Some of Australia's leading weather experts say the forecast arrival of an El Nino in the next few months is no cause for weather panic just yet.
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Australia's leading science agency CSIRO polled its principal weather researchers to further explain the Bureau of Meteorology's upgraded El Nino prediction from "watch" to "alert", meaning the drying weather pattern is now more likely than not.
After three boom years for farm production across Australia, the sudden reversal from La Nina to El Nino has many people worried.
CSIRO senior research scientist Nandini Ramesh said it was still difficult to say with confidence whether the predicted El Nino would be a high-magnitude event.
"International forecasts suggest a moderate-strength El Nino event is the most likely outcome, followed by a high-strength El Nino event,' Dr Ramesh said.
"The uncertainty about this comes from the atmosphere, which has had a relatively muted response thus far to the now well-established warm sea surface temperatures.
"How strong the El Nino event gets now depends on how the atmosphere evolves over the next few months."
CSIRO's ocean dynamics team leader Chris Chapman said it was not known exactly where and how the strongest sea surface temperatures (SSTs) will pop up until an El Nino event gets underway.
"However, given the currently high SSTs in the equatorial Pacific, an additional 'nudge' from El Nino could see record high SSTs in some regions," Dr Chapman said.
"The response of equatorial Pacific sea surface temperatures to El Nino depends on where you are and the 'flavour' of El Nino."
Responding to a question on whether climate change is making El Nino events worse, CSIRO climate intelligence director Jaci Brown said the atmosphere is warmer due to climate change and so hot, dry conditions associated with El Nino are exacerbated.
"Whether El Ninos are changed or made worse by climate change is a more complex question."
Dr Brown was also asked whether after three La Nina's in a row, Australia could not get three El Ninos in a row?
"A more pressing question is whether we are about to head into a multi-year drought which is associated with many factors, not just El Nino," Dr Brown said.
"At this stage our climate models cannot give us reliable forecast information beyond about six months. But we have seen multi-year droughts before and we will see them again."
Dr Ramesh said: "This is something we have not seen before; the longest El Ninos have been about two years long. La Nina and El Nino are not perfect mirror images of each other, and La Nina events often last longer than El Nino events do."
Drought Resiliance Mission lead Dr Graham Bonnett said El Nino events don't always lead to lower rainfall or droughts.
"We notice drought impacts more when relatively low rainfall years translate to poor crop and pasture growth, or prolonged dry years see water storage dams run low or empty.
"The timing of lower rainfall translating to poorer crop and pasture growth will depend on the amount of starting soil moisture."
Dr Bonnett was asked what Australia's primary producers could do to prepare for possible drier conditions?
"Livestock producers can monitor pasture growth and make stocking adjustments to match feed availability as the year unfolds.
"It's also important to monitor the amount of soil moisture relative to crop development. If it turns out to be a low rainfall year, crops can be conserved as hay or silage rather than going through to grain."
CSIRO hydrologist and group leader Dr Francis Chiew said it was also too early to predict how a potential El Nino may impact flows in the Murray-Darling Basin.
"The good news is wet conditions from three successive years La Nina years have filled our reservoirs and provided what is essentially a buffer for the system."
Regarding the increased bushfire risk from an El Nino, bushfire behaviour and risks leader Andrew Sullivan, said an El Nino did not necessarily mean the bushfire season would be a big one.
"However, the last few years have seen exceptional growing conditions for vegetation in most agricultural and bushland areas, particularly in south-eastern Australia," Dr Sullivan said.
"At the same time, wetter conditions have also made it more difficult for authorities to implement their planned hazard reduction burns in many locations."
Chief research scientist Pep Canadell said weather conditions conducive to bushfire in Australia have already increased over the past two decades, particularly in the southern and eastern parts of the country.
"Projections for the next decades under all future climate scenarios show that fire weather will continue to increase," Dr Canadell said.
Other climate experts have also weighed into the debate.
Ruby Leiber from the ARC Centre of Excellence for Climate Extremes at the University of Melbourne said there was still no guarantee an El Nino one will form.
"While the tropical Pacific Ocean has warmed to El Nino thresholds, the atmosphere is not responding in the way typical of an El Nino," she said.
"Every El Nino is different and so we cannot be certain as to what the weather and climate will do in response."
Chris McLennan
ACM national rural property writer based in Bacchus Marsh, Victoria. Career journalist. Multi award winner.
ACM national rural property writer based in Bacchus Marsh, Victoria. Career journalist. Multi award winner.
