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Six-fold spike in polar ice loss lifts global oceans

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Greenland and Antarctica are shedding six times more ice than during the 1990s, driving sea level rise that could see annual flooding by 2100 in regions home today to some 400 million people, scientists have warned.

The kilometres-thick ice sheets atop land masses at the planet’s extremities sloughed off 6.4 trillion tonnes of mass from 1992 through 2017, adding nearly two centimetres (an inch) to the global watermark, according to an assessment by 89 researchers, the most comprehensive to date.

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Last summer’s Arctic heatwave will likely top the 2011 record for polar ice sheet loss of 552 billion tonnes, they reported in a pair of studies, published Wednesday in Nature.

That is roughly the equivalent of eight Olympic pools draining into the ocean every second.

While less visible than climate-enhanced hurricanes, sea level rise may ultimately prove the most devastating of global warming impacts.

Indeed, it is the added centimetres — perhaps added metres by the 22nd century — that make storm surges from climate-enhanced tropical cyclones so much more deadly and destructive, experts say.

“Every centimetre of sea level rise leads to coastal flooding and coastal erosion, disrupting lives around the planet,” said University of Leeds professor Andrew Shepherd, who led the analysis along with Erik Ivins from NASA’s Jet Propulsion Laboratory.

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“If Antarctica and Greenland continue to track worst-case climate warming scenarios, they will cause an extra 17 centimetres of sea level rise by the end of the century,” he said in a statement.

– ‘Irrefutable evidence’ –

That’s about a third of the rise forecast for 2100 by the UN’s climate science advisory panel (IPCC) under a scenario midway between a rapid drawdown of global greenhouse gases — seen by many as overly optimistic — and the unbridled expansion of fossil fuel use, also seen as unlikely.

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Melting glaciers and the expansion of ocean water as it warms accounted for most sea level rise through the 20th century, but ice sheet melt-off has become a major driver over the last decade.

Almost all of the ice lost from Antarctica, and half of that from Greenland, has been triggered by warming ocean water speeding the movement of glaciers toward the sea.

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Oceans help humanity by absorbing more than 90 percent of the excess heat from global warming.

The remainder of Greenland’s ice losses is due to rising air temperature, which creates roaring rivers of ocean-bound melt-water in summer.

The combined rate of mass loss from both ice sheets rose six-fold from 81 to 475 billion tonnes per year over less than three decades, the studies reported.

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The findings are grounded in decades of satellite data, in situ measurements, and computer modelling.

“Satellite measurements provide prima facie, irrefutable evidence,” said Ivins.

– Point of no return –

The IPCC forecasts about half-a-metre of sea level rise by 2100 under the middle-of-the-road emissions scenario known as RCP4.5.

If humanity defies the odds and achieves “carbon neutrality” by mid-century — which means any remaining emissions are somehow offset — sea level will likely be capped at 43 cm.

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The “worst case” pathway — which assumes carbon emissions continue unabated, or that Earth itself will begin to boost greenhouse gas concentrations — would see an 84 cm increase, according to an IPCC special report on oceans released in September.

Over the last decade, sea level has risen about four millimetres per year. But moving into the 22nd century, the waterline is likely to go up ten times faster, even under an optimistic emissions scenario.

Earth’s average surface temperature has warmed one degree Celsius over preindustrial levels, but polar regions have heated up twice as much.

Greenland and West Antarctica — which many scientists say has already passed a point-of-no-return and will shed all its ice eventually — together support enough frozen water to lift oceans about 13 metres.

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The rest of Antarctica, which is more stable, sits underneath more than 50 metres-worth of sea level rise.


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What will we tell future generations — and future Republican presidents — if Trump gets away with everything?

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If the nation manages to oust Donald Trump from the presidency in November — and he actually agrees to leave in January — the new administration and the Congress will have its hands full just trying to keep the country from falling even deeper into a depression and halting the death toll from the pandemic. Foreign policy will have to be dealt with immediately, as will the assessment of the damage to the administrative state. Our failed public health response to the coronavirus is a deadly wakeup call: The federal government has atrophied under the insane fiscal and political priorities inflicted upon it over the past couple of decades by nihilist Republicans and impotent Democrats. And that's just for starters.
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‘It’s a disgrace’: Conservative torches Trump and the GOP — saying they’ve betrayed voters

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In 2012, Stuart Stevens served as the chief strategist for Republican Mitt Romney’s presidential campaign and tried to prevent President Barack Obama from winning a second term; in 2020, he is a Never Trump conservative who is rooting for former Vice President Joe Biden, the presumptive Democratic presidential nominee. And when Stevens appeared on MSNBC’s “The 11th Hour” on Thursday night, August 6, he stressed to host Brian Williams that many GOP incumbents — from President Donald Trump to members of Congress — could be in trouble in November.

Promoting his new book, “It Was All a Lie: How the Republican Party Became Donald Trump,” Stevens told Williams, “This is a very negative environment for Republicans…. There are external forces out there that make this a very tough race for incumbents in the Republican Party.”

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Mask-hating Trump supporter banned from local store after she ‘rammed someone with a cart’: report

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A woman who was permanently banned from entering a local hardware store for refusing to wear a face mask tells Vox that she's proud that her defiance of public health standards got her kicked out.

In an interview, a Wyoming resident named Jacqueline says that her local Menards home and garden store has told her that she is no longer allowed to shop there for refusing to wear a face mask on two separate occasions.

Although she was still allowed to shop at the store after the first time she came in without a face mask, she was permanently given the boot when she got into a physical altercation with an employee during her second trip to the store.

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