Warm-water coral reefs near collapse, larger irreversible threats looming: Report

Researchers for a recent climate survey have warned that without urgent global action to curb warming, the world is heading toward far more destructive and irreversible crises.

The findings come from the "Second Global Tipping Points Report", by the University of Exeter in the United Kingdom and its global partners published on Monday (13 October).

The assessment noted that humanity has entered a "new reality" after the world reached the first major climate tipping point.

The report states that warm-water coral reefs are now collapsing at an accelerating rate due to rising sea temperatures. Nearly one billion people depend directly or indirectly on these ecosystems for their livelihoods, while reefs support around 25% of all marine species. 

Scientists caution that without drastic reductions in global warming, most coral ecosystems will disappear entirely, with only small pockets surviving.

The warning comes as global temperatures edge closer to the 1.5°C threshold. Researchers say further tipping points could soon be triggered — including the collapse of the Amazon rainforest, the melting of polar ice sheets, and the breakdown of the Atlantic Meridional Overturning Circulation (AMOC), a crucial ocean current. 

These impacts would lead to more frequent natural disasters, food insecurity, and widespread humanitarian crises, the report states.

The report brings together the work of 160 scientists from 87 institutions across 23 countries. It warns that even fractional increases in temperature beyond 1.5°C could rapidly escalate planetary risk.

Released ahead of the COP30 climate summit in Brazil this November, the report calls for immediate action to prevent further overshoot. 

Researchers argue that triggering "positive tipping points" — such as rapid adoption of renewable energy — is essential to avoid irreversible damage.

Professor Tim Lenton of the University of Exeter said, "We are moving dangerously close to multiple tipping points. Without unprecedented global action now, both humanity and nature will face terrifying consequences."

Dr. Mike Barrett, chief scientific adviser at WWF-UK and a co-author of the report, said, "The collapse of warm-water coral reefs is a severe disaster for nature and people. If we fail to act now, we will also lose the Amazon, the ice sheets and the ocean currents."

The report also finds that existing global governance frameworks are not designed to respond to sudden or long-term climate catastrophes. 

Scientists are calling for rapid emissions cuts, large-scale carbon removal, and the integration of tipping-point risks into adaptation, legal, and loss-and-damage frameworks.

Dr Manjana Milkoreit of the University of Oslo said, "To avoid tipping points, we must adopt strong mitigation strategies from the outset, so that the time spent beyond temperature limits remains minimal."

The Brazilian COP30 presidency has launched the "Global Mutirão" initiative to mobilize multiple sectors in climate action. 

Ambassador André Corrêa do Lago, president-designate of COP30, welcomed the report, calling it "realistic and hopeful evidence that humanity can still choose a different path."

The report also points to signs of progress. Solar and wind power are expanding rapidly worldwide, while electric vehicles, batteries and heat pumps are scaling up at record pace. 

Scientists highlight "super-leverage points," where action in one sector can accelerate change in others — transforming energy, transport and industry simultaneously.

Brazil is positioned to lead new positive tipping points in emerging industries such as green hydrogen, green steel and green ammonia. Ecosystem restoration and supply-chain reform are also identified as key pathways to sustainable land and food systems.

Public sentiment is shifting, too, with climate awareness growing globally and small movements increasingly catalyzing large-scale change.

Professor Lenton concluded, "Without a collective pathway that combines policy and civic action, we will neither avoid existential tipping point risks nor seize the opportunities for positive transformation."