In Antarctica around 1% of the continent (4,000 km or 2,500 mi) is permanently ice-free – such areas are called dry valleys or Antarctic oasis. They are thought to be the world’s harshest deserts and it is estimated that these areas haven’t seen rain or snow in almost 2 million years. According to one study led by Australian scientists, due to climate change ice-free areas in Antarctica could expand up to 25% by the end of 21st century. This could drastically change the biodiversity of the continent.