The Earth has crossed a daunting threshold in its climate journey.
The planet has officially reached its first climate tipping point. Constantly increasing ocean temperatures have now driven corals globally beyond their survival limits, resulting in an unprecedented loss of coral reefs and endangering the livelihoods of nearly a billion people, according to a new report published on October 13.
Even under the most hopeful warming scenario — in which global warming is limited to 1.5 degrees Celsius above pre-industrial levels — all warm-water coral reefs are almost guaranteed to exceed a critical point of no return. Researchers have described this as “one of the most urgent ecological losses facing humanity,” as stated in the Global Tipping Points Report 2025.
The decline of coral reefs is only the beginning, metaphorically speaking.
“Since 2023, we’ve experienced over a year with temperatures exceeding 1.5 degrees Celsius above the preindustrial average,” noted Steve Smith, a geographer at the University of Exeter specializing in tipping points and sustainable solutions, during a press conference prior to the report’s release on October 7. “It now appears inevitable that we will overshoot the 1.5-degree C limit, potentially as soon as 2030. This places the world in a precarious position, facing increasing risks and more tipping points being surpassed.”
These tipping points represent irreversible changes that could push the world into a new climate state, initiating a cascade of consequences. Depending on the degree of future warming, we may see widespread decline of the Amazon rainforest, the falling of the Greenland and West Antarctic ice sheets, and — most alarmingly — the possible failure of the Atlantic Meridional Overturning Circulation, or AMOC.
Cascading Consequences
Researchers indicate that global warming has already pushed coral reefs past their ability to adapt. Under existing climate policies, we may see warming reach approximately 3 degrees Celsius within a few decades, which could trigger the collapse of the West Antarctic Ice Sheet, the retreat of mountain glaciers, and the collapse of an ocean current near Greenland known as the subpolar gyre. The fate of the Amazon rainforest is intricately linked to both climate change and deforestation rates, while the trajectory of Atlantic ocean circulation remains uncertain under current warming forecasts. This graphic illustrates the warming thresholds for various parts of the climate system; beyond these thresholds, each system will dramatically shift into a different climate state.
the landmark Paris Agreement, where nearly all countries pledged to limit greenhouse gas emissions to keep global warming well below 2 degrees Celsius by 2100 — with a preference to keep it under 1.5 degrees Celsius to mitigate many of the dire impacts of climate change.
However, “we are witnessing a regression in climate and environmental commitments by governments and businesses alike,” stated Tanya Steele, CEO of the UK branch of the World Wildlife Fund, which organized the press event.
This report is the second assessment of tipping points produced by a global consortium of over 200 researchers from more than 25 institutions. The timing of the report’s release aligns with ongoing preparations for COP30, the annual United Nations Climate Change Conference, as ministers gather in Belém, Brazil on October 13.
In 2024 alone, there were around 150 extreme weather events unprecedented in severity, including the worst drought recorded in the Amazon. Holding the conference near this essential rainforest provides a chance to raise awareness about this critical tipping point, Smith remarked. Recent studies suggest that the rainforest “is at an increased risk of significant dieback than has been previously understood.”
This is due to factors beyond just warming; it’s the combination of deforestation and climate change that poses a significant threat to the forest. A mere 22 percent deforestation in the Amazon could shift the tipping point for temperature rise down to 1.5 degrees Celsius, the report indicates. Currently, deforestation in the Amazon is around 17 percent.
On a more positive note, Smith added, “We have also achieved at least one major positive tipping point in the energy sector.” Positive tipping points, he explained, are transformative shifts that lead to a series of beneficial effects. “Since 2023, there has been rapid progress in the adoption of clean technologies globally,” particularly with electric vehicles and solar cell technology. Concurrently, battery costs for these technologies are declining, creating a reinforcing cycle of advancement,” Smith said.
However, the current challenge goes beyond merely reducing emissions or capturing carbon from the atmosphere, warns report co-author Manjana Milkoreit, a political scientist at the University of Oslo focused on Earth system governance.
A comprehensive transformation in how governments approach climate change and mitigation is crucial, Milkoreit and colleagues argue. The challenge lies in the fact that existing governance structures, national policies, regulations, and international agreements — including the Paris Agreement — were not designed with tipping points in mind. They are meant to manage gradual changes rather than sudden, cascading impacts across multiple systems.
“What we are stating in the report is that these tipping processes present a unique kind of risk,” which is so significant it can be difficult to fully grasp, Milkoreit explains.
The report details several necessary actions that decision-makers must take promptly to prevent crossing more tipping points. Urgently reducing emissions of short-lived pollutants like methane and black carbon is a fundamental step to buy time. Additionally, there is an immediate need to enhance efforts to remove carbon from the atmosphere on a large scale. At both governmental and individual levels, the focus must increase on creating sustainable global supply chains, which includes minimizing demand for products linked to deforestation.
Furthermore, governments need to quickly formulate mitigation strategies capable of addressing multiple climate challenges simultaneously. The report emphasizes that this is not merely a selection of options: it is a required action plan.
Undertaking these changes represents a monumental challenge, acknowledges Milkoreit. “We’re sending a critical new message: ‘What you currently have is insufficient.’ We recognize that this comes after four decades of efforts and struggles, encountering numerous political factors, and it’s clear that the climate work itself is becoming more complex. Researchers face challenges in conveying this troubling news, journalists find it hard to relay the harsh realities, and decision-makers often encounter resistance to this information,” she emphasizes.
It is vital to maintain focus on these issues. She and her co-authors urge that this report incite individuals to engage with the challenges and consider what actions can be taken at the personal level to support these efforts, whether through more mindful consumer choices or advocating for the urgency of taking action now. “Even for a reader to have the courage to face these troubling realities is a form of labor, and I’d like to acknowledge that effort,” she concludes.
