2 days Ago By Nick O'Malley
The world experienced its hottest year on record and Australia its second hottest in 2024, with the average global temperature reaching 1.6 degrees above the pre-industrial era years before scientists expected to see such an increase. The 10 hottest years on record have happened in the past 10 years, including 2024, said United Nations Secretary-General Antonio Guterres in his message for the New Year.
Heat shimmers over the Sturt Highway west of Hay, NSW where temperatures climbed above 40 degrees before midday in December. Credit: Nick Moir “Today I can officially report that we have just endured a decade of deadly heat. This is climate breakdown – in real-time.
We must exit this road to ruin – and we have no time to lose.” Climate change contributed to the deaths of at least 3700 people and the displacement of millions in 26 weather events studied by World Weather Attribution (WWA), a group of researchers from major institutions around the world studying the links between climate change and weather extremes. “It’s likely the total number of people killed in extreme weather events intensified by climate change this year is in the tens, or hundreds of thousands,” said WWA in its end-of-year report.
It found that climate change added 41 days of dangerously high temperatures last year, including a 50-degree day leading to a surge in hospitalisations in Mali, and contributed to record-breaking floods in several countries and severe drought across South America. Professor Mark Howden, director of the Institute for Climate, Energy & Disaster Solutions at the Australian National University, said that 2024 was Australia’s second-hottest year since the Industrial Revolution, and that the pace of warming had shocked scientists. “If you went back a few years, and if you made a proposal we’d be here at 1.
6 degrees by now, people would have said, well, that’s a bit extreme. You would have been pretty much alone saying that.” According to the Australian Bureau of Meteorology, the national mean temperature last year was 1.
46 degrees above the 1961-90 average, while in 2019 it was 1.51 degrees higher and in 2013 it was 1.34 degrees higher.
Howden said a step-change in global average temperatures since mid-2023 had become a focus for research around the world. The cause is likely to be complicated, but one culprit might be a reduction in pollution from shipping due to new regulations outlawing dirtier fuels. Extreme heat accelerated fires in California in August 2024.
Credit: Nick Moir Until the new regulations came in, exhaust from shipping contained particles around which low-level clouds formed, shading the sea and reflecting radiant heat back into space. Howden said he expected temperatures in Australia to remain high this year, but not break new records due to the cooling impact of a weak La Nina in the Pacific Ocean. Last year global fossil carbon emissions were at their highest level in history despite years of efforts to restrain them via the Paris Agreement.
The amount of carbon dioxide in the atmosphere was recorded at 420 parts per million by NASA in November. Before the Industrial Revolution, carbon levels were consistently around 280 parts per million for almost 6000 years of human civilisation. “My expectation would be temperatures similar to 2023 on average across 2025, so probably not record-breaking,” said Howden.
“Over the longer term, I think what we’re going to see is continuing increases in temperature, because we’ve got continuing greenhouse gas emissions and continuing build-up of greenhouse gasses in the atmosphere. “At the moment, we’re nowhere near slowing that down.” He said Australians could expect to see hospital admissions and deaths rise among the elderly and infirm from heat stress, increased fire threats, energy systems falter and even a spike in crime rates on the increasing number of days of extreme temperatures.
Most of Australia has an 80 per cent chance of hot, above-average temperatures throughout summer. Credit: Bureau of Meteorology He said the physics of climate change was apolitical and called on all political leaders to pursue policies to rapidly reduce emissions. In November, the World Meteorological Organisation projected that total carbon dioxide emissions for 2024 would be 41.
6 billion tonnes in 2024, up from 40.6 billion tonnes in 2023. Emissions from Europe and the US have trended down in recent years, while emerging economies such as India have increased emissions – as allowed for in the Paris Agreement, which acknowledged that most greenhouse gases accumulated in the atmosphere had been emitted by advanced economies as they industrialised.
Under the terms of the Paris Agreement, the world agreed to an effort to stabilise the climate at well below 2 degrees above the pre-industrial average and as close to 2.5 degrees as possible. The exposed bed of the Ardingly Reservoir during a 2022 heatwave in England.
Credit: Carlos Jasso/Bloomberg Though the world has now experienced a full calendar year with average temperatures over 1.5 degrees, under the terms of the Paris Agreement, the target will not be considered to have been passed until average temperatures have stayed over the threshold for some years. Get to the heart of what’s happening with climate change and the environment.
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