Climate experts are predicting a long and hot summer in Australia, with an increased risk of drought and heatwaves, despite the lack of an El Nino declaration from the Bureau of Meteorology. This prediction comes after a record-breaking winter in 2023, with national mean temperatures 1.53 degrees above the average from 1961 to 1996.
According to climate scientist Sarah Perkins-Kirkpatrick from UNSW Canberra, global warming is the driving force behind these hotter conditions. She states that there is no other explanation. While she does not believe it will be the worst heatwave season on record, she does believe it will be a bad one.
The months of June, July, and August were the warmest on record since national records began in 1910. However, the eastern seaboard has experienced back-to-back La Nina cycles, which have brought cooler and wetter conditions. This has resulted in above-average rainfall over the past two years, providing enough moisture to buffer against the onset of drought.
While the Bureau of Meteorology has issued an El Nino alert with a 70% chance of the weather system forming, they are waiting to see if the atmospheric conditions necessary for its declaration will occur. The bureau has been an outlier among global weather agencies in not declaring an El Nino event, which is typically associated with hot, dry summers in southeast Australia and an increased risk of drought and bushfires.
The bureau is specifically waiting to see the weakening of trade winds, which is a second phenomenon associated with El Nino events. This breakdown of usual wind patterns prevents moisture from reaching Australia’s east coast.
Professor Mark Howden from the Australian National University’s Institute for Climate, Energy and Disaster Solutions acknowledges that not all the El Nino markers used by the bureau are in place. However, he points out that temperatures in the eastern Pacific Ocean are edging towards uncharted territory. He believes it is more important to focus on the functional importance of these events rather than getting hung up on definitions.
Considering the record-breaking heatwaves and bushfires experienced in the northern hemisphere this year, it is likely a similar scenario will play out in the southern hemisphere for Australia. Hot water is pooling in the central Pacific Ocean, leading to hotter temperatures than average.