An oldNational Geographicinteractive gift passed around on Mondayshows what the continents would look favor if the seas rose 216 feet. That number is more than likely too low.

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For part reason, BuzzFeed top top Monday seized top top a National Geographic interactive from last month showing what the continents would look prefer if the seas rose 216 feet. The figure, attributed to the U. S. Geological Survey, doesn"t show up online. And, in reality — it"s probably too low.

Here"s just how the magazine describes the rationale for its evaluation of what a drowning civilization will watch like.
According come the U.S. Geology Survey, sea level on an iceless planet would it is in as much as 216 feet greater than the is today. It could take countless years and an ext than a thousand components per million to create such a world—but if we burn all the fossil fuels, we will obtain there.

That "thousands of years" caveat is crucial one; the maps imply what the civilization would look prefer if all of the glaciers and also ice hat on earth melted under warmer temperatures. That"s not going to take place in her lifetime. It might not take place in the joined States" lifetime.

The difficulty is that us can"t discover that "216 feet" figure everywhere — and the only numbers from the USGS to speak the sea level increase will be higher. In 2004, USA Today offered a figure of 215 feet, crediting the USGS, however that isn"t everywhere to it is in found, either.

The agency"s sea level rise details page puts the number at 80 meters — some 262 feet. It"s damaged down through melt location.

If all of Alaska"s glaciers melted, sea level would climb ~ 0.05 meter (about 0.16 feet). If every one of Earth"s temperate glaciers melted, sea level would climb ~ 0.3 meter (about one foot). If all of Greenland"s glaciers melted, sea level would climb ~ 6 meters (about 19.7 feet). If all of Antarctica"s glaciers melted, sea level would increase ~ 73 meter (about 240 feet).

That shows up to be based upon this 2000 study, which place the specific figure in ~ 80.32. One USGS report (that isn"t dated) place the figure greater still: "If all the existing glacial ice were to melt indigenous Antarctica and also Greenland, the seas would rise an additional 300 feet (90 meters) and also inundate many of the seaside cities of the world."

We"ve got to out to the USGS because that clarification. But it seems most likely that the base number is somewhat greater than the National Geographic projections.

More importantly, the raw figure of ice melt — including only the amount of water consisted of in the ice itself — vastly underestimates just how much sea levels will rise. The problem is that together fluids and also gasses get warmer, they rise in volume. Warmer water bring away up an ext physical an are than colder water, because the molecule have an ext energy. According to the UN"s Intergovernmental panel on Climate Change, i beg your pardon produces constant reports top top the effects of worldwide warming, the link in between warmer water and increased volume is substantial.

"On a multi-millennial time scale," its most recent breeze report reads, "the range from planet System Models of intermediary complexity says that thermal growth contributes between 0.20–0.63 m per °C of global mean temperature increase." In other words, for each degree that the temperature increases, the seas will rise between 0.2 and also 0.63 meters. The temperature climbs, the ice melts — and the seas expand.

Again, you"re no going to view this happen. What you"ll check out will be an ext subtle: wetter storms, hotter and also drier summers, much more flooding as we saw from Hurricane Sandy. However somewhere down the line, suspect our usage of fossil fuels isn"t checked, we could very well see s levels that are 216 feet greater than today. And also that may just be a method station before even higher increases to come.

Update, Tuesday: The USGS responded with its most current data.

Greenland: 7 meter West Antarctic ice sheet: 3.3 meters eastern Antarctic ice sheet: 52 meter All various other glaciers and tiny ice caps: 0.5 meters

That"s 62.8 meters, total — 206 feet in increase. But that doesn"t encompass the sea level expansion.

Update, Wednesday: Jason law from National Geographic wrote in.

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fter speaking v a variety of experts, we were resulted in Phillipe Huybrechts in ~ Vrije Universiteit Brussel, who most of those us spoke with taken into consideration an authority on the subject (including part at USGS). That quoted united state these numbers:

7.5 m indigenous Greenland 0.5 m from glaciers and ice cap 58 m from Antarctica (latest 2013 numbers) 66 m in total
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