CLIMATE : -A DIFFERENT- CRISES : AUSTRALIA

''There is a very strong link between global warming and the intensification in rainfall,'' said Andy Pitman, director of the ARC Center of Excellence for Climate Extremes at the University of New South Wales.

''There's good evidence to say extreme rain is becoming more extreme, due to global warming.

Kelly Miller stood in her doorway, watching the water rise to within a few inches of the century-old home where she runs an alternative medicine business.

Just recently, two huge forms have converged over eastern Australia, dumping more than three feet of rain in just five days. In a country that sustained the worst wildfires in its recorded history just a year ago, the deluge has become another record-breaker - a once-in-50-years event, or possibly 100, depending on the rain that was expected to to continue through.

Nearly 20,000 Australians have been forced to evacuate, and more than 150 schools have been closed.

Shane Fitzsimmons, the resilience commissioner for the state of New South Wales - a new position formed after after last year's fires - described the event as another compounding disaster.

Last year, huge fires combined into history-making infernos that scorched an area larger than many European countries. This year, thunderstorms have fused and hovered, delivering enough water to push rivers like the Hawkesbury to their highest levels since the 1960s.

Scientists note that both forms of catastrophe represent Australia's new normal. The country is one of many seeing a pattern of intensification : more extreme hot days and heat waves, as well as more extreme rainfalls over short periods.

It's tied to a warming earth, caused by greenhouse gases. Because global temperatures have risen 1.1 degrees Celsius, or about 2 degrees Fahrenheit, over preindustrial levels, landscapes dry out more quickly, producing severe droughts, even as more water vaporises into the atmosphere, increasing the likelihood of extreme downpours.

The World Students Society thanks author Damien Cave.