‘Tipping points’ experts issue urgent message to world leaders

World leaders must take “immediate, unprecedented action” to prevent devastating climate tipping points, experts say.

The Global Tipping Points Conference is taking place in Exeter this week, and almost 200 delegates have endorsed a statement calling for action from policymakers – especially leaders meeting at the COP30 climate summit in Brazil later this year.

With global warming expected to exceed 1.5C within a few years, the experts warn that billions of people are at risk from climate tipping points.

They write: “Already tropical coral reefs have crossed their tipping point and are experiencing unprecedented dieback, impairing the livelihoods of hundreds of millions who depend on them.”

And they warn that a cascade of further tipping points – including the collapse of crucial ocean currents and dieback of the Amazon rainforest – could follow.

Every fraction of a degree above 1.5°C matters. And every year of “overshoot” matters too.

The Brazilian Presidency of COP30 has repeatedly highlighted tipping points in its communications, and the new statement joins the COP organisers in calling on governments to help trigger positive tipping points in their societies and economies.

By doing this, they can rapidly cut greenhouse gas emissions, and protect and restore the ecosystems that provide critical life support systems.

Professor Tim Lenton, from the Global Systems Institute at the University of Exeter, said: “We need decisive policy and civil society action – this is imperative for human rights and planetary health, and it’s ultimately a matter of survival.”

Mike Barrett, WWF’s Chief Scientific Adviser, said: “The risks of global tipping points are real, and the consequences catastrophic. And if we wait until we are experiencing the impacts, then we will also know it is already too late to act. The good news is that we know what to do to avert this – not least restoring nature and transitioning energy and food systems. But the time to act is now. Later is already too late.

“Governments and businesses must rapidly align their policies and financial flows to limit global warming and halt the destruction of nature to minimise the risk of triggering further dangerous tipping points. Instead, we must catalyse positive tipping points, especially in restoring nature which is one of our major allies in tacking climate change.” 

Full statement:

Global warming is projected to exceed 1.5°C within a few years, placing humanity in the danger zone where multiple climate tipping points pose catastrophic risks to billions of people. Already tropical coral reefs have crossed their tipping point and are experiencing unprecedented dieback, impairing the livelihoods of hundreds of millions who depend on them. Current warming has activated these irreversible changes and every fraction of additional warming dramatically increases the risk of triggering further damaging tipping points.

These include a collapse of deep water formation in the Labrador-Irminger Seas triggering abrupt climate changes that reduce food and water security in northwest Europe and West Africa. Particularly alarming is the risk of collapse of the Atlantic Meridional Overturning Circulation (AMOC), which would plunge northwest Europe into prolonged severe winters, while radically undermining global food and water security. The Amazon rainforest is also at risk of widespread dieback from the combined effects of climate change and deforestation.

The window for preventing these cascading climate dynamics is rapidly closing, demanding immediate, unprecedented action from policymakers worldwide, and especially from leaders at COP30. This is a human rights and planetary health imperative and ultimately a matter of survival.

Critical to preventing climate tipping points is minimizing both the magnitude and duration of temperature overshoot above 1.5°C. Every year and every fraction of a degree above 1.5°C matters. To minimize overshoot, global greenhouse gas emissions must be halved by 2030 compared to 2010 levels, requiring an unprecedented acceleration in decarbonisation. Only that way can the world reach net zero emissions in time to peak global temperatures well below 2°C and start returning back to, and then below, 1.5°C. This will also require scaling of sustainable carbon removal from the atmosphere.

Current Nationally Determined Contributions (NDCs) and binding long-term targets will only limit global warming to around 2.1°C. We therefore call on all nations updating their NDCs for the September 2025 deadline to set targets consistent with minimising overshoot of 1.5°C.

To achieve such targets we join the COP30 Presidency in calling on governments to enact policies that help trigger positive tipping points in their economies and societies, which generate self-propelling change in technologies and behaviours towards zero emissions. We also support the Global Mutirão initiative to catalyse collective action from civil society to help trigger positive tipping points to achieve common climate goals.

To trigger positive tipping points that help eliminate the 75% of greenhouse gas emissions linked to the energy system, and transition away from fossil fuels in a just, orderly, and equitable manner, we call on policymakers to adopt (and enforce) ambitious policy mandates to phase in clean technologies and phase out fossil fuelled ones. These include bans on the future sale of petrol/diesel cars, diesel trucks, and gas boilers. For less mature technologies such as green hydrogen, green ammonia and green steel, we call for increased investment in research, development and deployment.

To trigger positive tipping points that help eliminate the 25% of greenhouse gas emissions linked to food, farming, and deforestation, we call on policymakers to adopt trade policies that catalyse sustainable commodity production and to shift public money from the livestock sector to plant-based proteins. This will also help limit the risk of tipping points in the biosphere – including dieback of the Amazon rainforest – and can liberate land for regenerating nature.

To trigger positive tipping points of nature regeneration that scale up sustainable removal of CO2 from the atmosphere, we call for policy and civil society action to protect indigenous rights, support community-led conservation initiatives, and ensure fair and transparent valuing of nature. This will help achieve the Kunming-Montreal Global Biodiversity Framework targets to restore 30% of degraded ecosystems and conserve 30% of land, waters and seas. It is essential to limiting overshoot of 1.5°C.

Only with such decisive policy and civil society action can the world tip its trajectory from facing unmanageable climate tipping point risks to seizing positive tipping point opportunities.