Essay by Eric Worrall
Cyclone Alfred, Australia’s big East Coast cyclone was until recently hyped as a symptom of the climate apocalypse. But doomsayers are facing another disappointment from nature.
Is climate change supercharging Tropical Cyclone Alfred as it powers towards Australia?
Cyclone Alfred formed in the Coral Sea towards the end of February when sea surface temperatures were almost 1C hotter than usual
Tropical Cyclone Alfred is due to hit south-east Queensland some time on Saturday morning, bringing the risk of destructive winds, extreme flooding and storm surges to millions of people around Brisbane, the Gold Coast and northern New South Wales.
After last year was recorded as the hottest on record around the world, and the hottest for Australia’s oceans, what role could the climate crisis be playing in Tropical Cyclone Alfred and its impacts?
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Fortunately Cyclone Alfred is turning into a fizzle. A powerful storm which will bring lots of rain and flooding, but no longer a catastrophic cyclone.
AS IT HAPPENED: Cyclone Alfred downgraded as it nears coast, expected to cross between Maroochydore and Brisbane; Albanese scraps plan for April election; ‘Dangerous times ahead’ as wind, rain hammer millions
By Adam Vidler Daniel Jeffrey Emily Bennett Yashee Sharma 12:30am Mar 8, 2025
Tropical Cyclone Alfred downgraded
By Karishma Sarkari07 Mar 2025 23:25
Cyclone Alfred has been downgraded to a category 1 storm in the latest advice issued by the Bureau of Meteorology.
The system is moving north-west at 9km/h, pushing back the timing it’s forecast to cross the coast.
Alfred is still on track to cross over the Moreton Bay Islands early on Saturday morning before crossing the mainland coast between Brisband and Maroochydore later in the day.
The cyclone is forecast to weaken as it moves inland late Saturday and Sunday.
While damaging wind gusts up to 120km/h and heavy to intense rainfall is still forecast, bringing the possibility of life-threatening flash flooding, the weather bureau says destructive wind gusts are no longer expected.
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Are Aussie cyclones becoming more frequent?
The following is a rather confused statement from the Australian CSIRO, Australia’s peak scientific body. Cyclone frequency is declining, but their broken theories suggests cyclone frequency should be rising.
3. Has the frequency of tropical cyclones changed?
Research has shown a statistically-significant downward trend in the annual number of tropical cyclones in the Australian region over the period extending from 1981/82 to 2017/18, during the period of satellite images. The reasons for this downward trend are still being determined but are likely to be due to a combination of both natural variability and longer-term climate change. Additional non-satellite observations suggest there has also been a longer-term reduction in the number of tropical cyclones since 1900.
The Bureau of Meteorology’s satellite record is relatively short and there have been changes in the historical methods of analysis. Combined with the high variability in tropical cyclone numbers and influences of natural variability such as the El Niño-Southern Oscillation, it makes it difficult to attribute trends to any single factor.
However, it is clear that sea surface temperatures off the northern Australian coast have increased – part of a significant warming of the oceans that has been observed in the past 50 years due to increases in greenhouse gases. Warmer oceans tend to increase the amount of moisture that gets transported from the ocean to the atmosphere, and a warmer atmosphere can hold more moisture and so there is a greater potential for intense rainfall events with tropical cyclones.
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Read more: https://www.csiro.au/en/news/All/Articles/2025/March/things-to-know-about-tropical-cyclones
Obviously the risk of damaging floods is still a serious concern, and the remnants of the cyclone may dump a lot of water into Brisbane’s rivers or other low laying areas. But there may be another explanation for why that flood risk in Brisbane is so severe.
From a few days ago;
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‘Anxiously watching’: Huge Cyclone call made
Even though South East Queensland’s dams are almost full, not a single litre of water will be released until Alfred’s predicted 600mm of rain starts to fall.
“We don’t always know when and where rain will fall,” a Seqwater spokesperson told The Courier-Mail.
“Our 24/7 Flood Operations Centre is mobilised and – pending rainfall – is prepared to make controlled, gated releases later this week if required.”
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Why are dam operators being ordered to cling on to every drop of water until the last possible moment? The reason of course, is not enough dam capacity. As Brisbane and other Queensland city populations have boomed, there has been little interest in providing water resources to match the growing population. The result is dam operators have to hang on to every drop of water, and only release that water when they are certain incoming storms will hit their catchment area – even when the incoming storm is a cyclone.
SEQ does not have enough drinking water for booming population
By Felicity Caldwell
August 19, 2021 — 8.00pmSouth-east Queensland will not have enough drinking water to support its rapidly growing population amid fears the region’s dams will struggle to supply millions of extra residents.
The revelation comes as residents could be forced to endure mandatory water restrictions in less than four months.
A stark warning about the need for new water sources – such as a dam or desalination plant – was emailed to Water Minister Glenn Butcher’s office in December, with a report revealing demand for water would increase as the south-east Queensland population grew by more than two million people over the next 25 years.
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If the dams had greater capacity, there would be much less risk of flooding – dam operators could confidently run their dams down in the face of rainfall threats, without fear of water shortages if the rain misses. The spare dam capacity could be used to soak up floodwater in the catchment area which feeds the dam.
The picture at the top of the article shows the potential consequences of failing to release dam water until the last minute.
In 2013 Brisbane was impacted by Cyclone Oswald, and suffered a severe rainfall and flooding event.
Then as now, dam operators were ordered to delay release until the last moment. The result was catastrophic – when 3ft+ of rain abruptly dumped into the catchment area of the Wivenhoe Dam, dam operators were forced to open the floodgates to save the dam, raising the Brisbane River well above normal height. The torrential dam outflow collided with the cyclonic low pressure storm surge rushing in from the sea in Brisbane’s most expensive business and residential district.
Colleges Crossing, pictured at the top of this article, is the main outflow of the Wivenhoe Dam, the water reservoir which supplies the state capital Brisbane. The water which passes through Colleges Crossing feeds into the Brisbane River, which in 2013 was a major contributor to inner city flooding. My home at the time became an island as spillway water flooded across the lowlands, cutting all the roads, and bringing misery to riverside property owners downstream of the dam.
My point is flood disasters in Brisbane have nothing to do with climate change. I doubt flood risk could ever be completely eliminated in a subtropical location like Brisbane, but floods could be mitigated by better flood control, including enlarging existing dams or building new dams. Larger dam capacity would give dam operators the confidence to run down water levels in the face of a dangerous rainfall event, even if they were not sure if the rain would hit the dam catchment, instead of clinging on to water until the last minute, then flooding the city of Brisbane with an emergency release to save the dam from catastrophic failure.
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