Climate Promises to Date Can Deliver Below 2°C, but Emissions Must Peak Before 2025

Countries’ climate action promises to date would be enough to keep average global warming just under 2°C, but only “if all conditional and unconditional pledges are implemented in full and on time,” a team of Australian scientists concludes in a paper published last week in the journal Nature.

The research finding reflects the 154 emission reduction commitments for 2030 and 76 longer-term pledges that countries announced by the end of last year’s COP 26 climate summit, The Independent reports. But “limiting warming not only to ‘just below’ but to ‘well below’ 2°C or 1.5°C urgently requires policies and actions to bring about steep emission reductions this decade, aligned with mid-century global net-zero CO2 emissions,” writes the research team led by Dr. Malte Meinshausen, director of the Australian-German College of Climate and Energy Transitions at the University of Melbourne.

“Peaking of global greenhouse gas emissions could be achieved this decade,” the scientists add. “But our results also provide a sobering assessment of how far current pledges are from limiting warming to 1.5°C.”

In a separate commentary, U.S. climate scientists Zeke Hausfather of the Breakthrough Institute and Frances C. Moore of the University of California, Davis warn that long-term targets are pretty much meaningless without short-term action, The Independent adds.

“It is easy to set ambitious climate targets for 30, 40 or even 50 years in the future—but it is much harder to enact policies today that shift energy systems towards a more sustainable future,” they write. “Long-term targets should be treated with skepticism if they are not supported by short-term commitments to put countries on a pathway to meet those targets in the next decade.”

The study appeared just a couple of days before lead scientists with the Intergovernmental Panel on Climate Change (IPCC) warned that one of their recent findings had been dangerously misinterpreted.

When the IPCC released its latest working group report in early April, it warned that global greenhouse gas emissions must peak “at the latest before 2025” to retain 50-50 odds of holding average global warming to 1.5°C. But most media outlets wrongly interpreted that to mean emissions can continue rising until 2025, the BBC writes.

“When you read the text as it’s laid out, it does give the impression that you’ve got to 2025, which I think is a very unfortunate outcome,” said IPCC lead author Glen Peters, senior researcher at the Centre for International Climate Research (CICERO) in Oslo. “It’s an unfortunate choice of wording that is, unfortunately, going to potentially have some rather negative consequences.”

The scientists chose that particular language because climate models work in five-year blocks, in this case from 2020 to 2025, explained IPCC lead author Dr. Joeri Rogelj, director of research at the Grantham Institute at Imperial College London.

“But when you look at the scientific data supporting this headline, it becomes immediately clear that any scenario in line with 1.5°C drops emissions from 2020 to 2025,” he told BBC. “Even for scenarios that limit warming to 2°C, this is also the case.”

In an opinion piece for The Guardian, Laurie Laybourn, associate fellow at the UK Institute for Public Policy Research, interprets the new Australian study as a cue to push governments and corporations for more ambitious emission reduction targets.

“To see this latest news in binary terms—either as a sign it’ll be OK or another depressing lie—misses its deeper significance,” he writes. “There is no target, agreement, or technology that can abruptly resolve the issue. Instead of ends, we should see these as means: signposts we can organize around, contest, and weave into an ever-widening mobilization of society that builds greater momentum for change.”