Media release – Bureau of Meteorology, 19 September 2023
The Bureau declares El Niño and positive Indian Ocean Dipole events
The Bureau of Meteorology has declared that El Niño and a positive Indian Ocean Dipole (IOD) are underway.
Warmer and drier conditions will be more likely over spring and summer for parts of Australia, under the influence of these two climate drivers.
Bureau of Meteorology Climate Manager Dr Karl Braganza said both El Niño and a positive Indian Ocean Dipole tend to draw rain away from Australia.
“Over spring, their combined impact can increase the chance of below average rainfall over much of the continent and higher temperatures across the southern two-thirds of the country,” Dr Braganza said.
“The Bureau’s three-month forecast for Australian rainfall and temperature has been indicating warm and dry conditions for some time.”
“An established El Niño and positive IOD reinforces our confidence in those predictions. Based on history, it is now also more likely that warm and dry conditions will persist over eastern Australia until autumn.”
El Niño events increase the risk of extreme temperature shifts, like heatwaves and hotter days.
Increased fire danger in south-eastern Australia is associated with El Niño conditions. A positive IOD contributes to greater fire risk over southeast Australia in spring, while El Niño contributes to elevated fire risk over both spring and summer.
The Bureau made the El Niño declaration after three of the four El Niño criteria were met, including a sustained response in the atmospheric circulation above the tropical Pacific.
The last time Australia encountered both El Niño and a positive IOD was in 2015.
“Around two-thirds of Australia’s driest years on record were during El Niño however, no two El Niño or IOD events or their impacts are the same,” Dr Braganza said.
“El Niño is part of a natural climate cycle that affects global weather and occurs on average every three to five years.”
Bureau Senior Climatologist Catherine Ganter said the Indian Ocean Dipole can have as large an influence on Australia’s rainfall and temperature as El Niño.
“A positive IOD often results in below average rainfall during spring for much of central and southern Australia and warmer than average maximum temperatures for the southern two-thirds of Australia,” Ms Ganter said.
“Similar to El Niño, the IOD describes a natural climate cycle brought about by sustained changes in the difference between sea surface temperatures in the tropical western and eastern Indian Ocean.”
Since 1960, when reliable records began for the IOD, there have been around 16 positive IOD and 15 El Niño years. Seven years have seen positive IOD and El Niño events happen at the same time.
For more information:
Climate Driver Update: Climate Driver Update (bom.gov.au)
Long-range forecast: Overview—Summary – Climate Outlooks (bom.gov.au)
Media release – Farmers for Climate Action, 19 September 2023
Weather bureau confirms what farmers are already experiencing – it’s getting hot and dry
Farmers for Climate Action is calling for urgent action to limit climate change as it emerges farmers are officially facing an El Niño weather pattern after three years of La Niña.
The Bureau of Meteorology today declared Australia is officially in an El Niño weather pattern, meaning warmer drier conditions are more likely for south-eastern Australia, and this will be made more extreme by climate change.
Already some farmers, including Farmers for Climate Action member Peter Lake who farms near Grafton on the NSW North Coast, are officially in drought conditions after battling floods 12 months ago.
“It turned from mud to concrete in a couple of weeks and suddenly everything was just dry. From flood to drought, climate change is making the changes more extreme,” Mr Lake said.
Farmers for Climate Action Chair Brett Hall, who farms in the Derwent Valley in Tasmania, said many farmers were concerned about the possibility of warmer, drier conditions and increased weather variability for eastern Australia this spring and summer.
“Although some farmers have had reasonable conditions recently, we know things can change in a few months.”
Mr Hall said that Australian farmers are great at adapting, but that ultimately we need to address the driving cause of climate change – emissions.
“Farmers are always looking three steps ahead to the next event but there are limits to their adaptation. While we adapt and mitigate on-farm, we need to know the rest of the economy is doing its bit to reduce emissions and tackle climate change, which is causing more frequent and severe weather events.”
Farmers for Climate Action, an organisation representing 8000 farmers, hosted a webinar “El Niño explained” in July bringing together a range of speakers, including from the BoM and Birchip Cropping Group to help farmers prepare. That presentation is available here.
