Tipping points, feed-backs & social collapse: the late Australian super-scientist Will Steffen in his own voice. From Radio Ecoshock 2018, Hothouse Earth and Trajectories of the Earth System. From Ecoshock 2020, the risk of “societal collapse” as climate impacts mount. We need to listen until we really “hear it”. A best of the best replay, for a life well given.

Listen to or download this Radio Ecoshock show in CD Quality (57 MB) or Lo-Fi (14 MB)


The world has lost a great climate scientist. From Australian National University, Professor Will Steffen passed away, following his fight with cancer. Australian newspapers listed out Steffen’s leadership positions in that country, and his role directing global projects like the International Geosphere-Biosphere Programme, and the Stockholm Resilience Center. But the media did not cover Will’s fundamental new visions of how the climate on this planet actually works.

Steffen brought out the doom of Hothouse Earth, but also a possible shelf where the hotter world might rest. He worked with teams outlining planetary boundaries – not just tipping points, but the ways complex natural systems interact. He led the legendary 2018 paper “Trajectories of the Earth System in the Anthropocene”. Within a few days of publication in PNAS, this masterful study was downloaded over a quarter of a million times.

In 2020, as the pandemic set in, Will Steffen joined 250 scientists and experts to publish “A warning on climate and the risk of societal collapse”.

We owe him so much. We owe him the chance to explain it all in his own words, in two key Radio Ecoshock interviews. I listened to them again. Timeless. His work is deep and disturbing. His inner voice was brave and pure but not strident. Steffen sets the stage for events unfolding for the rest of our lives and beyond.

Will Steffen worked with some of the world’s leading climate scientists, and climate thinkers. Two years after the 2018 Trajectories paper, Steffen and many of those same scientists took a darker view. Lust for power and profits was already setting a course for disaster: social collapse. You can see it: fire after fire, never-before-seen floods and storms, weather gone off course for plants, animals, big changes in winds, ice, and ocean currents. Without drastic action, humanity could be battered beyond the tolerance of civilized systems, beyond recovery. Things can move very fast.

So they warned us, 250 scientists and experts. Will Steffen and I spoke again, this time in 2020.

Fellow Australian David Spratt has a full and fitting tribute to Will Steffen, just published at the Climate Code Red blog. The title is: “Will Steffen’s crucial climate ideas on ‘Hothouse Earth’, tipping cascades and non-linearity.” I highly recommend his article to grasp the Steffen’s essential ideas, and his science.

Also listen to an interview with David Spratt about Steffen’s work on Open Spotify (free)


As a rock-climber, Will Steffen took on the high mountains and dangerous ice fields. For his work on climate, Will received awards and death threats. He battled climate deniers and hostile media in Australia and around the world. Steffen the communicator drew great scientists together, developed crucial insights and tools, advised governments and never, to the very end, stopped trying.

Will Steffen was 75. He did not live to see the new climate – to “find out”. But in a way, he of all people, already knew.


Find the full blogs for each interview, with all the links here:


Posted on September 13, 2018


Listen to or download (or pass on!) my 28 minute interview with climate scientist Will Steffen in CD Quality or Lo-Fi


Planet Earth is hurtling toward a new hotter state. But how hot? Are there landing spots safe enough for a human civilization? We get a big step toward answers with new science published by the National Academy on August 6th. The title is: “Trajectories of the Earth System in the Anthropocene.” The full paper is available to the public free of charge.

The study’s Abstract begins:

We explore the risk that self-reinforcing feedbacks could push the Earth System toward a planetary threshold that, if crossed, could prevent stabilization of the climate at intermediate temperature rises and cause continued warming on a “Hothouse Earth” pathway even as human emissions are reduced.

Or watch my coverage of that paper with Will Steffen on Radio Ecoshock Youtube here.



Climate Collapse & The Plastic Plague

Posted on December 16, 2020

Professor Will Steffen speaks for hundreds of scientists and experts with a warning: global warming may drive societies to collapse.

Climate Collapse & The Plastic Plague


Download or listen to this 29 minute 2020 interview with Dr. Will Steffen in CD Quality or Lo-Fi



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Alex Smith
Radio Ecoshock