'Unprecedented dieback': Alarming report warns Earth reached 'point of no return'

Less than two years after researchers at the University of Exeter in the United Kingdom warned that the world was nearing numerous climate tipping points, a report out Monday warns that one such “point of no return” has already been reached, with warm-water coral reefs “experiencing unprecedented dieback.”

Surging global temperatures, especially in recent years, have pushed the world’s coral reefs into a state of widespread decline, with the worst bleaching event on record taking place since 2023. More than 84% of the world’s reefs have been impacted.

In the Global Tipping Points Report 2025 released Monday, the researchers warned that “the central estimate” of coral reefs’ “tipping point of 1.2°C global warming has been crossed,” with planetary heating now at about 1.4°C above preindustrial levels.

The warming waters have caused widespread bleaching of coral reefs, which impacts the nearly a million species of marine animals and organisms that rely on them to support some of the planet’s most diverse ecosystems.

“Unless we return to global mean surface temperatures of 1.2°C (and eventually to at least 1°C) as fast as possible, we will not retain warm-water reefs on our planet at any meaningful scale,” the report says. Minimizing non-climatic stressors, particularly improved reef management, can give reefs the best chance of surviving under what must be a minimal exceedance of their thermal tipping point.“

The decline of coral reefs also leaves coastal communities without natural barriers against storm surge, compounds the overfishing crisis by depriving fish of a habitat in which to reproduce, and impacts thousands of jobs and billions of dollars in reef tourism each year.

”As we head into the COP30 climate negotiations it’s vital that all parties grasp the gravity of the situation.“

”We can no longer talk about tipping points as a future risk,“ Steve Smith, a social scientist at the University of Exeter and a lead author of the report, toldNature. ”This is our new reality.“

The arrival of the tipping point necessitates immediate, significant reductions in fossil fuel emissions that are driving planetary heating in order to return to a global mean surface temperature of 1.2°C over preindustrial temperatures, but climate scientist Bill McGuire did not mince words Monday regarding the likelihood of mitigating the damage already done to coral reefs.

”We won’t reduce temps to 1.2°C as soon as possible, so this is the death knell for most of the world’s stupendous reef communities,“ said McGuire. ”Other tipping points will follow.“

The report notes that the world is still headed toward other climate tipping points, namely the ”large-scale“ degradation of the Amazon rainforest, which is projected to ”weaken global climate regulation“ and accelerate biodiversity loss; the melting of mountain glaciers like Áakʼw Tá Hít in Alaska; and for the Atlantic Meridional Overturning Circulation (AMOC), which regulates the climate by transporting warmer waters from the tropics to the northern Atlantic Ocean, whose likelihood of reaching a tipping point ”increases with global temperature“ rise.

Without rapid cuts to greenhouse gas emissions, the Global Tipping Points report says, the upper threshold of global temperature rise for coral reefs of 1.5°C is likely to be reached within 10 years.

”We are going to overshoot 1.5°C of global warming probably around 2030 on current projections,“ Tim Lenton of the University of Exeter’s Global Systems Institute toldThe Guardian.

Manjana Milkoreit, a co-author of the report and political scientist at the University of Oslo, told Nature that ”we have the knowledge regarding how to stop the Earth from reaching more tipping points.“gr

”What we need is a kind of governance that matches the nature of this challenge,“ she said.

The report also acknowledges ”positive tipping points“ that could have runaway impacts on the ability to rapidly draw down greenhouse gas emissions, such as the widespread adoption of regenerative agricultural practices and an acceleration in the transition toward electric vehicle and solar power use.

”Solar PV panels have dropped in price by a quarter for each doubling of their installed capacity. Batteries have improved in quality and plummeted in price the more that are deployed,“ reads the report. ”This encourages further adoption. The spread of climate litigation cases and nature positive initiatives is also self-amplifying. The more people undertaking them the more they influence others to act.“

Lenton told The Guardian that ”the race is on to bring forward these positive tipping points to avoid what we are now sure will be the unmanageable consequences of further tipping points in the Earth system.“

As Common Dreamsreported last week, global progress toward transitioning away from fossil fuels and expanding the use of renewable energy is surging worldwide—but the US has been left out this year under President Donald Trump, with a major spending bill imposing new fees on solar and wind development and boosting drilling on public lands while the US Department of Energy is investing $625 million in coal.

The Global Tipping Points report was released four weeks before global leaders are set to meet in Belém, Brazil for the 30th Conference of the Parties to the United Nations Framework Convention on Climate Change (COP30), where policymakers will be asked to contribute to a Granary of Solutions: ”a reservoir of concrete tools and initiatives—scalable, replicable, and aligned with the Paris Agreement—that connect ambition with implementation“ in order to trigger ”positive tipping points of transformation leveraging solutions that already exist.“

”As we head into the COP30 climate negotiations it’s vital that all parties grasp the gravity of the situation,“ Mike Barrett, chief scientific adviser at the World Wide Fund for Nature in the UK and a co-author of the report, told Yale Environment 360. ”Countries must show the political bravery and leadership to work together and achieve them.“