Asked by: Joe Elliott, Nottingham
If both ice sheets melted, the global sea level would rise by about 68m. This would put most of Europe underwater, along with large parts of Asia, Canada and South America. Greenland and Antarctica are currently both pushed downwards by the weight of the ice on top.
Once it melted, the land would eventually spring back, but this would take tens of thousands of years. In the meantime, Antarctica would resemble a mountainous archipelago like Australasia, and Greenland would be a central bowl below sea level, defended by a ring of mountains. With a warmer climate, there would definitely be some room for human settlement, but Antarctica is geologically very similar to the Andes so it’s never going to be prime real estate.
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