Droughts to become more frequent, severe: researchers

ABC News Online, Posted Mon Nov 17, 2008 5:02pm AEDT 

Updated Mon Nov 17, 2008 5:14pm AEDT

http://www.abc.net.au/news/stories/2008/11/17/2422031.htm

Canberra scientists say they have proven that the world's climate is changing faster than ever before.

The international research team drilled core samples from living corals off the Indonesian coast and found an increased frequency in the weather phenomenon known as the "Indian Ocean Dipole".

Like the El Nino weather effect, the Indian Ocean Dipole has a dramatic impact on the Australian climate, and can cause severe droughts.

Australian National University researcher Dr Mike Gagan says his coral samples show the dipole is occurring more regularly and that is changing Australian weather patterns.

"There's going to be not only more propensity for drought, there's going to be more variability," he said.

"If you get a dipole event superimposed onto an El Nino event, what may be a moderate El Nino event turns out to be a very strong drought."

Dr Gagan says the Dipole used to occur every 20 years, but is now happening about every four years.

He says Australia is in for more severe droughts in coming years.

"Now that we have a 160-year record we can see a clear trend towards more frequent dipole events," he said.

"When you look at what the climate models are telling us should happen as you warm the planet, a stronger Indian Ocean Dipole is something that climate models predict."