by When Dorothea Mackellar wrote about flood rain more than a century ago, she could have anticipated nothing in the scope of the current flood in Queensland.
The downpour, which was crowned by the rain by the rain of ex-tropical cyclone dianne, has a phenomenal amount of water in outback cities and cities that flooded, causes access to communities and flooded inventory losses of more than 150,000.
The resulting floods of the interpreters in the boom-bust cycle, which referred to this dry landscape-filled dry flows and expanded over broad and flat levels, which has achieved scale that has not been observed since European colonization.
How extraordinary was the flood?
The professor of Griffith University, Fran Sheldon, a river ecologist specializing in dry land flow systems, says that the floods are “massive” and “probably at the extreme end of the boom”.
“These are flood areas that have not been flooded in European memory,” she says, although evidence from soil and fishing genetics indicate that this scale have already flooded.
It is expected to take weeks or even months in Germany to move downstream to South Australia towards Kati Thanda -Lake Eyre.
The catchment area of Kati Thanda’s river extends over 1.2 m square kilometers – more than one seventh of the Australian land mass – including parts of Queensland, South Australia, the Northern Territory and New South Wales. Rain and river flows are extremely variable and fluctuate between long dry periods and sporadic rainfall.
According to flood measuring devices, the huge water exceeded the 1974 event, which is considered the greatest flood in the history of Queensland. But it was still in the floodplain, says Sheldon and “only reached the edges”, where people thought it would work.
This was a natural phenomenon, says Sheldon, although the devastation of cities and municipalities was terrible.
“The nice thing about these river systems is that they are some of the last non -regulated rivers in the world. We only see rivers as rivers. There are no large dams in these systems. There are no massive irrigation industry. So that’s exactly what big rivers do.”
So much water, where does everything come from?
About two weeks ago, severe and relentless rain fell over normally dry inland areas of Queensland, when a slowly moving trough dragged tropical moisture in the interior.
The sky was briefly clarified this week before the remains of ex-tropical cyclone dianne continues to rain in decorated areas.
Rain records have fallen through the state.
Related: Bigger than Texas: the real size of the devastating floods of Australia
According to the Bureau of Meteorology, wide areas in Western Queensland received up to four times March average. In four days from 23 to 26 March-Hatten parts of the southern and southwestern Queensland more than their annual average precipitation.
The airport in Winton, Australia’s dinosaur capital, recorded 56 mm higher on March 26, 158 mm than the previous daily precipitation record for March. A day later, 177 mm fell onto the Dillalah station, at Mitchell Highway about 700 km west of Brisbane and broke his record by 31 mm. The pastoral rental agreement received so much rain in March – a total of 417 mm – it almost doubled its monthly rain record.
The office said that the catchment areas of Paroo, Bulloo, Cooper and Thomson had recorded their greatest floods for 50 years.
The persistent trough, together with the ex-tropical cyclone Alfred, led to the third most nobility of the state.
Dr. Andrew King, Associate Professor of Climate Science at the University of Melbourne, said when low -pressure systems were broadcast from the north, be it warm and moist and created perfect conditions for strong precipitation.
The floods in North Australia during the rainy season are not unusual, although it is unusual to see several extraordinary flood events.
While winds generally move throughout the country, King says that sometimes low -pressure systems linger and “hold on to the spot for a while” when there is a high -pressure system nearby. “When the systems hang around long enough, the flood tends to be worse.”
There is still no conclusive evidence of whether climate change contributes to these inpatient events, he says, although it is something, examine the researcher.
Climate change increases the amount of moisture that can keep the air, which can lead to heavier rainfall.
Could we have been prepared more?
Dr. John Macintosh, a water engineer and former national committee for water technology from engineers Australia, says that infrastructure such as dams, dikes or detours in Germany Lural Australia do little to reduce the effects if such huge volumes are involved in water.
More moisture in the atmosphere created the conditions for higher precipitation that could continue to spread in a flat landscape, he says.
“More water volume … means that we have larger areas that are affected,” says Macintosh, all increased by growing population groups, agriculture and industrial activities.
The governments improve their disaster management skills, but he says that more early warning and surveillance systems will reduce potential flood damage. Engineers can help by using rainfall, flood and river flow data and using the mapping to better predict the expected timing and the depth of flood events.
Where from here?
Most of the water via Cooper Creek and Georgina, the Diamantina River Systems, will finally penetrate Kati Thanda -lake Eyre.
The “large creeping water mass” moves at a hiking pace, says Sheldon. But as soon as Kati Tanger has achieved – in weeks or months – it will probably fill the lake, a rare event that only occurs a few times a century. “We see something pretty unique,” she says.
As the flood progresses, the wet of flows and filling of rivers and wetlands, nutrients and invertebrates will provide a finished source of food for fish and water birds.
“Many of these floodplain floors contain eggs with small invertebrates, the zooplankton that slips when they get wet. There is an immediate boom of this incredible source of food for fish, and they will simply be out there to celebrate and grow and grow again and the best of it.”
When the water finally reaches its goal, brine prawns slipped out of the salty sediment that provides millions of water birds with food.
“It’s not just Kati Thanda who is booming. All of these wetlands are covered with water birds and covered with fish and is also booming,” she says. “It will be spectacular.”
