Critical Times

MORE severe droughts were inevitable if global warming continued, CSIRO climatologist Barrie Pittock warned today.

“While drought relief may well be appropriate in the short term, we have to treat the cause as well as the consequences,” Dr Pittock told a Victorian National Parks Association audience in Melbourne tonight.

“Increased temperature, due to emissions of greenhouse gases from fossil fuels and deforestation, is leading to increased evaporative losses from soil and vegetation, making droughts worse.”

Dr Pittock, of the CSIRO’s Climate Impact Group and author of Climate Change: Turning Up the Heat, said recent studies had shown that global warning was pushing the mid-latitude westerly winds towards the south and north poles.

“The low-pressure systems and cold fronts that bring rain to southern Australia are further south, so we only get the tail end of the fronts, with less rain than in earlier years,” Dr Pittock said.

Pittock said this trend was first seen in southwest western Australia, where rainfall started to drop in the 1970s.

He said such trends were having drastic effects on farming, biodiversity and urban populations.

“They will result in loss of biodiversity in rivers and streams, more severe wildfires, and dust storms,” Dr Pittock said.

Australia’s current drought was a symptom of climate change and its cause must be tackled.

“This means that serious attempts must be made to reduce greenhouse gas emissions,” he said.

“This has to happen this decade if more drastic impacts are to be avoided.”