Top Scientists Warn of Catastrophic Sea Level Rise

Dr. James Hansen, who was the lead climate scientist at NASA, and sixteen other top scientists have concluded the Greenland and Antarctic glaciers will melt ten times faster than previous estimates, leading to sea level rise of ten or more feet in as little as 50 years.

In their newly released study: "Ice melt, sea level rise and superstorms: evidence from paleoclimate data, climate modeling, and modern observations that 2 ◦C global warming could be dangerous," the scientists warn that "Amplifying feedbacks in the Southern Ocean and atmosphere contribute to dramatic climate change in our simulations."
We conclude that continued high emissions will make multi-meter sea level rise practically unavoidable and likely to occur this century. Social disruption and economic consequences of such large sea level rise could be devastating. It is not difficult to imagine that conflicts arising from forced migrations and economic collapse might make the planet ungovernable, threatening the fabric of civilization.
They are describing an ocean feedback loop near Antarctica that results in cooler freshwater from melting glaciers forcing warmer, saltier water underneath the ice sheets, speeding up the melting rate.

This would put coastal cities at significant risk of flooding, with land and property disappearing underwater altogether in some locations, and with cold air outbreaks to middle latitudes:
In the North Atlantic Ocean the increase in sea level pressure in winter slows the westerlies. Thus instead of a strong zonal wind that keeps cold polar air locked in the Arctic, there is a tendency for a less zonal flow and thus more cold air outbreaks to middle latitudes.
They go on to warn that the previous target of 2 degrees centigrade cap for Climate Change is not safe, even as we are set to blow well past that.  The feedback loop, the ocean's role in regulating our climate, and its inability to keep up with changes, present a greater danger than previously anticipated, and that it cannot be easily or quickly restored:
Not only do we see evidence of changes beginning to happen in the climate system, as discussed above, but we have also associated these changes with amplifying feedback processes. We understand that in a system that is out of equilibrium, a system in which the equilibrium is difficult to restore rapidly, a system in which major components such as the ocean and ice sheets have great inertia but are beginning to change, the existence of such amplifying feedbacks presents a situation of great concern. There is a possibility, a real danger, that we will hand young people and future generations a climate system that is practically out of their control. 
The full study can be found at: http://www.atmos-chem-phys.net/16/3761/2016/acp-16-3761-2016.pdf


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