|The U.S. divided by climate change|
That may not happen because civilization, the source of carbon dioxide and other green house gases, will be slowed down or broken down well before that (if the melt continues).
Today the International Arctic Monitoring and Assessement Program, AMAP, will begin a conference concerning, among other things, how wrong their past calculations have been.
They continually, substantially underestimate the melt of the polar ice sheets.
Consequently they have been underestimating the projected rise in ocean level around the globe which is happening as a result of the melt.
They are like other scientists in general who have continued time and time again to underestimate the impact of global warming in other areas affected by civilization's incessant pollution of the Earth.
Clearly, scientists are impacted by the pressure of denial as well as economic pressures from interest groups or governments that constantly urge them to fudge on the data, that is, to make "it" look better than "it" really is.
Upton Sinclair is said to have made a very lasting observation concerning the nature of humanity, including scientists:
"It is difficult to get a man to understand something when his salary depends upon his not understanding it".
Based upon underestimates of the acceleration of the factors causing the ocean levels to rise, the oceans may rise as much as 50 feet (23% of maximum) in some locations over the 21st Century (see update below).
However, the impacts of polar melt will be felt from now on as the climate degenerates into unhelpful patterns that will have an ever increasing impact on civilization.
The map above shows that the major ports would be destroyed ultimately, but will be damaged well before they become useless.
Even a 5 ft. rise in ocean level would amount to a worldwide catastrophe for civilization as we know it.
Hurricanes in the Gulf of Mexico, Atlantic, and Pacific oceans could easily have a 20ft surge, which would drive the oceans even further inland during storms.
The lunatic fringe (a.k.a. "the establishment") constantly talks about how much it will cost not to continue business as usual, missing the elephant in the room, which is that it will cost everything if they continue to decide not to change course.
According to one climate change study, the melting of Greenland's ice sheet would raise the oceans by twenty-three feet (23') (National Geographic).
If both poles were to melt the oceans would rise two-hundred-fifteen feet (215') (USA Today).
That turns out to match generalized calculations that Antarctica has about ten times more ice than the Arctic North Polar caps (See Vol. of Polar Caps, which standardizes the total volume of both caps at 33 million cubic kilometers of water. "For Antarctica, the approximate volume is 30,000,000 km3. For Greenland, it is approximately 3,000,000 km3").
NASA has perfected the estimates with radar from some of its satellites. Dredd Blog covered the impact of rising oceans in the post Nation Building - The Will of The Wind.
The first inhabited island has now gone under as a result of global warming induced ocean rise:
Rising seas, caused by global warming, have for the first time washed an inhabited island off the face of the Earth. The obliteration of Lohachara island, in India's part of the Sundarbans where the Ganges and the Brahmaputra rivers empty into the Bay of Bengal, marks the moment when one of the most apocalyptic predictions of environmentalists and climate scientists has started coming true.(Climaction, see also this). We can't call it apocalyptic predictions anymore, it should now be referred to as history and "history in the making".
A new core sample study within the Arctic Circle shows that the ice at the poles can melt rather starkly.