If all of the ice in the world melted, sea levels would raise some 216 feet. But what exactly would that look like? And more specifically, what would such a worse-case scenario mean for the Earth’s population?

National Geographic has created a fascinating visual representation of this thought experiment and provided an analysis of how each continent would be affected by such a catastrophic change.

First off, this is not a blanket statement about climate change. As National Geographic notes, even scientists tracking the melting of ice around the world say it would take some 5,000 years for all the world’s ice to melt.

Still, it’s interesting to look at exactly what would happen if this scenario was taken to its most extreme conclusion.

As a result of the drastic rise in sea levels, the average temperature around the Earth would rise from 58 degrees to 80 degrees.

In North America, the entire Atlantic seaboard would vanish beneath the waves, including Florida and the Gulf Coast. Much of California would be underwater. Millions of Americans would be permanently dislocated from their homes to say nothing of the potentially insurmountable impact on natural wildlife.

And again, this scenario is only based on current population figures. Who knows what the Earth will look like in 5,000 years and how many people will be living here?

In South America, Buenos Aires, coastal Uruguay and most of Paraguay would be submerged.

Africa would technically be largely untouched but much of its would become inhabitable because of the increased temperature. In Egypt, Alexandria and Cairo would be “swamped” by flooding waters from the Mediterranean.

Many of Europe’s greatest landmarks would be destroyed: London would disappear, Venice, gone. The Netherlands and most of Denmark would also be entirely underwater.

In Asia, National Geographic says land currently inhabited by 600 million Chinese would be underwater, as would all of Bangladesh and coastal India.

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As for Australia, they would gain a new sea in the center of the continent, but lose the coastal strip where more than 80 percent of the population lives.

And Antarctica? Virtually unrecognizable. After all, that’s where the vast majority of the Earth’s ice resides today.

The Environmental Protection Agency says that overall ice reduction will depend on several factors, including: The rate at which levels of greenhouse gas concentrations in our atmosphere continue to increase, how strongly features of the climate (e.g., temperature, precipitation, and sea level) respond to the expected increase in greenhouse gas concentrations and natural influences on climate (e.g., from volcanic activity and changes in the sun's intensity) and natural processes within the climate system (e.g., changes in ocean circulation patterns)

(Photo credit: Jason Treat, Matthew Twombly, Web Barr, Maggie Smith, NGM Staff; Art: Kees Veenenbos. Sources: Philippe Huybrechts, Vrije Universiteit Brussel; Richard S. Williams Jr., Woods Hole Research Center; James C. Zachos, University of California Santa Cruz; USGS, NOAA, ETOPO1 Bedrock; 1 Arc-Minute Global Relief Model)