BOM's annual climate statement confirms 2019 as country's hottest, driest so far

2019 hottest, driest so far

THE Bureau of Meteorology (BOM) has confirmed what many in agricultural regions in Australia would have suspected - that 2019 was the hottest and driest year over Australia as a whole since official records began.

Texas recorded its lowest rainfall on record with 163.3mm and also it's highest annual mean daily maximum temperature of 29.1. Goondiwindi's lowest ever rainfall was 266.1mm in 1915 compared to 268.1mm in 2019.

In handing down its Annual Climate Statement, the BOM said Australia's average mean temperature in 2019 was 1.52 °C above average, making it the warmest on record since consistent national temperature records began in 1910 and surpassing the previous record in 2013 of 1.33 °C above average.

Meanwhile the national average rainfall total in 2019 was 277 mm, the lowest since consistent national records began in 1900.

The previous record low was 314 mm set during the Federation drought in 1902.

Bureau of Meteorology head of climate monitoring Karl Braganza said 2019 was consistently warm, interspersed with periods of extreme heat.

"January last year was the warmest month Australia has ever recorded, while just a few weeks ago in December, we saw the Australia-wide record hottest daily average maximum temperature broken multiple days in a row," Dr Braganza said.

He said the heat, combined with the marked rainfall deficiencies, had combined to exacerbate the impact of drought and also fire. Various drivers were behind the annus horribilis, including the much-publicised Indian Ocean Dipole (IOD) positive event. However, Dr Braganza said there were other factors at play.

"We also saw the influence of a rare Sudden Stratospheric Warming event high above the south pole, which acted to push our weather systems northward and compound the warmer and drier than average conditions over southern Queensland and New South Wales during spring, amplifying the fire weather."

He also said climate change was playing a part.

"The other key factor at play is that Australia's climate has warmed by more than a degree since 1910, which means very warm years like 2019 are now more likely to occur, while the trend in recent decades has been for drier winter and spring seasons in the south."

National Farmers' Federation (NFF) president Fiona Simson said the report highlighted the difficulties facing farmers across the country.

"There's been no escaping the challenges of the past 12 months," Ms Simson said.

"2019 was a horror year for so much of the industry, with an escalation in the long-running drought bookended by devastating floods and fires," said Ms Simson.

"The bushfires of the past few weeks have laid bare just how hot and dry 2019 was."

However, there have been some tentative causes for optimism over the past month.

In recent weeks, some of the key drivers of the recent warm and dry patterns over Australia, such as the IOD positive, have eased.

As a result, Dr Braganza said rainfall for the coming months is expected to be average to below average in the east, while wetter than average conditions are possible over much of WA and SA.

"Unfortunately the outlook is not indicating a widespread return to wetter than average conditions over drought and fire affected parts of eastern Australia," he said.

"But with the likely return of the monsoon by mid-January for northern Australia, it's raises the chances that we could see some periods of higher rainfall move south in the coming months."