1. Antarctica holds most of the world’s fresh water
An incredible 60-90% of the world’s fresh water is locked in Antarctica’s vast ice sheet. The Antarctic ice sheet is the largest on Earth, covering an incredible 14 million km² (5.4 million square miles) of Antarctic mountain ranges, valleys and plateaus. This leaves only 1% of Antarctica permanently ice-free. Some areas are ice-free in the summer, including many of the areas we visit on the Antarctic Peninsula.
At its deepest, Antarctica’s ice is 4.5km (2.7 miles) thick – that’s half the height of Mt Everest! If it all melted, global sea levels would rise about 60 m (200 ft).
2. Antarctica is a desert
When most of us think of deserts we think of sand dunes and sizzling temperatures, but technically a desert doesn’t have to be hot or sandy, it’s more about how much precipitation the area receives as rain, snow, mist or fog. A desert is any region that receives very little annual precipitation.
The average annual rainfall at the South Pole over the past 30 years was just over 10 mm (0.4 in). Although there is more precipitation towards the coast, the average across the continent is low enough to classify Antarctica as a polar desert.
So while Antarctica may be covered in ice, it has taken an incredible 45 million years to grow to its current thickness, because so little rain falls there.
As well as being one of the driest continents on Earth, Antarctica is also the coldest, windiest and highest.
3. Antarctica used to be as warm as Melbourne
Given that the coldest ever land temperature was recorded in Antarctica of -89.2°C (-128.6°F), it can be hard to imagine Antarctica as a warm, temperate paradise. But Antarctica hasn’t always been an icy land locked in the grip of a massive ice sheet. In fact, Antarctica was once almost as warm as Melbourne is today.
Researchers have estimated that 40-50 million years ago, temperatures across Antarctica reached up to 17°C (62.6°F). Scientists have also found fossils showing that Antarctica was once covered with verdant green forests and inhabited by dinosaurs!
4. The Antarctic Peninsula is one of the most rapidly warming areas on Earth
The Antarctic Peninsula is warming more quickly than many other areas on Earth. In fact, it is one of the most rapidly warming areas on the planet. Over the past 50 years, average temperatures across the Antarctic Peninsula have increased by 3°C (37.4°F), five times the average increase on Earth.
This has led to some changes, for example where and when penguins form colonies and sea ice forms. It also means that the lush mosses of the Antarctic Peninsula have a slightly longer growing season.
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