A Voice for Our Time: Remembering Earth Systems Scientist, Will Steffen

Earlier this year, one of the world’s most important cultural leaders passed away at the age of 75 after an extended battle with cancer.

Will Steffen was a pioneer in climate research and was one of the initiators of and a leading voice for Earth Systems Science, which looks at our world holistically and examines the interaction of our planet’s natural systems: solar cycles; atmospheric chemistry, and weather dynamics, the water cycles, ocean, and terrestrial nutrient cycling, and so on.

Steffen’s academic career began in the US, where he acquired a Ph.D. in chemical engineering at the University of Missouri. He then migrated to Australia to take up the field of x-ray crystallography at the Australia National University in Canberra, where he was based for his entire career.

Steffen’s academic focus evolved into an interdisciplinary approach to big scientific questions. He recognized that our planet’s natural systems were being profoundly impacted by human activity. Steffen was a lead author of a groundbreaking paper published in 2009 by Nature titled, A Safe Operating Space for Humanity. It defined a framework for how to think about safe boundaries for Earth’s interactive systems.

From 1998 to 2004, Steffen served as Executive Director of the International Geosphere-Biosphere Program, where he led a broad, interdisciplinary effort to understand and quantify our Earth’s interactive system dynamics. He was a contributor to five Intergovernmental Panel on Climate Change (IPCC) reports and had a massive impact on understanding climate change and the interactive dynamics of the Earth’s systems and their impact on human survival.

Besides being a brilliant scientist and synthesist, Steffen was also a gifted communicator, with the skill of speaking plainly and clearly about immensely complex issues. Audiences were enthralled by his clear, inspiring explanation of the effects we are having on our world – and what it means for us all.

During the time Will Steffen was battling cancer, he remained a powerful public voice, taking every opportunity to share his deep concern about the escalating human imprint on our Earth’s destabilized natural systems.

Steffen’s understanding and wisdom are reflected in two different MAHB Dialogues we shared with him in recent years. His own words, taken from our time with him, are the best testament to Will Steffen’s enduring impact on life on Earth.

Steffen said this about the human impact on our Earth’s natural systems…

“The best way to look at this is to look at the phenomenon we call the Great Acceleration. If you go back a hundred years, things were changing. We were in the industrial era. We were using fossil fuels. We were clearing land. But somewhere around the mid-20th century, we really took off. We call this the Great Acceleration, and you can see it in all sorts of parameters. You can see it in population. You can see it in economic activity. You can see it in energy use. You can certainly see it in the global environment. You can see it in the rapid accumulation of greenhouse gases post-1950, as temperatures started moving upward.”

Steffen explained why the global human footprint in recent decades has become so troubling:

“It was only in the mid-20th century that we really started banging into the operating limits of our global environment. More recently, of course, these things are accelerating in very many different ways. I would say in the last 10 or 20 years, probably one of the most dramatic increases we’ve seen is in things that we call novel entities: new stuff that we are throwing into the Earth System; think of plastics, and a plethora of man-made chemicals. You can think of electromagnetic radiation associated with the digital world, with repeater stations everywhere around the world now. This Great Acceleration is changing in character a bit, but there is no sign that it is slowing down.”

Steffen had this to say about exceeding safe operating limits on climate change, and the accelerating loss of biodiversity on Earth:

“The concentration of carbon dioxide in the atmosphere, for which we placed the boundary at 350 parts per million, is now rising at two or three parts per million per year, which is enormously fast. Right now, we’re sitting at somewhere around 418 to 420 parts per million, way outside the acceptable boundary. The same thing with biosphere integrity, what we’re seeing in the rate of biodiversity loss is that it is again actually increasing. Recent estimates are somewhere around perhaps 100 times faster than background levels. Some people are estimating 1000 times the background levels. Our sustainable boundary for that is only 10 times background levels, or even a bit less…Now, up to 30 or 40% of the entire productivity of the terrestrial biosphere… is now being harvested or co-opted by humans; way above the limit we think is appropriate for a sustainable Earth system.”

On the human way of relating to the natural world, Steffen had this to say:

“We have developed cultures and societies, particularly since the Industrial Revolution, that are increasingly disengaged or disconnected from nature, or from what we say is the rest of the Earth System. Unfortunately, this means we think we can operate independently from the Earth; that we can just leave a few remnants in terms of national parks; that our economies can operate without limits, with the rest of the Earth viewed mainly as resources, simply to be exploited. What we’re seeing now clearly is that there are limits, what we call planetary boundaries. We have to change fundamentally how we view our place in the natural world.”

Steffen said this about our human capacity to get past our cultural overreach:

“When you look at a map of the world, what you see is a bunch of different colors with lines around them that identify nation-states. But when you get up in space, like an astronaut, you don’t see that. You see this beautiful blue marble. You see a single system… Our natural Earth-scale systems don’t recognize or respond to national boundaries. They act together to form a single Earth system. So, the hope is that if we change the way we think, the fact that we live in nation-states, but we share one life support system, and we have now as humans become so numerous and so technologically powerful, we are seriously damaging our own life support system…My hope is that we can reach a social tipping point, where we change the way we view ourselves, the way we view our relationship with each other, and the way we view our relationship to our planetary home, the Earth system. We’ve got to get past our tribalism. That’s something that’s plagued us in the past. There is no room anymore for that.”

Steffen also offered this advice on how to live as a concerned Earth citizen:

“There are multiple pressure points on failing economic systems and we’re starting to see a lot of those pressure points being highlighted. My advice to individuals is, do whatever you are comfortable doing… find ways to apply pressure to save precious areas of ecosystems or to stop other damaging activities. Systems are made up of large groups of people. We need to understand where the pressure points are. We need to apply grassroots pressure from the bottom up to get our Earth System to operate in a more sustainable direction.”

Will Steffen was not a household name. Just the same, a thousand years from now, he will be celebrated as a 21st-century leader in alerting humanity to the growing threats to our planet’s critical living systems. In the years ahead, Steffen’s academic legacy will have even more of an impact in moving humanity in a life-affirming, sustainable direction. In sum, we can say of Will Steffen that his was a life well lived.

Paul R Ehrlich, Julian Cribb, Geoffrey Holland