A handout photo taken and received on March 31, 2022 from the New South Wales (NSW) State Emergency Service shows floodwaters inundating the northern NSW city of Lismore. ( AFP PHOTO / NEW SOUTH WALES STATE EMERGENCY SERVICE / Handout)

Cloud seeding did not cause deadly Australian floods: experts

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As floods devastated Australia's east coast, social media posts accused a pilot of causing the disaster through cloud seeding, a weather modification technique that involves dropping a rain-inducing chemical into clouds. However, experts told AFP the floods were naturally occurring and cloud seeding cannot cause flooding. The pilot's aviation company said it was conducting aerial surveys for a mapping firm that provides images to insurers and emergency services.

"LISMORE - 31 Mar 2022 While cloud seeding was in progress!" reads a Facebook post from April 2 shared alongside a photo of a town swamped in murky water.

At least 22 people have been killed and tens of thousands forced to flee their homes on Australia's east coast since early February when waterways burst their banks following torrential rain.

The town of Lismore in New South Wales was devastated by record 14.3-metre (47-foot) floods, which swept away cars and left locals stranded on the roofs of their homes.

"A pilot from Handel Aviation in Cessna 210N Centurion VH-JIL did a breakfast time cloud seeding run over Lismore South & Ballina today while sightseeing the massive flood below him," the Facebook post adds.

It claims the photo is "proof of weaponised geoengineering used against the Lismore population today".

Cloud seeding is a weather modification technique that involves dispersing a substance into the clouds to prompt rain.

A screenshot of the Facebook post, taken April 8, 2022.

The claim spread across various platforms, including Facebook, Twitter, and Telegram.

However, the claim weather modification contributed to flooding in Lismore is false, experts told AFP.

Flood conditions

Steven Siems, a professor who leads a team studying clouds and precipitation at Monash University in Australia, said cloud seeding cannot cause flooding.

"Cloud seeding is not that effective, people do it only under very special circumstances," he told AFP.

He said cloud seeding in Australia has only "demonstrated any statistical significance" in the colder environments of the Snowy Mountains and parts of Tasmania.

Nina Ridder, who studies climate extremes at the University of New South Wales, said the flooding in northern New South Wales was caused by wetter than usual conditions related to a La Niña weather system.

La Niña occurs when Pacific trade winds strengthen, increasing water temperatures and rainfall around northern Australia and the Western Pacific, she said.

"This means all the catchments were full, all the river basins were full, or quite near to full, and the earth was already saturated," she told AFP. "So the additional rainfall which landed on the area was likely to cause a flood."

'Threatening stuff'

Handel Aviation's managing director Mark Handel told AFP the company had deployed aircraft to take photos of flooding for a mapping company called NearMap.

He said the firm was not involved in any cloud seeding operations and had received more than 100 threats due to the misinformation circulating online.

"We had really violent threatening stuff coming through. Like: ‘we have the pilots' names, we know where you live, you're going to pay for this,’ kind of stuff," he told AFP.

In a statement, the firm said it "operated aerial photography aircraft only" and that its flights over flooded areas of New South Wales and Queensland were to take photos "used to assess the damage caused by recent weather events".

A representative for NearMap said it had contracted Handel Aviation as part of a wider initiative to capture aerial images following natural disasters.

"These aerial captures are commissioned after major weather catastrophes and natural disasters, including following the recent East Coast flooding," the spokesperson told AFP.

It said the images are provided to emergency services, government, and insurers.

Aerial images of the floods credited to NearMap were included in an ABC news report published on March 5, 2022.