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The La Nina phenomenon responsible for the devastating Queensland floods is also affecting Western Australia and will continue to do so until at least middle of 2011, according to a leading researcher at the Oceans Institute at The University of Western Australia.

The source waters of the Leeuwin Current are already several degrees warmer than normal, said Professor Charitha Pattiaratchi.

"According to satellite data obtained from NASA, the ocean off the North-West of WA - that is, the start of the Leeuwin Current - is more than three degrees warmer compared to last year," Professor Pattiaratchi said.

"The water temperatures are higher than 31 degrees, which I have not seen before in more than 20 years of researching WA's coastal waters.  The current La Nina is one of the strongest ever recorded."

Professor Pattiaratchi is Winthrop Professor of Coastal Oceanography and Head of the School of Environmental Systems Engineering.

He is an internationally renowned researcher in the effects of climate change on coastal regions of Western Australia, particularly focusing on ocean currents, wind and wave climate, sea level variability, coastal flooding and beach stability.

The Leeuwin Current is a warm current that travels southward along the WA coast and into the Great Australian Bight. In La Nina years, it typically flows stronger bringing warmer water southwards.

La Nina is a global phenomenon and the floods experienced recently in Sri Lanka and Brazil, and the accompanying loss of lives, were also attributed to La Nina.

Professor Pattiaratchi said that based on previous La Nina events we know what the effects on WA will be, but it is not possible to predict their severity.

In previous La Nina years, the South-West of WA has experienced:

• Above average rainfall;
• A higher number of tropical cyclones;
• Higher mean sea levels during winter, leading to increased coastal erosion under storm events; and
• Increased settlement of rock lobster larvae (puerulus), which is expected to result in a higher rock lobster catch in 2015 (four years from now).

Media references

Winthrop Professor Charitha Pattiaratchi , Oceans Institute  (+61 8)  6488 3179
Janine MacDonald (UWA Public Affairs)  (+61 8)  6488 5563  /  (+61 4) 32 637 716