Timothy Lenton is a professor of climate change and Earth system science at the University of Exeter. He started working on tipping points in the 1990s, making him one of the first scientists in the world to study this form of planetary risk. In an upcoming book, Positive Tipping Points: How to Fix the Climate Crisis, he argues the Earth has entered an “unstable period” but humanity can still prevail if we can trigger positive social and economic tipping points to reverse the damage that has already been done. On 30 June, he will host a global conference on tipping points.
How do you define a tipping point?
A tipping point is where change becomes self-propelling within a system, meaning it will shift from one state to another. That can happen because the balance of feedback in the system switches from damping feedback to amplifying feedback. The result can look very rapid and irreversible.
How has our understanding of these risks changed?
We first published a map of climate tipping elements in 2008, Since then, we have added much more than we have subtracted from that map. And, unfortunately, in the intervening 17 years, the evidence suggests we’re much closer to some of these tipping points than we thought.
