‘Damned if we do but completely stuffed if we don’t’: heatwaves will worsen longer net zero is delayed | Climate crisis

New research suggests heatwaves will become hotter, longer and more frequent as net-zero emissions are reached globally.

scientists ARC 21st Century Weather Center of Excellence and Australia’s national science agency CSIRO studied the differences at each five-year delay in reaching net zero between 2030 and 2060, simulating how heatwaves will respond over the next 1,000 years.

Research published in the journal Environmental Research EnvironmentIt found that delaying net zero for countries near the equator until 2050 would result in at least one heat wave event per year that breaks current historical records.

The study also suggests that heat waves will not return to pre-industrial conditions for at least a millennium after net zero is reached; This “seriously questions the general belief that conditions after net zero will begin to improve for the foreseeable future.”

“The problem with net zero and heat waves is that we’re damned if we do it, and completely stuck if we don’t,” said the study’s lead author, Prof Sarah Perkins-Kirkpatrick from the Australian National University. “We’re already locked in to a certain amount of warming.”

Sign up to receive climate and environment editor Adam Morton’s Clear Air column as a free newsletter

He said fixing global warming at 1.5 or 2°C would still lead to impacts “that we have not yet experienced, including worse heatwaves.” “The point is that if we delay net zero for up to 30 years, or even longer, these effects will get worse. We’re already locked in some, but the longer we leave net zero, the worse it will be.”

“[In Australia] “The coalition is basically saying: net zero is useless, it’s pointless, it’s not worth it, it’s going to cost us a lot of money,” he said. “If we don’t get to net zero by 2050, it’s going to cost us even more.”

“The positive side of this kind of work, if there is any, is that we have time to adapt… so when these heat waves occur, we are as prepared for them as possible,” he said. “We know the effects of heatwaves; there is a lot of information about the effects on health, the effects on the ecosystem and the effects on financial services.

“What these adaptation strategies will look like is not yet known,” he said. “These talks can begin now.”

The modeling was done using Australia’s global climate simulator, known as Access, and defines a heatwave as at least three consecutive days with temperatures above the 90th percentile for maximum temperature.

Climate change scientist and Climate Council councilor Prof David Karoly, who was not involved in the research, said the findings were not surprising.

“There is a clear relationship between cumulative carbon dioxide emissions in the atmosphere and global average temperatures,” he said.

Karoly added that the results of the study are interesting, but one caveat is that the geographic representation of Australia and other regions in the Access model is at a lower resolution than in other climate simulators, so there are uncertainties in the modeling regarding potentially important processes such as precipitation changes.