{"id":96950,"date":"2020-11-19T08:00:38","date_gmt":"2020-11-19T13:00:38","guid":{"rendered":"http:\/\/kendallharmon.net\/?p=96950"},"modified":"2020-11-19T16:18:45","modified_gmt":"2020-11-19T21:18:45","slug":"science-mag-seas-are-rising-faster-than-ever","status":"publish","type":"post","link":"https:\/\/kendallharmon.net\/?p=96950","title":{"rendered":"(Science Mag) Seas are rising faster than ever"},"content":{"rendered":"

Ask climate scientists how fast the world\u2019s oceans are creeping upward, and many will say 3.2 millimeters per year\u2014a figure enshrined<\/a> in the last Intergovernmental Panel on Climate Change report, from 2014. But the number, based on satellite measurements taken since the early 1990s, is a long-term average. In fact, the global rate varied so much over that period that it was hard to say whether it was holding steady or accelerating.<\/p>\n

It was accelerating, big time. Faster melting of Greenland\u2019s ice has pushed the rate to 4.8 millimeters per year, according to a 10-year average compiled for Science<\/em> by Benjamin Hamlington, an ocean scientist at NASA\u2019s Jet Propulsion Laboratory (JPL) and head of the agency\u2019s sea level change team. \u201cThe [Greenland] mass loss has clearly kicked into higher gear,\u201d agrees Felix Landerer, a JPL sea level scientist. With the help of new data, new models of vertical land motion, and\u2014this month\u2014a new radar satellite, oceanographers are sharpening their picture of how fast, and where, the seas are gobbling up the land.<\/p>\n

Hamlington and colleagues first reported signs<\/a> of the speedup in 2018 in the Proceedings of the National Academy of Sciences<\/em>. Since then, they and others have become more confident about the trends. In a 2019 study in Nature Climate Change<\/em>, a group led by S\u00f6nke Dangendorf, a physical oceanographer at Old Dominion University, used tide gauge readings that predate satellite records to show seas have risen 20 centimeters since 1900<\/a>. The team\u2019s data show that, after a period of global dam building in the 1950s that held back surface water and slowed sea level rise, it began to accelerate in the late 1960s\u2014not the late 1980s, as many climate scientists assumed, Dangendorf says. \u201cThat was surprising,\u201d because the main drivers of sea level rise\u2014the thermal expansion of ocean water from global warming, together with melting glaciers and ice sheets\u2014were thought to have kicked in later.<\/p>\n

Read it all<\/a>.<\/p>\n

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Seas are rising even faster than scientists previously believed. With the help of new data, new models, and\u2014this month\u2014a new radar satellite, oceanographers are sharpening their picture of just how fast. https:\/\/t.co\/YYPI2kLMKb<\/a><\/p>\n

— News from Science (@NewsfromScience) November 18, 2020<\/a><\/p><\/blockquote>\n