Heavy rainfall continues to plague parts of Australia, with some states having already reached their usual annual records.
After months of rain, flooding and wild weather, some of us are asking when it will come to an end.
Dr Karl Kruszelnicki has explained when the wet weather is expected to stop – and it’s not good news.
Why has there been so much rain?
Dr Karl explained four reasons for the heavy rainfall across Australia which has caused multiple flood crises in both New South Wales and Queensland.
The first reason is “hot water evaporates more than colder water”.
Australia is surrounded by pools of hot water so working on the theory it evaporates faster, we’re more likely to experience it when it comes back down.
“In Australia we have two pools of hot water up against our coast, La Nina on our east coast and on the west coast we have what they call the Indian Ocean Dipole and that is warm so it will evaporate,” Dr Karl said.
Then there is also the Southern Annular Mode which Dr Karl explained to be a bunch of cyclones “continuously going around the South Pole”.
“When they snug in you get blizzards on the Antarctic, when they go out you get cold weather patterns coming across Australia,” he said.
This can cause a low-pressure system to travel north to Australia which can then collide with a high-pressure system before moving out to sea, which creates an atmospheric river.
An atmospheric river refers to long narrow regions in the atmosphere which act like a river transporting large amounts of water vapour.
Dr Karl said this atmospheric river is what caused the downpour in Brisbane and the subsequent devastating floods earlier this year.
“That dumped eight cubic km of water on Brisbane in three days,” he said.
He added that’s the equivalent of 16 Sydney harbours.
Dr Karl didn’t hesitate to be the bearer of bad news with the heavy rain expected to continue until at least June, and it may get worse before it gets better.
“We’re stuck in the short term with a couple of months,” he said.
“It looks like it’s going to get worse.
“Maybe until June then things are up in the air.”
This means Australians may be facing the ongoing wet weather for a good part of this year as experts also predict La Nina is not going away anytime soon.
“La Niña has a 59 per cent chance of continuing through the Southern Hemisphere’s winter and a 50 to 55 per cent chance of persisting through the Southern Hemisphere’s spring,” Weatherzone said, referring to forecasts from US National Weather Service’s Climate Prediction Centre (CPC) and Columbia University’s International Research Institute for Climate and Society (IRI).
What can we do to change it?
Dr Karl said the reason for these intense weather systems that bring unpredictable weather is global warming.
“We can stop and reverse global warming which is the cause of it all we can drop our carbon emissions by 95 per cent in 10 years if we decide to,” he said.
“Whether we decide to or not depends on the influence of the fossil fuel companies.
“We can reverse global warming and bring temperatures back to what they were in the 20th century.”