If Antarctica's ice sheets melted completely, global sea levels would rise by approximately 58 to 60 metres (190-197 ft), enough to submerge most coastal cities worldwide.

Antarctica's Ice Could Raise Seas by 60 Metres

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Antarctica isn't just a frozen wasteland at the bottom of the world. It's a colossal ice vault holding enough frozen water to reshape every coastline on Earth. If all that ice melted, sea levels would rise by approximately 58 to 60 metres—roughly the height of a 20-storey building.

To put that in perspective: goodbye London, New York, Tokyo, Sydney, Mumbai, and Shanghai. Gone. Submerged. Fish would swim through the streets of every major coastal city you've ever heard of.

The Numbers Are Staggering

Antarctica contains about 26.5 million cubic kilometres of ice. That's around 70% of all fresh water on Earth, frozen solid in a continent larger than Europe.

The ice sheet averages about 2,160 metres thick, but in some places it reaches over 4,700 metres deep. If you stacked the Empire State Building on top of itself ten times, you'd still be looking up at ice.

  • East Antarctic Ice Sheet: The big one. Contains enough ice to raise seas by 52 metres alone.
  • West Antarctic Ice Sheet: Smaller but less stable. Could add another 5-6 metres.
  • Antarctic Peninsula glaciers: The remaining metre or so.

Why "Everywhere" Matters

Here's what catches people off guard: the rise wouldn't be uniform, but it would be global. Water finds its level. Whether you're standing in Bangladesh or Boston, the ocean comes for you equally.

Some regions would actually see slightly more rise than others due to gravitational effects and land rebound, but we're splitting hairs when the baseline is a 60-metre catastrophe.

The Timeline Question

Before you start building an ark, know this: complete Antarctic melting would take thousands of years under even the most extreme warming scenarios. The ice sheets are simply too massive to disappear quickly.

But "quickly" is relative. Parts of West Antarctica are already melting faster than scientists predicted just a decade ago. The Thwaites Glacier—nicknamed the "Doomsday Glacier"—is losing about 50 billion tonnes of ice per year.

Current projections suggest sea levels could rise by about a metre by 2100 under high-emission scenarios. That's enough to threaten hundreds of millions of people without touching most of Antarctica's ice.

A World Transformed

In the full-melt scenario, Florida becomes an underwater memory. The Netherlands ceases to exist. Bangladesh loses most of its landmass, displacing over 100 million people. Denmark becomes an archipelago.

The new coastlines would run through what are currently suburbs and farmland. Entire nations would need to relocate. The economic and humanitarian consequences are essentially incalculable.

Antarctica's ice formed over 34 million years. It's been the planet's thermostat, its freshwater reserve, and its geographic anchor. The fact that we're now measuring how fast it's shrinking should give everyone pause.

Frequently Asked Questions

How much would sea levels rise if Antarctica melted?
If all of Antarctica's ice melted, global sea levels would rise by approximately 58 to 60 metres (190-197 feet), enough to submerge most coastal cities worldwide.
How long would it take for Antarctica to melt completely?
Complete melting of Antarctica would take thousands of years even under extreme warming scenarios. The ice sheets are too massive to disappear quickly, though parts are melting faster than previously predicted.
What cities would be underwater if Antarctica melted?
Nearly all major coastal cities would be submerged, including New York, London, Tokyo, Sydney, Shanghai, Mumbai, Miami, and hundreds of others. Any city below 60 metres elevation near a coast would be at risk.
How much ice is in Antarctica?
Antarctica contains approximately 26.5 million cubic kilometres of ice, representing about 70% of all fresh water on Earth. The ice averages 2,160 metres thick and exceeds 4,700 metres in some areas.
Is Antarctica actually melting right now?
Yes, parts of Antarctica are melting, particularly in West Antarctica. The Thwaites Glacier alone loses about 50 billion tonnes of ice annually. However, complete melting would still take millennia.

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