LIFTING THE LID ON ANTARCTICA

What was the coldest continent like without ice?

- SCOTT DUTFIELD

Antarctica hasn't always been a cold desert. For around 100 million years the southernmost continent was covered by lush rainforests and roamed by dinosaurs. Like all of the continents, the landmass of Antarctica sits on one of the seven major plates of Earth's crust. The heat generated by the core of our planet causes these plates to slowly move around the globe at a rate of around 1.5 centimetres per year. Throughout over 4-billion-years of Earth's history, the continents have found themselves in different orientations. Around 200 million years ago Antarctica was a long way from the South Pole and sat near the equator, shoulder to shoulder with Africa, South America and Australia. These continents formed a giant landmass known as Gondwanaland. Without a shard of ice in sight, Antarctica was a warm, rainforest-laden continent that looked more like modern-day New Zealand.

By around 90 to 83 million years ago, Antarctica reached its current location at the South Pole. At a time when Earth was experiencing its warmest climate in history, the surface temperature of Antarctica was around 12 degrees Celsius. This allowed swampy forests to persist on the continent, especially in West Antarctica, around 560 miles from the South Pole. As well as lush foliage, coldblooded reptiles such as ankylosaurus and mosasaurs called Antarctica home until around 34 million years ago, when the continent was encased in a sheet of ice. Swapping the forests for glaciers and dinosaurs for prehistoric penguins, it took just over 200,000 years for Antarctica to freeze as global temperatures fell by up to four degrees Celsius. Sea levels also fell by 40 metres as water was frozen into the sheet that covers the South Pole today.