Alex Steffen

photo of a man fanning the pages of a book

On the list of best job titles ever – explorer, inventor, superstar architect – “planetary futurist” must surely be near the top of the pile. Writer Alex Steffen has earned that enviable moniker through more than a decade of long, hard thinking about what it will take to accommodate some 9 billion people on a finite planet. Steffen first distinguished himself as the founder and executive editor of With more than 12,000 articles dedicated to sustainability, WorldChanging (later published as a physical book) was a kind of digital encyclopedia focused on imagining the details of a “bright green future,” a term coined by Steffen.

His latest book, Carbon Zero, lasers in on a longtime preoccupation of Steffen’s: the ecological necessity of redesigning and rebuilding our cities to reduce our resource consumption. In the book he writes: “How we build our cities will decide, more than any other factor, how much we heat the planet.” Environmentally minded urban renewal will also, Steffen argues, lead to a “vast 40-year boom” that will make us all more prosperous.

Steffen stopped by the Earth Island offices in January to discuss his ideas. In person he is animated without being overwrought. When considering a question his gaze sometimes fades into a thousand-yard stare, evidence of the wheels churning away in his head. The result is usually bracing and soundbite-ready. As he told me in response to a question about the meme of the Anthropocene: “Being the largest force of change and being in control are profoundly different things.”

You’ve been writing about sustainability for a long while. Was there anything in the course of researching and writing Carbon Zero that surprised you?

I think the biggest idea whose implications I had not really wrestled with was simply the idea of zero. We know we live on a finite planet. We know that the systems that make up the natural world of this planet are themselves finite and can only withstand certain amounts of change, which means that we know there is an amount of pressure beyond which we should not go. So, for example, on climate we already know that we probably should have topped out at about 350 [parts per million of CO2 in the atmosphere], and that we definitely need to keep it under 450 to 500 parts per million. And in order to do that, we are going to need to stop emitting net greenhouse gases – to stop contributing to climate change completely. On some theoretical level I knew that and I think many of us know that. But the full implication of needing to turn society towards zero impact worldwide in just a few decades – and that being a very pressing task with serious consequences of failure – that had not sunk in, honestly. I think once you start to think about zero as the target it really changes what sounds realistic or not.

The environmentalism of the 1960s and 1970s was all going about back-to-the-land. Your prescription is that we have to go back-to-the-cities. Can you talk about that?

Environmentalism developed during the Industrial Revolution, and a way of looking at the world was juxtaposing a traditional, rural lifestyle and an industrial, urban lifestyle. And when comparing those two, it’s pretty clear that the traditional lifestyle had many sustainability benefits in comparison. So environmentalism as a whole took on a sort of pro-rural, pro-back-to-the-land, anti-industrial, anti-urban standpoint – which made total sense in its emergence. But since then we have come to realize that the rural is no longer what it was. It’s transforming so quickly everywhere that people who live in the countryside are using industrial systems to farm and forest and fish, and are increasingly connected to urban expectations about consumption and access to resources and education and so forth. That trend is only going to accelerate. We are increasingly an urban species – already half of humanity lives in cities. By the middle of the century, something more like 70 percent will live in cities, but something more akin to 95 percent will live within a day’s travel of a city. And we know that when people have access to cities they start acting much more like urban people than like traditional rural people. That being the case, we have to figure out how to make cities work better environmentally. During the last 15 years a lot of people who have been working on the future of cities have come to understand that it is possible that cities are the best tool to get us to a zero impact way of living.

That’s a pretty big task, redesigning cities. How quickly can that be done? Won’t we run into the temporal constraint of only having a finite amount of time to make these changes?

In the best-case scenario, this is an extremely daunting challenge. That said, it’s really important that we – those of us who care about the planet – begin to have a more strategic conversation of the meaning of “realism.” In the last 30 years, people who very much want to avoid change, who are invested heavily in the status quo —oil companies, coal companies, car companies, et cetera – have put literally billions of dollars into trying to define, especially in America, what realism means. And so it has come to the point where even those of us who understand that on a planetary scale the only realistic action is drastic, often, when we are discussing policy or social change, we tend to default to this other sense of realism. Which is sort of like, ‘How far can the status quo change?’” A status quo that has been heavily, heavily influenced by people who don’t want it to change at all. We need to reclaim the meaning of realism, because destroying the planet is not realistic.

