The Australian continent
Australia comprises a land area of about 7.692 million square kilometres.
Although this is just five per cent of the world's land mass (149.45 million square kilometres), Australia is the planet's sixth largest country after Russia, Canada, China, the United States of America and Brazil. It is also the only one of the largest six nations that is completely surrounded by water.
Australia's land mass is:
- almost as great as that of the United States of America
- about 50 per cent greater than Europe, and
- 32 times greater than the United Kingdom.
Australia is the smallest of the world's continents. It is also the lowest, the flattest and (apart from Antarctica) the driest.
The highest point on the Australian mainland is Mount Kosciuszko, New South Wales, at 2228 metres above sea level. The lowest point is the dry bed of Lake Eyre, South Australia, which is 15 metres below sea level.
The mainland and Tasmania are surrounded by many thousands of small islands and numerous larger ones. Nearly 40 per cent of the total coastline length comprises island coastlines. As an island nation, coastlines play an important role in defining national, state and territory boundaries.
Nearly 20 per cent of Australia's land mass is classified as desert. As well as having a low average annual rainfall, rainfall across Australia is also variable. The rainfall pattern is concentric around the extensive arid core of the continent, with rainfall intensity high in the tropics and some coastal areas.
Climatic zones range from tropical rainforests, deserts and cool temperature forests to snow covered mountains.
Within this climate, our plants and animals have evolved on a geographically isolated continent, through a time of a slowly drying climate, combined with continuing high variability. The uniqueness of much of Australia's flora and fauna is thus at least partly due to these features of our climate.