland ice sheet holds an enormous volume of frozen water, and the global sea level would rise about 20 to 23 feet if it all melted, the study notes. Surface melting of the ice sheet has increased dramatically since the relative stability and modest snow accumulation in the 1970s, the study also notes. Read More here
28 March 2016, NASA, 2016 Arctic sea ice wintertime extent hits another record low. Arctic sea ice appears to have reached a record low wintertime maximum extent for the second year in a row, according to scientists at the NASA-supported National Snow and Ice Data Center (NSIDC) and NASA. Every year, the cap of frozen seawater floating on top of the Arctic Ocean and its neighboring seas melts during the spring and summer and grows back in the fall and winter months, reaching its maximum yearly extent between February and April. On March 24, Arctic sea ice extent peaked at 5.607 million square miles (14.52 million square kilometers), a new record low winter maximum extent in the satellite record that started in 1979. It is slightly smaller than the previous record low maximum extent of 5.612 million square miles (14.54 million square kilometers) that occurred last year. The 13 smallest maximum extents on the satellite record have happened in the last 13 years. The new record low follows record high temperatures in December, January and February around the globe and in the Arctic. The atmospheric warmth probably contributed to this lowest maximum extent, with air temperatures up to 10 degrees Fahrenheit above average at the edges of the ice pack where sea ice is thin, said Walt Meier, a sea ice scientist at NASA’s Goddard Space Flight Center in Greenbelt, Maryland. Read More here
19 March 2016, Climate News Network, Western Europe coasts face a pounding. Extreme weather caused by global warming could lead to more violent and more frequent storms devastating beaches on exposed Atlantic coastlines in Europe. The Atlantic seas could be getting rougher, with winter storms capable of causing dramatic changes to the beaches of Western Europe. And new research shows that the pounding delivered to the shorelines of the UK and France in the winter of 2013-2014 was the most violent since 1948. Gerd Masselink, professor of coastal geomorphology at Plymouth University School of Marine Science and Engineering, UK, and colleagues report in Geophysical Research Letters that they decided to switch focus from sea level rise resulting from global warming. Instead, they concentrated on the energy delivered by the rising waves as they crashed onto the beaches, dunes, shingle beds and rocky coasts, and on the consequent erosion of sediment. Rising levels For decades, climate scientists have predicted that rising levels of atmospheric greenhouse gases from the human combustion of fossil fuel could lead to global warming, and that warming would be accompanied by more frequent or more violent storms. That sea level rise inexorably means damage to coastlines has been repeatedly confirmed. And the fact that Atlantic waves have been getting higher was settled long ago. A study in 1991 revealed that wave heights − measured from a lightship and an ocean weather station − had been rising by 2% a year since 1950. ” “It should undoubtedly be considered in future coastal and sea defence planning along the Atlantic coast of Europe” The latest study examined open-coast sites across Scotland, Ireland, England, France, Portugal, Spain and Morocco. The researchers found that, along exposed coastlines in France and England, the beaches had taken a hammering. For every one metre strip of beach, there had been sand and shingle losses of up to 200 cubic metres. Read more here