In Carbon Zero you write, in what sounded to me like an echo of Buckminster Fuller, “When there’s no new solution available, business as usual is a given.” The technological solutions are off-the-shelf and shovel-ready. But we’ve got this political logjam. So how do you break through and redefine realism?

Yes, if our intention is to create the required amount of change in the available amount of time, we have to start from the presumption that there will be winners and losers in the political fight. Which means frankly that many people who are heavily invested in the status quo – who tend to be very wealthy, powerful people – are going to lose big. The other side of the coin is that a great many people who are currently set to lose a lot will gain a lot instead. I think we need to be ready to have that fight and acknowledge that things cannot simply be kept the way they are. The systems that comprise contemporary life, especially contemporary American life, are unsustainable and they will not continue. The writing is already on the wall. So we need to have a politics and a civic culture that simply starts from the presumption that staying the same is not an option. Once we go there, I think it’s possible to point to all the ways in which benefits can accrue for the vast majority of people. And at that point, I think, presented with the option of avoiding planetary catastrophe and improving their cities, communities, and lives, most people will be ready to support pretty strong action.

So getting to carbon zero is a bit of a zero sum game. Some people are going to win; some people are going to lose.


I thought one of the best lines in the book was: “Sprawl, malls, and highways don’t have the last word in prosperity.” You sketch a pretty compelling picture of a bright green future. But our assumptions about what is “normal” are pretty hard to shake.

This is a complex set of questions. There are things in here about primates and the way we think. There are things in here that are about politics and the politics we have inherited. And there are things in here that are just sort of about the moment we’re in. First of all, people have the tendency to underestimate the amount of change that they will go through, and overestimate the importance of the change that they have gone through. So we have the tendency to just assume that things in the future will be kind of like how they are now. That is a pretty universal problem with people. We also have a very difficult time understanding things that we can’t fully imagine. And we in the environmental movement and the sustainability movement have not done a good enough job at helping people imagine what could be different. Added to that, there is this whole political force. I would argue that the climate denialism and anti-sustainability component of our politics is the best organized and the best funded part of our civic world. It definitely blows out of the water everything environmentalists have ever done put together, and they’re winning. So I think it’s very important not to downplay the degree to which we don’t talk about something being different simply because there’s so much money and energy being spent attacking anybody who suggests that they should be different.

If you take some of your conclusions to their logical extension, it could mean abandoning some parts of our built environments. Do I have that right? Are we just going to evacuate, say, suburban Phoenix?

I think we’re absolutely in profound denial about the magnitude of the pressures that are weighing on us, especially outer ring suburbia and exurban sprawl. The simple fact is that those places are not sustainable financially, which is why you have, for example, counties all over the Midwest that are starting to grind up their asphalt roads because the insurance standards are lower on gravel roads. All over the country, you have literally millions of homes that are abandoned.

These are the examples of existing systems that are crumbling and unsustainably expensive.

Yeah. You know, there’s a reason why the cities are going bankrupt, or are going into receivership with the state, or are needing the emergency bailouts – they are all exurban cities. And there’s for reason for that: When you spread things out and then you service them with lot of infrastructure that is stretching a long way, that’s an incredibly expensive thing to undertake. But just on its own terms, when you add the pressures of rising energy costs, climate change, the need to take into account pollution externalities and other things like that – when you take into account the real functioning of that, they become totally untenable. It’s a real abdication of responsibility that none of the people in American leadership are even addressing. We’re really far along the curve already, and many Americans are going to be profoundly just deeply surprised by how unsustainable the places we have taken for granted are. And when you add on top of that climate impacts and the extent to which places that are spread out are more vulnerable to disruption – they’re more brittle – and when you add to that the fact that much of the exurban sprawl in America has happened in the Sunbelt, and those are places that are going to become more difficult to live in just the next few years. They already are more difficult to live than they were. Water is going to be more and more of a problem, et cetera, et cetera. I think we are really facing a crisis there, and I do not know of any way that those places can be saved as they are. I do not know of any way that extremely spread out exurban, auto-dependent sprawl can be made financially and ecologically sustainable.

