Winter is upon us, so it’s time to bring out the oversized scarf, the beanie, and generally rug up warm. Or is it? This winter that might not be the case. If your idea of a perfect chilly season is cozy nights under a blanket, seeking out roaring fireplaces and a smattering of snow away from the slopes, then it’s bad news.
The Bureau of Meteorology (BOM) has said winter 2021 is likely warmer across much of Australia, including the capitals. There could even be a risk of bushfires in some areas. It’s part of a warming trend that’s spanned the last two decades.
But there is a surprise in the works. One of Australia’s most prominent climate drivers has retreated to neutral, which means hot waters north of the country could have a much more significant impact. Expect increased rainfall through the winter months – that’s excellent news for those in areas that have suffered from prolonged drying.
Australia’s cold autumn
Looking back, autumn was the coldest in Australia since 2015. “Cool conditions would have been felt particularly keenly by residents in inland NSW, who recorded minimum temperatures one to two degrees below average,” BOM climatologist Dr. Lynette Bettio said.
It was wet, too, with NSW and southern Queensland seeing deadly and devastating floods. “NSW had its second wettest March on record, with the extreme rainfall and severe flooding late in the month,” she said.
That’s meant water storage is generally in good nick, with the Murray Darling basin holding 20 percent higher than this time last year. However, much of southern Australia missed the heaviest rains. In parts of Victoria, Tasmania, and South Australia, soil moisture levels are below average.
What’s leading to a wetter winter?
The La Nina climate driver, which helped drench much of the east, is now way back in the rearview mirror. “Our climate drivers are currently neutral, meaning we’re not getting El Nino or La Nina bringing particularly dry nor particularly wet conditions to the continent,” Dr. Bettio said.
Therefore, like warm waters off Australia’s north coast, other factors could have a much more significant effect than might happen in a usual winter. “That could result in a wetter than average dry season across much of northern Australia, but as it is dry season, rainfall totals will not be high,” she said.
The moisture from the north could funnel its way down through the continent. June to August should see above-average rainfall across the Northern Territory, SA, Queensland, and NSW. Winter is usually the driest season of the year away from tropical areas.
More average conditions or even drier weather is a distinct possibility for Victoria, Tasmania, and Western Australia away from the tropical north.
Dr. Bettio said this was consistent with observations from the past 20 years, which showed a trend towards drier than average conditions in Australia’s south during autumn and early winter.
BOM data shows that excellent season rainfall has been declining in the southwest and southeast for 17 of the last 20 years by about 12 percent. But in the north, rainfall has increased.
This is partly blamed on climate change. “Climate change is playing a role in drying out winters in the southeast,” Dr. James Goldie from the Monash University Climate Change Communication Research Hub told news.com.au.
“It’s not the only thing influencing our rainfall, but we should be prepared for the possibility of more dry years ahead.” A warm wet season in the NT has resulted in significant vegetation growth. That means there is an increased fire risk for areas around Darwin during the dry season.