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Five major global “tipping points” are in danger of being crossed at current levels of warming, a new study warns, leaving humanity at an inflection point between two potential futures.

An international team of more than 200 researchers identified 26 natural processes or features at risk of being suddenly and irreversibly disrupted by climate change, including ice sheets, tropical rainforests, mountain glaciers, ocean currents and coral reefs. They found that the mass death of warm-water coral reefs is likely at current levels of warming (1.2C), while four other processes — the collapse of Greenland and West Antarctic ice sheets, disruption of the North Atlantic subpolar gyre circulation and abrupt thawing of permafrost regions — are considered possible.

The researchers also identified positive tipping points, including rapid improvement in battery technologies as electric cars become more popular — a development that could in turn could make the widespread use of renewable energy easier.

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The report is a “tale of two future paths for humanity,” lead author Tim Lenton, a professor of climate change and earth system science at Exeter’s Global Systems Institute, said in a press briefing. “We’ve basically left it too late for incremental action. Instead, we need to find and trigger what we’re calling some positive tipping points that accelerate action down an alternative pathway.”

The risks of irreversible disruptions are ramping up with every small increment of warming, Lenton said.

The report comes as global leaders and negotiators gather at the COP28 climate conference in Dubai, where many are clashing with oil execs and each other over how to reduce emissions. Progress thus far includes commitments from 20 countries to triple renewable energy capacity by 2030, a pledge by 50 oil companies to reduce methane emissions and forward momentum on a fund for loss and damage. But negotiators are struggling to agree on a path forward for coal, oil and gas, with countries like Saudi Arabia opposed to any commitment to phase down use of fossil fuels.

“We are now in a flat-out race between tipping points,” said Mike Berners-Lee, a professor at the Lancaster Environment Centre, who was not involved in the report. “This report is not just a robust piece of science; anyone reading it should be prepared to be filled with adrenaline for the urgency of the challenge we face.”

The report’s authors call for countries to commit to phasing out fossil fuels and speeding up their timelines for reducing emissions. They also advocate for prioritizing research into tipping points, the risks of which they say should be factored into assessments of climate change adaptation, into countries’ nationally determined contributions and into the global “stocktake” of progress against Paris Agreement goals that is taking place for the first time at COP28. Policymakers should also urgently focus on triggering positive tipping points, they added.

“Averting this crisis — and doing so equitably — must be the core goal of COP28 and ongoing global cooperation,” said Manjana Milkoreit, a researcher in the department of sociology and human geography at the University of Oslo, and co-author of the report. “Good global governance can make this happen, especially by triggering positive tipping points.”

Photograph: The Olivares Alfa glacier near Santiago, Chile, on July 5, 2019. Glaciers are at risk from tipping points caused by climate change. Photo credi: Tomas Munita/BloombergPhoto credi: Tomas Munita/Bloomberg

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