The threat of intense heatwaves looms over the planet for the next thousand years, regardless of whether global emissions reach net zero, according to recent findings. However, postponing the achievement of this target could further intensify the situation.

Researchers from the ARC Centre of Excellence for Climate Extremes and CSIRO have created models projecting the frequency and intensity of heatwaves over the coming millennium. These models were based on scenarios where global net zero emissions are achieved between 2030 and 2060.

The study revealed that the later net zero is achieved, the hotter, longer, and more frequent heatwaves become. Additionally, lingering warming effects in the Southern Ocean could continue to exacerbate heatwave conditions, even after net zero is reached.

Remarkably, the simulations indicate that heatwave trends remain constant over the entire thousand-year period, showing no signs of returning to pre-industrial levels, even with net zero emissions.

In some areas, heatwaves could become even more severe if net zero is delayed until 2050 or beyond, highlighting the critical importance of timely climate action.

“While our results are alarming, they provide a vital glimpse of the long-term future, allowing effective and permanent adaptation measures to be planned and implemented,” she said.

“It’s also vitally important that we make rapid progress to permanent net zero.”

Co-author Dr Andrew King of the University of Melbourne said adapting to this future would be the work of “centuries, not decades”.

“Investment in public infrastructure, housing, and health services to keep people cool and healthy during extreme heat will very likely look quite different in terms of scale, cost and the resources required under earlier versus later net zero stabilisation,” he said.