Among the many theories about how planet Earth works, none are more fascinating than the role of complexity – the idea that, as human societies develop, they get increasingly complicated; tied together and dependent on connections and systems that defy comprehension, that endlessly proliferate and are liable to come undone, in self-amplifying cascades.

Thomas Homer-Dixon has devoted his academic career to studying complex systems, and how they break bad. Pernicious and virtuous cascades interest him greatly.

Homer-Dixon is the founder and Executive Director of the Cascade Institute at Royal Roads University in Victoria, British Columbia. Through the complexity lens, Homer-Dixon studies social, economic and ecological instability, and how people and societies can thwart threats and promote virtuous cascades.

He’s written various books: The Upside of Down, Environment, Scarcity and Violence and The Ingenuity Gap, and, his most recent — Commanding Hope; The Power We Have to Renew a World in Peril.

Listen to our conversation in today’ podcast. Click on the play button above, or go here.

Human emission of CO2 and other greenhouse gases has warmed Earth’s surface temperature by about 1.1 degrees, relative to the late 19th century, at a rate of about three tenths of a degree per decade since 1980.

That rate is steadily rising.

As Earth’s surface warms, thermal expansion and melting ice sheets have raised sea levels by two tenths of a meter.

That rate is rising too.

Slow and steady for years to come? Think again.

In a 2023 report, a team of scientists warned about tipping points — inflection points where Earth warming and the destruction of Earth’s living fabric become non-linear and unstoppable, and where Earth systems start shifting to new, potentially dangerous states.

Twenty-five tipping points were identified. Five major ones may already have been transgressed. More could soon be tripped, the report’s authors warned, triggering a cascade of amplifying feedbacks across Earth’s interlocked climate system and biosphere.

Globalized human economies and societies will inevitably suffer.

As if all this weren’t scary enough, “there is no adequate global governance at the scale of the threats posed by negative tipping points,” the report’s authors warned. Manjana Milkoreit was one of them. Milkoreit is a postdoctoral researcher at the University of Oslo, and lead author of a chapter of the report about tipping point governance.

Listen to our conversation in today’ podcast. Click on the play button above, or go here.