How Big Is Antarctica? Size Comparison & Seasonal Changes

The short answer: very big—even bigger at certain times of the year—but bizzarely not quite as large as a lot of people imagine given the White Continent’s portrayal on many world maps. We’ll get to that, and more, in this breakdown of Antarctica’s size!

Area of Antarctica

Antarctica is the fifth-largest of the world’s continents, covering some 5.5 million square miles (14.2 million square kilometers) in area. That extent includes Antarctica’s islands and its fringing ice shelves, which are the floating coastal extensions of interior glaciers that front about 75 percent of the White Continent’s seacoast and account for roughly 11 percent of Antarctica’s area.

Whilst the figure above is generally considered to be the true size of Antarctica, it’s worth bearing in mind that a large proportion of Antarctica’s ice shelves are receding. It goes without saying that any changes to the outline of Antarctic pack ice and the White Continent’s ice-shelf margin will affect the size of Antarctica.

If you exclude ice shelves and islands and just take the outer margin of the White Continent to be the so-called “grounding line” where shelf ice meets bedrock, Antarctica covers about 4.8 million square miles (12.3 million square kilometers).

The “Pulsating Continent”

The slight difference in Antarctica’s outline between using the outer ice-shelf margin versus the grounding line described above pales in comparison to the fantastic fluctuation seen in its frozen area when you take into account its sea-ice periphery.

The aforementioned ice shelves of Antarctica are primarily freshwater features created by the seaward advance of glaciers draining the continent’s great ice sheets. In contrast, Antarctic sea ice is formed by the freezing of seawater, and undergoes a striking annual expansion and retraction that creates a highly variable “second coastline” of Antarctica.

At the seasonal minimum of Antarctic sea ice, observed in the late austral summer around February, it covers between two and three million square kilometers (roughly 772,000 and 1.2 million square miles). But by the end of the austral winter in September, the sea ice around Antarctica has typically expanded to about 7 million square miles (19 million square kilometers). That’s larger than the White Continent itself!

This effectively means that when taking into account sea ice, Antarctica approximately doubles in size each winter. No surprise then that White Content has also been dubbed the “pulsating continent” due to this dramatic seasonal change in areal extent.

Why is Antarctica So Big on Maps? Map Distortions & the Real Size of Antarctica

Look at a standard world map, print or online, and you’ll marvel at the apparent enormousness of Antarctica, forming a gigantic white blankness across the bottom of the chart.

Why does Antarctica look so big on a map? As we’ve established, Antarctica is indeed plenty large, but not that large.

The widespread Mercator map projection, schemed up in the mid-16th century by the Flemish mapmaker and geographer Gerardus Mercator, straightens out the meridians (the imaginary north-south lines intersecting both poles) and the parallels (the east-west-running lines of constant latitude perpendicular to the meridians). A consequence of this projection, innovated to improve navigation, is the inflation in size of features away from the equator, which reaches an extreme toward the Earth’s poles. Hence the big-time distortion of Antarctica—and of Greenland, which similarly looks genuinely humongous in its far northerly position.

Maps of a different projection that more accurately depict the relative sizes of continents aren’t hard to come by—and are definitely worth taking a gander at, as they lend a whole new sense of perspective when it comes to the dimensions of the White Continent.

Some Antarctica Size Comparisons

How does Antarctica stack up, size-wise, against other sizeable continents and landmasses? You could fit 50 or so United Kingdoms within the White Continent, which is roughly twice the size of Australia, just less than 1.5 times the size of the U.S., and about the same size as the conterminous United States and Mexico combined. (A little piece of trivia: If you draped the combined extent of the Antarctic Ice Sheet across the U.S. and Mexico, the ice would be about 7,000 feet—more than 2,000 meters—deep.)

Is Antarctica bigger than Europe? Yes, by a significant measure: That subcontinent covers about 3.9 million square miles (10.2 square kilometers) as opposed to Antarctica’s 5.5 million square miles (14.2 million square kilometers).

How big is Antarctica compared to North America? A bit more than half the size, as North America covers about 9.4 million square miles (24.3 million square kilometers).

How big is Antarctica compared to Africa? Just less than half the area of that continent, which covers about 11.6 million square miles (30.4 million square kilometers). Famously Antarctica is the largest desert on earth, and is approximately 1.5 times the size of the Sahara Desert which covers 3.6 million square miles (9.2 million square kilometers).

How about Asia? Antarctica is about 30 percent the size of that 17.2-million-square-mile (44.58-million-square-kilometer) continent. Let’s zoom in to Eurasia: Which is bigger, Russia or Antarctica? If you guessed the former—which is the biggest country by area in the world—you got it right: Russia sprawls over some 6.6 million square miles (about 17.1 million square kilometers). Amazingly the size of Antarctica (excluding ice shelves and islands) is almost exactly the same size as China and India combined.

How about the only other ice-sheet realm on Earth: Greenland, also (as we’ve mentioned) grossly distorted in size in a Mercator projection map? Antarctica’s much larger, Greenland being “only” 836,330 square miles (2.17 million square kilometers) in area. The Greenland Ice Sheet, meanwhile, covers about 660,000 square miles (1.71 million square kilometers): impressive, sure, but far smaller than the conglomerate Antarctic Ice Sheet (encompassing the East Antarctic, West Antarctic, and Antarctic Peninsula ice sheets), about 5.4 million square miles (14 million square kilometers) in extent.

Bask in the Vastness of Antarctica

Now that your head’s swirling with numbers, let’s get back to the main take-home message: Antarctica’s a gloriously big place, and certainly the largest expanse of terrestrial wilderness left on our precious planet. Come experience the awesome scale of the White Continent and its associated isles and seas for yourself!