Australian Climate
Australia has a wide range of tropical and mid latitude climates, though it lacks the high mountain ranges that diversify the weather and climate patterns on other continents. It is generally quite hot and dry. Australia receives less precipitation than any other continent except Antarctica—an annual average of only 16.5 inches (42 centimeters), with half of the continent receiving less than 12 inches (30 centimeters) per year. High pressure cells move from west to east across the continent, bringing clear skies and almost no rain. Much of western and west-central Australia is classified as subtropical desert, receiving limited, erratic rainfall.
Australia’s worst droughts—including those of 1982–83, 1991–95, and 2002–03—are generally attributed to a climate phenomenon called El Niño. El Niño usually occurs two or three times every decade. It is accompanied by a shift in water temperatures in the Pacific Ocean. As a result, rainfall due in eastern Australia fails to arrive, leaving the area parched. Contrasting with El Niño is the La Niña effect, which periodically brings flooding even to normally dry parts of Australia. Climate does change. About 30,000 years ago, the continent was much wetter and greener, providing grazing land and forests for giant mammals and other animals. But between 22,000 and 18,000 years ago, the climate was drier and colder. Glaciers covered parts of the highlands, yet the desert core was enlarged. Sand dunes covered parts of Victoria and Tasmania. The last Ice Age ended only 10,000 years ago. |