Australia is a continent that is arid over 70% of the land. Even in the 30% with rivers and trees, it is mostly known for its constant, very dangerous bush fires. But now we have to examine the three main types of flooding Australia has had.
Townsville, Qld
npr
Maryborough, Queensland
Floodlist
1.Riverine floods are the most common form. The two main contributors to riverine flooding are heavy rainfall and the land’s capacity to absorb water. When the land is saturated, the excess water flows into river systems and pushes the overflow onto the adjacent low-lying areas.
2.Flash floods occur from short intense bursts of rainfall, as during a thunderstorm. They can be particularly dangerous in urban areas where drainage systems cannot cope with the amount of water. As the water rises quickly, the drainage system may have insufficient capacity or time to cope with the downpour. Although flash floods are generally localised, they may pose a significant threat because of their short duration and unpredictability.
2.Flash floods occur from short intense bursts of rainfall, as during a thunderstorm. They can be particularly dangerous in urban areas where drainage systems cannot cope with the amount of water. As the water rises quickly, the drainage system may have insufficient capacity or time to cope with the downpour. Although flash floods are generally localised, they may pose a significant threat because of their short duration and unpredictability.
3.Coastal floods happen when a low-pressure system or strong onshore winds force sea levels to rise above normal levels, creating a storm surge that floods low-lying areas. All type of floods can be classified as minor, moderate or major based on their impact on communities and infrastructure.
Floods occur all over Australia, however different types of floods are common in different regions. Location determines what type of flooding is likely to experienced: river, flash or costal flooding or a combination. In the extensive flat inland regions, floods may spread over thousands of square ks and last several weeks.
The damage from floods can be varied, extensive and far reaching. The immediate impacts of flooding include loss of human life, long term damage to property, crop destruction and loss of livestock. The ongoing emotional impact is often terrible, as are the emotional stress and physical illness from waterborne diseases. Floods also damage power transmission and sometimes power generation, which then has knock-on effects caused by the loss of power.
The 2022 flooding was caused by a low pressure system over Queensland's southern coast that dragged in moisture from the Coral Sea in the north, raising it over the Queensland coastline. The low pressure trough delivered the rainfall but an area of colder air higher in the atmosphere was drifting in, making the atmosphere unstable and permitting moisture to be lifted up and dropped as heavy rain.
Hawkesbury River, New South Wales
Desdemona Despair
Lismore, NSW
The 2022 eastern Australia floods were one of the nation's worst recorded flood disasters that occurred in S.E Queensland and into coastal NSW. Brisbane suffered major flooding, as did the cities of Maryborough, Sunshine Coast, Gympie, Caboolture, Toowoomba, Ipswich, Logan City, Gold Coast, Murwillumbah, Mullumbimby, Grafton, Byron Bay, Ballina, Lismore, Central Coast and Sydney. Clearly as the system headed south, it turned into an East Coast Low near New South Wales/NSW’s Central Coast and Sydney. It will not surprise anyone that Sydney received more rainfall this October than any other October total in almost 170 years of record-keeping.
22 people so far have died in the 2022 floods. Across S.E Queensland, 1000 schools were closed in response to the flooding, evacuations were urgent and the public had to avoid non-essential travel. Food shortages occurred across the region due to the ensuing supply chain crisis in outback Queensland. The flooding caused the ground across S.E Queensland and Northern NSW to become saturated and vulnerable to even small amounts of rain.
While the amount of rain was less than the huge volumes seen in eastern states earlier in the year, the situation in the southern state of Victoria was made worse by the ground already being saturated. Victoria had experienced its wettest Aug since 2010, and Sept rainfall was above average across most of northern Victoria.
22 people so far have died in the 2022 floods. Across S.E Queensland, 1000 schools were closed in response to the flooding, evacuations were urgent and the public had to avoid non-essential travel. Food shortages occurred across the region due to the ensuing supply chain crisis in outback Queensland. The flooding caused the ground across S.E Queensland and Northern NSW to become saturated and vulnerable to even small amounts of rain.
While the amount of rain was less than the huge volumes seen in eastern states earlier in the year, the situation in the southern state of Victoria was made worse by the ground already being saturated. Victoria had experienced its wettest Aug since 2010, and Sept rainfall was above average across most of northern Victoria.
Residents in Echuca, Victoria
building sandbag levees to protect their properties
theguardian
Shepparton, Victoria
NYTimes
Shamrock Hotel, Rochester Vic
Watoday
A low pressure system travelled east over the nation, bringing the rain which hit southern Australia throughout Oct. As torrential rain swelled many of Victoria's major waterways to flood level, transport routes were cut, homes were inundated and communities were isolated. Victoria's floods were particularly severe along the Goulburn, Loddon and Campaspe Rivers, and on the Murray River. The third yearly La Niña event in a row was an important driver of rain in spring and summer. But the Indian Ocean electric dipole was really the main cause of the recent inland crisis.
La Trobe, Tasmania
weatherzone
South of the mainland in Northern Tasmania, some of the most significant flooding that they’ve had for years have subsided. But the weather system that pushed through in October has again lifted some of the northern river levels. And many of the catchments that were affected weeks ago have already received warnings that more rain was coming. Tasmanian residents in regions hit by recent floods are now preparing again as storm fronts move over the island state. Moderate flood warnings are in place to northern towns near Launceston, places already flooded.
Flooded areas across Australia, 2022
phys.org
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18 comments:
Horrible.
