Australia

Australia is the smallest continent. It is also the only country that is also a continent. It covers 7,682,300 sq km, or about 5 per cent of the earth's land area. Mainland Australia extends from 12°S to 38°S latitudes (12°S to 44"S if we include Tasmania) and 114° E to 154° E longitudes. Australia lies entirely in the Southern Hemisphere.

Australia can be divided into three major physical divisions-from west to east, the Western Plateau, the Central Lowlands, and the Eastern Highlands. The Western Plateau covers the western two-thirds of Australia. Most of the land is flat and covered with small shrubs, though at places isolated mountain ranges rise above the general level. A vast, dry, treeless plateau called the Nullarbor Plain extends along the southern edge of the Western Plateau.

The Central lowlands have the lowest elevations in Aus­tralia. Lake Eyre, the lowest point in Australia (16 metres ,below sea level), lies in the Central Lowlands. The Lowlands extend from the Gulf of Carpentaria in the north, across the continent to the southern shores. The region receives scanty rains, except in areas along the north and south coasts imd near the Eastern Highlands. The Eastern High­lands run almost parallel to the east coast of Australia, extending from Cape York Peninsula in the north to Tasmania in the south.

The region includes the highest elevations in Australia. Along the Pacific Coast lies a low plain bordered by sandy beaches and rocky cliffs. The Eastern Highlands are known as the Great Dividing Range because their slopes divide the flow of the rivers in the region. Those flowing down the eastern slopes drain into the ocean. Those rurming down the western slopes flow to the Central Lowlands. The Eastern Highlands are broad and low in the north and narrow and high in the south.

Australia's highest mountains rise in the Australian Alps in the extreme southern part of Eastern Highlands. Mount Kosciusky (2,228 m), in the Snowy Range of. the Alps, is the highest peak in Australia. The highlands drop steeply in the east towards the Pacific Ocean and more gently in the west towards the Central Lowlands. The Highlands are not a single range; they consist mainly of high plateaus that are broken in many places by gorges, hills, and low mountain ranges.

Most of the rivers of Australia go dry in some parts of the year and fill with water only during the rainy season. River Murray, originating from the Snowy Mountains in the Alps and flowing westward, is the continent's longest permanently flowing river. During the dry season in southern Australia, the Murray is fed by River Darling, Austalia's longest river. River Darling begins in the central part of the Eastern Highlands and flows southwestwards.
Deserts cover about a third of Australia. The four major deserts are the Simpson (western edge of the Central Lowlands), the Gibson, the Great Sandy and Great Victoria (central part of the Western Plateau) Off the north-east coast of Australia exists the Great Barrier Reef-the world's largest coral reef, extending more than 1900 km in length.

Australia lies south of the equator and so its seasons are opposite those in the Northern Hemisphere. Northern Australia lies in the tropics and so experiences warm season throughout the year. The wet season lasts from November through April and the dry season lasts from May through October. Southern Australia has four seasons-winter (June through August) is the coolest and wettest season and summer (December through February) is the hottest and driest season.