Rate‑Induced Tipping Points: The Compost‑Bomb Instability

Sudden changes in the state of the system, known as "tipping points" or "critical transitions", are often associated with a "critical level" of external conditions at which stable state disappears or destabilises in a bifurcation, causing the system to move to another state. However, recent mathematical work highlighted that some systems simply do not have any critical levels, but they do have "critical rates" of change. Above a critical rate the system is unable to keep pace with continuously changing external conditions and `tips' to another state. This happens even though there is no obvious loss of stability---the stable state continuous to exist for all fixed levels of external conditions!

This talk describes mathematical framework, beyond traditional bifurcation theory, required to understand the importance of "how quickly external conditions change" in natural systems. In particular, it explains the curious "compost-bomb instability" --- an explosive release of soil carbon from peatlands into the atmosphere above some critical rate of global warming. Furthermore, it discusses the relevance of rate-induced tipping for the current and future climate epoch that is not so much about the ultimate magnitude of warmth but its rate of change.