Brisbane's average rainfall is 1150 mm a year
Sydney’s average rainfall is 1210 mm a year
Melbourne’s average rainfall is 640 mm a year
Launceston’s average rainfall is 680 mm a year
So flooding in Brisbane and Sydney is less shocking than in the southern states.
Hi Hels - yes the rainfall you've had this year has been torrential and often still raining. Excellent article about the different types of flooding - I feel for all families who have lost a family member. Thanks for the interesting post - all the best Hilary
Australia's surrounded by oceans, so it's actually an island, a big continent island.
They say islands, big or small, are going to be heavily targeted by Climate Change.
The Greek island of Crete,for instance, was hit by a flash flooding at the beginning of October. It was unexpected, localised, following a storm, and it caused great damage.
There's nothing we can do about the climate, but we can greatly improve protection of people and property.
Deb
yes indeed..those rainfalls seem accurate, averaged over a longggg time.
But it leads me to ask whether the more northern cities were prepared for very heavy rains this year. Could the levies have been built ahead of time? Could the dams have been released earlier in the year so that the later overflows could have been averted? Could new houses NOT be built or renovated at sea level but instead up higher levels only. If I was a farmer, I would have had my cows and sheep moved long before they drowned.
Hilary
the families who lost their family members will never recover, sadly. But even those who lost their homes, crops and livestock will have lost their normal lives and their incomes. Hopefully the children will be welcomed into their new schools.
DUTA
I didn't mention climate change because I didn't want to turn readers off, before I turned them on to the urgency of the topic. And changes happen every year, in any case.
But this century the changes have been happening faster than ever before. The temperatures are changing; the rainfall is changing; La Niña and El Niño (oceanic and atmospheric phenomena) are unpredictable; and even the gorgeous Great Barrier Reef will be dead within a few years.
I wish I had written this. So well researched and as far as I can see, very accurate. If you've been to Echuca and stared up at the highest level wharf, it is hard to imagine in normal river height times how the Murray could ever rise to that level, but it does.
No, of course it is nothing to do with climate change. Esteemed conservative politicians and big business were telling us this not so long ago and that they were natural weather cycles. No reaction by humans was needed.
Andrew
I am definitely a Big City woman, but I lived in beautiful Bendigo for a few years and had responsibility for families as far as Castlemaine, Kyneton, Wedderburn, Echuca and Rochester. And I had my closest professional contact in Swan Hill.
It breaks my heart to see what is happening to the Loddon and Campaspe Rivers in particular.
Boa tarde minha querida amiga. Suas matéria desperta pelas catástrofes mundiais que estão se espalhando pelo mundo todo. Grande abraço carioca.
I worked in these regions as a contractor over the years especially serving Echuca region for over 8 years. It is quite depressing to see these images.
Luiz
correct...world catastrophes seem to be more vicious and more frequent, sadly. But we have to differentiate between human catastrophes (eg armies shooting civilian protesters) and natural catastrophes (eg bush fires, volcanoes).
Now we know that our states can suffer from flooding, even if it is only once every 30 years, we are obligated to mitigate the causes as best we can AND provide protection once the floods occur.
roentare
Echuca and its surrounding region is a lovely part of Victoria, I agree 100%. I have added a photo of Rochester, to show just how depressing the experience has been in Northern Victoria... as well as in the rest of the eastern states.
A good way to improve flood readiness is to understand how floods work, and then to examine adaptive solutions developed by communities facing similar situations in other countries. Every river behaves differently and responses should site-specific, as "Beyond a State of Sandbagging: what can we learn from all the floods, here and overseas" shows. The post also discusses What can communities do?
PreventionWeb
26 Oct 2022
Penny, Andrew and Martin
thanks for the late Oct 2022 post. I found this concept very interesting:"Engineered infrastructure, such as dams and levees, has encouraged us to live on floodplains with little regard for the impacts of climate variability. Dams and levees work within predicted parameters, but we can’t expect that predictability anymore. And planning regulations that restrict building on floodplains can be useful but are only part of the solution".
Unfortunately it was not clear to lots of Australians that infrastructure had encouraged us to live on floodplains.
Boa tarde. Obrigado pela visita e carinho. Bom final de semana com muita paz e saúde minha querida amiga.
Luiz
Thank you. Many countries and cities in the world have suffered terribly, so I don't want to suggest that Eastern Australia has suffered worse than elsewhere. But coming so soon after the Covid losses, I can't believe that so many people, animals, houses and businesses have been lost. Even today the emergency services were saving lives in Forbes and Wagga Wagga (NSW towns) on small boats.
Of course we can do something about Climate change , We have about 10 years to reduce emissions to keep it down as much as we can . I feel furious that we have wasted 10 years here in Australia and that we have some despotic toads on this planet who are waging war rather than attending to the huge task that is ahead for all of us even them . Having said that the light bulbs have gone to a hopeful glow rather than off and a lot is being done but still we have to battle the willfully ignorant and narcissitic tyrants who think of nothing but their own aggrandizement .
mem
I was never sure if people opposed to Climate Change legislation were merely ignorant, or actually nasty conservatives "who think of nothing but their own aggrandisement". But when a Conservative MP reported earlier this year that she crossed the floor to vote with Labour to enshrine a 43% emissions reduction target, it became clear. She had put herself under great pressure from her colleagues to oppose even a moderate emissions reduction target and so she still risks being dumped by her Party.
Australia's deadly floods and deadly bushfires should remain a clear message, even to Conservative politicians. Let alone in other countries which are worse off than we are.
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