‘If We Wait, It Will Be Too Late’, 600 Scientists Warn, as Climate Tipping Points Approach

A group of nearly 600 scientists is declaring yet again that “the planet’s future hangs in the balance,” and “which way it tips is down to our actions now and in the years to come.”

With global warming soon to exceed the Paris agreement target of 1.5°C average global warming, “the world has entered a new reality,” warns the Dartington Declaration, led by climate scientist Tim Lenton of the University of Exeter Global Systems Institute and issued Dec. 1. “This puts humanity in the danger zone where multiple climate tipping points pose devastating risks to billions of people,” and “every fraction of a degree of additional warming increases the risk of triggering further damaging tipping points.”

As examples of the approaching risks, the declaration cites:

• Warm-water coral reefs “experiencing unprecedented mortality” as they cross their thermal tipping point, threatening the livelihoods of hundreds of millions of people;

• Melting polar ice sheets on the verge of locking in long-term sea level rise that will affect hundreds of millions of others;

• The potential collapse of the Atlantic Meridional Overturning Circulation, plunging northwest Europe into “prolonged severe winters” and undermining global food and water security;

• A widespread dieback of the Amazon, brought out by a combination of climate change and deforestation.

“These climate tipping point risks are interconnected, and most of the interactions between them are destabilizing, meaning tipping one system makes tipping another more likely,” the declaration states. “How hot we let it get and for how long really matters in preventing climate tipping points.”

So “the magnitude and duration of global temperature overshoot above 1.5°C has to be minimized—and ultimately global warming will need to be reduced towards 1°C.”

The most important next steps, the scientists say, are an “unprecedented acceleration” of a global fossil fuel phaseout, rapid reduction in emissions of methane and other short-lived but very potent climate pollutants, and sustainable removable of atmospheric carbon, “especially through the protection and restoration of forests and other natural carbon sinks.”

With the window for preventing these tipping points rapidly closing, “the only credible risk management strategy is to act in advance,” the declaration warns. “If we wait, it will be too late.”