Circular Metabolism
Circular Metabolism Podcast
The most important yet misunderstood concept in climate science - Tim Lenton

The most important yet misunderstood concept in climate science - Tim Lenton

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There is an essential and yet poorly understood concept in climate science: tipping points.

Several climate tipping points (such as the ice loss in Greenland and Antarctica or the slowdown of the Atlantic circulation) are dangerously close and run the risk of triggering a "tipping cascade".

To understand these risks and know how to keep us in a safe space through positive tipping points, we are talking with Professor Tim Lenton. Tim Lenton is Chair in Climate Change and Earth System Science at the University of Exeter.


  • 00:00 Introduction

  • 05:33 The Earth system

  • 11:18 Vital signs of the system

  • 15:28 Tipping points

  • 29:00 Irreversibility

  • 32:34 Civilizational tipping points

  • 35:08 Early warning signals

  • 38:31 Socio-ecological tipping points

  • 44:19 Positive tipping points


Recommended books:

  • Gaia, a new look at life on earth (1979) James Lovelock

  • The Ages of Gaia (1988), James Lovelock

Scientific articles:

  • Lenton's tipping points article :

  • Planetary boundaries:

  • Social tipping points (the "25% rule"):


• Map of the tipping elements:

2 main views:

  • Object (thing) perspective: seeing the system's elements as static and well defined

  • Process perspective: seeing the system's elements as changing and interconnected

Types of feedback loops:

  • Damping feedback (provides stability)

  • Amplifying feedback (creates possible instability)

Types of cycles:

  • Real cycles made of material flows

  • Causal cycles made of causal chains between events

Tipping point:

  • Threshold of an amplifying feedback loop beyond which change becomes self-propelling

  • Happens when the damping feedbacks get weaker than the amplifying feedbacks (variability increases)


1 commentaire
Circular Metabolism
Circular Metabolism Podcast
👋Bonjour et Bienvenu.e au Circular Metabolism Podcast. Le rendez vous bi-hebdomadaire qui interviewe des chercheurs, des décideurs politiques et des praticiens pour mieux comprendre le métabolisme de nos villes et comment réduire leur impact environnemental d’une manière systémique, juste et contextualisée. Ce podcast est produit par Aristide Athanassiadis membre et co-fondateur de Metabolism of Cities.