Do you think the real estate and financial meltdown was a kind of id-level market correction in which some people realized that the value is just not there?

Well, yeah. I think that the financial crisis was caused not by people wanting homes and taking out bad loans, but by banks structuring bad loans that they could get people to take for houses. There were a lot of houses built out on the fringe that there was no market for. The only reason why anybody would buy there was simply because people were desperate to get into real estate and there were loans that would let you buy a house with no money down and basically bad credit. And so people bought homes they could not afford in places that shouldn’t have been built in the first place. So I do think that some of that is just a natural corrective to what basically was kind of a Ponzi scheme. But on top of that, you also have this larger societal shift where younger people in great numbers are preferring to live in cities. And frankly, if it were more affordable to live in cities, even more younger people would be. The limit to the number of people who are under 40 living in cities is largely defined by how unaffordable those cities are, because we’ve built so little housing in the last couple of decades in them. I like to use the line that younger people are not so much looking for dream homes anymore as dream neighborhoods. There has been this pretty profound shift in which people want a certain kind of life that is simply not providable by the exurbs. So it’s a big challenge. I don’t take any pleasure in that conundrum because I know that means a lot of people who didn’t mean to put themselves in that situation are going to be hard hit by it, and that’s where I think there’s a failure of leadership in that, really, our national leaders should be preparing for that and trying to save which places we can.

Recognizing that these prescriptions are connected, and that you’re doing network and systems thinking, what are your top three or four prescriptions?

Build, build, build – and make it walkable. The single strongest finding in urban planning these days is that the denser a community is, the less transportation energy and the few transportation emissions a community produces. We have since found that are is really strong evidence that denser communities – if they are made walkable – drop even farther in their emissions, but also that emissions in other and apparently unrelated areas drop as well. For example, people consume fewer products. Some of this makes sense, right? If you live in an apartment you probably don’t own a home gym. It means less stuff, and more shared stuff, more access to services rather buying products. In most American cities, the biggest job is to densify quickly enough so that people can live without cars. And that involves building a certain level of density, at least on main corridors and commercial areas and providing that density with transit and bike lanes and good pedestrian amenities so that people actually want to be walking.

It did strike me in reading Carbon Zero that there’s a lot of normative statements in there. What do you say to the person who is of an older generation, accustomed to life as it is, and just says, “I prefer a six lane divided street. I like being in the car, going from one air conditioned space to another”?

My answer there generally is: If someone is truly willing to pay for all of that – including the climate impacts of that, offsetting that, buying better technology to do those things in a more sustainable fashion – if somebody is actually genuinely willing to do that, I’m like, “Okay, great, to each his or her own.” But the fact of the matter is that nobody is willing to pay to do that. They all want essentially socialized consequences. For the vast majority of people who live in the exurbs it would be prohibitively expensive to pay for the true cost of their lifestyle.

This interview is going to appear in a special edition we’re doing around the new meme of the Anthropocene. I read somewhere that you don’t like that word. Why not?

I think it’s really important to separate the scientific Anthropocene – is which the description of the simple fact that when people look back millennia from now, there will be an observable strata, an observable layer of human impacts from this time —from the metaphoric Anthropocene, which is the idea that because we are the largest force of change on the planet, we actually control the planet. Being the largest force of change and being in control are profoundly different things. A lot of the “post-environmentalists” are in this camp, a lot of the geoengineers are in this camp, where people are basically saying, to quote that Whole Earth Catalog line, “We are as gods and might as well get good at it.” But the fact is that we are not as gods. We are much, much better at destroying and destabilizing than we are at creating and healing.

We are setting in motion things the consequences of which are much larger than the actual actions we took to disturb them. We do not have the capacity to even catch up to those disruptive effects, much less have the wisdom and mastery to remake it if we did. So the biggest problem I have with the Anthropocene is that a lot of people use it to mean that this is the time now that humans decide what happens on the planet. And that is only true to the extent that we decide how to rein in our own stupidity. We are most definitely not in charge. There’s that old line, “nature bats last.” The batting order hasn’t changed just because we’ve come up with the term Anthropocene.

Jason Mark is editor of Earth Island Journal. This interview has been edited for clarity and length.

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