What is rain bomb? The rare weather phenomenon that caused mayhem in Australia

The rain has continued unabated in many parts of the Australian city. More than 1.5 metres of rain, close to the average annual rainfall, has come down since Thursday in many parts.

(Credits: Reuters)

New Delhi: Australia is currently facing catastrophic weather events as a result of global warming. Australia’s third-most populous city, Brisbane, was underwater Monday after heavy rain brought record flooding to some east coast areas and killed eight people. Large parts of Queensland and New South Wales are experiencing flash floods that have caused widespread major property damage as rainfall exceeds annual averages in just a few days. 

In the wake of a severe storm, over 1,400 homes in the capital of Queensland state were at risk of flooding while more than 28,000 homes were without power statewide. 

Queensland Premier Annastacia Palaszczuk said the rainfall over Brisbane had been extraordinary since November. "We never expected this rain. This rain bomb is just really, you know, it's unrelenting ... It's just coming down in buckets," Palaszczuk said. 

What is a rain bomb? 

A rain bomb event occurs when the air hits the ground at such force that it creates tornado-strength winds. A rain bomb fell in Australia’s third-most populous city, Brisbane and knocked over power lines and caused widespread destruction in a matter of hours. 

The rain has been fierce and has continued, unabated in many parts of the Australian city. More than 1.5 metres of rain, close to the average annual rainfall, has come down since Thursday in many parts.

The recent flooding in Brisbane is the worst since 2011 when the city of 2.6 million people was inundated by what was described as a once-in-a-century event.

Multiple emergency flood alerts were in place for Brisbane suburbs, where 2,145 homes and 2,356 businesses were submerged on Monday. Another 10,827 properties were partially flooded above the floorboards.

The Brisbane River peaked on Monday at 3.85 meters (12 foot, 3 inches), officials said. That was 61 centimeters (2 feet) below the 4.46 meter (14 foot, 3 inch) flood level reached in 2011, officials said.

According to the PTI reports, about 700 people were asked to evacuate from the city of Gympie on Saturday after the Mary River system surged beyond 22.06 m (72.4 ft) for the town's worst flood since the 1880s. Meteorologists said the deluge and thunderstorms would continue through Monday, before starting to ease off in Queensland, but moving south to New South Wales, where some communities at risk in its northeast have been told to evacuate.

The risk of riverine and flash flooding was "very real over coming days," said Steph Cooke, the state's emergency services minister. Brisbane Lord Mayor Adrian Schrinner said the floods are “very different" to 2011 because the rain pummeled the region for five days. In 2011, the rain had stopped days before the Brisbane River peaked and authorities had warned for several days of flooding downstream.

Additionally, Lismore was bracing for its worst flooding on record. Downtown Lismore was inundated on Monday after days of unrelenting rain and 15,000 people had been evacuated, officials said.

'Australia facing more floods due to global warming'

The Intergovernmental Panel on Climate Change (IPCC) on Monday published its latest report at a time when large parts of Queensland and New South Wales are experiencing flash floods that have killed eight people and caused widespread major property damage.

Mark Howden, the co-author of the IPCC report and director of the Institute for Climate, Energy and Disaster Solutions at Australian National University (ANU), said that adaptation policy was key to mitigating the effects of climate change.

"Climate change impacts are here. They matter. They are mostly negative but if implemented, adaptation can take the edge off them," he said in a statement.

"The latest IPCC report makes one thing crystal clear: adaptation policy, finance and practice have to be stepped up urgently if our systems are to keep pace with climate change. Adaptation action is a core foundation of sustainable development."

His ANU colleague, Ruth Morgan, was a lead author on the IPCC report`s chapter on water and is now the director of the ANU Center for Environmental History.

She said climate change was likely to bring more rainfall in the country`s north including Queensland but less in key agricultural areas in the south. "Climate change is already changing Australia`s rainfall; that is, where it rains, when, and how much," Morgan said.

"We`re seeing more rainfall in the north, while in the south, droughts are becoming both more likely and severe."

"Less rain means that there will be less streamflow into the water catchments that provide water for Australia`s capital cities, so we will need to think carefully about where our water comes from and how we use it."

(With agency inputs)