Call that a drought? Well here’s the bad news

DROUGHT-hit eastern Australia is, surprisingly, coming out of a long, wet phase.

1983. Sheep kick up dust on a drought hit property in Werrimull, Victoria. Droughts - Australia - 1980-. Neg: 830609/116

DROUGHT-hit eastern Australia is, surprisingly, coming out of a long, wet phase.

The five decades from 1950 to 2000 were found to be among the wettest periods in the past 500 years.

Melbourne University associate professor Patrick Baker, and a research team from the University of NSW, have delved deeper than anyone before into our rain history.

They used the study of tree rings and even coral to look back 500 years into eastern Australia’s rain history.

The team studied 176 tree-ring chronologies from Australia, New Zealand and Indonesia as well as a coral rec­ord from Queensland to produce a drought atlas for eastern Australia and New Zealand.

“The fact that 1950-2000 was a wet period definitely doesn’t mean that droughts are becoming less frequent,” Prof Baker said.

“One of the important features that our reconstruction of hydroclimate across eastern Australia and New Zealand showed was that decades-long periods of drought and wet cycle back and forth.

“So, just because it has been wet recently doesn’t mean we can’t cycle into a drier phase.”

The concern now is that modern farming may have been based on more rain than historically usual.

Prof Baker said many of the infrastructure, planning and agricultural systems des­igned and developed from 1950 to 2000 were based on estimates of water availability that were relatively high in the context of the past 500 years. “If we cycle into a dry per­iod, those systems might be put under considerable stress,” he said.

Prof Baker said that in terms of intensity, the five worst drought years in the past 500 years all happened before 1900.

Prof Baker said he hoped they could develop climate models to “project what future conditions” may look like for the rest of the 21st century.

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