Friday, December 2, 2016

Five feet of Sea Level Rise by 2050? Ten feet at New Orleans in that Case.

I have recently found out that because of the destabilisation of the Greenland and West Antarctic Ice Sheets in general, and the Pine Island Glacier in particular, we could see five feet of global mean sea-level rise by 2050.  Due to the gravity effects of the loss of ice at the poles, New Orleans will see twice as much seal level rise as the global mean.

Meltwater from the east end of the East Antarctica ice sheet.
As if Greenland and West Antarctica ice melt weren't bad enough.

This is six feet rise in sea level at New Orleans.
This is from a global mean of three feet.
Source: New Orleans Advocate 
From The Huffington Post, 18 November 2016, U.S. Climate Envoy Jonathan Pershing: Five Feet Of Sea Level Rise By 2050 Possible.
The mood in Marrakech was somber when top climate envoy for President Barack Obama Jonathan Pershing dropped a bombshell on observers gathered there: The rapid warming in polar regions the world is now witnessing may result in five feet—or 1.5 meters— of sea level rise by 2050. 
Pershing had met earlier with State Department Secretary John Kerry in Morocco at the 22nd UN Conference of the Parties to the UN Framework Convention on Climate Change, or COP22. Kerry had just returned from a trip to Antarctica. According to Pershing, Kerry told him that the Pine Island Glacier in Antarctica “is moving very fast and when it goes, we will see 1.5 meters of sea level rise by 2050.” 
“Five feet of sea level rise in less than 35 years — that is really soon,” said Pershing. “There are 65 million people now living in a state of conflict and 140 million who live less than 3 feet above sea level.
I had reported on the effects of gravity influences on the effect on sea level rise at New Orleans here, based on information reported in the New Orleans Advocate, which has come out with a new article November 23rd on local sea level rise this century: Study hands New Orleans bleak sea rise outlook, with some of highest projections in the world.
Just when you think the news about sea level rise couldn’t get much worse for New Orleans, it has. 
According to a study released this month, the city will experience one of the highest increases in sea level among 138 coastal cities around the planet because of its location on the northern Gulf of Mexico. 
New Orleans could see as much as 14.5 inches of sea level rise by 2040, and 6.5 feet by 2100 if the world doesn’t act quickly to lower greenhouse gas emissions, the main driver of global warming. 
The populated parts of the city, of course, are protected by levees rising to about 22 feet. The increase would be most evident outside the levees
Of course the study that predicts a 14.5 inches' rise by 2040 and 6.5 feet by 2100 does not take into account the above information about the increasingly rapid disintegration of the Greenland and Antarctica ice caps that Pershing dropped on the climate change conference in Marrakesh.

And the ice melt has started on East Antarctica as well, at its east end, reported by Robertscribbler on November xx: Did Föhn Winds Just Melt Two Miles of East Antarctic Surface Ice in One Day?
Supraglacial lake is just another word for a surface glacial melt lake. And these new lakes pose a big issue for ice sheet stability. Surface melt lakes are darker than white glacier surfaces. They act as lenses that focus sunlight. And the comparatively warm waters of these lakes can flood into the glacier itself — increasing the overall heat energy of the ice mass.

But water at the glacier surface doesn’t just sit there. It often bores down into the ice sheet — producing impacts for months and years after the surface lake’s formation. Sub surface lakes can form in the shadow of surface ponds. Transferring heat into the glacier year after year. In other cases, water from these lakes punches all the way to the glacier’s base. There the added lubrication of water speeds the glacier’s flow. All of these processes generate stresses and make glaciers less stable. And it is the presence of surface melt ponds that has been responsible for so much of Greenland’s speeding melt during recent years.
Now, a similar process is impacting the largest concentration of land ice on the planet. And while Greenland holds enough ice to raise sea levels by around 21 feet, East Antarctica contains enough to lift the world’s oceans by about 195 feet. Surface melt there, as a result, produces considerably more risk to the coastal cities of the world.
In other words, it looks like even Pershing's dire warning at Marrakesh recently is now outdated. Oh, crap.

For more info click here, here, here, herehere [scroll down to EXTINCTION (Yes, it is real)], and here