Interview with author Peter Kalmus

We recently spoke with Peter Kalmus, PhD, a climate scientist at NASA’s Jet Propulsion Lab. Kalmus studies clouds and climate change for NASA, and he’s an advocate for the environment in his personal life as well. For example, over the past several years, Kalmus has reduced his greenhouse gas emissions from 23 tonnes—which is roughly the American average—to two tonnes.

A large part of Kalmus’ dramatic CO2 reduction was the result of eliminating travel by plane, since, he wrote in 2016, that “Hour for hour, there’s no better way to warm the planet than to fly in a plane.” Not only does one international flight emit 10 times what an average Kenyan emits in a year, but he says that planes emit nitrogen oxides into the upper troposphere, form contrails, and seed cirrus clouds with aerosols from fuel combustion, all of which compound, by at least double, the warming effects.

(Editor’s note: Currently, no viable non-fossil fuel option exists for normal commercial travel; therefore, changing our flying habits is our only option in limiting air travel’s enormous carbon outlay.)

Kalmus has also turned his back (and front) yard into a vegetable garden; his family keeps chickens and bees; and they compost. He also runs his car on vegetable oil, and commutes to his job by bike day.

He is also a long-time Vipassana meditator, who sees the practice as essential in the climate crisis, which, he writes on his website, ‘is intertwined deeply with our lives, physically, socially, and spiritually.”  He sees that our climate predicament has “deep roots in our society, our structures of thinking and belief, and the ways we relate to the biosphere, each other, and ourselves.”

You can read more in his book,  Being the Change: Live Well and Spark a Climate RevolutionHe speaks here on his own behalf.

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Question: Tell us a bit about your background, and how you came to be involved with climate science?

Peter Kalmus:

I came to climate change really late. In fact, it wasn’t until 2006 that I got concerned about it. I was at Columbia University then, working on my doctorate in astrophysics.  I was dealing with the ‘big’ questions of life, for example, Where did the universe come from?’

But then [NASA scientist and environmental activist] Jim Hansen came to speak at our physics class. Hansen spoke about the energy imbalance on the planet. I saw the implications right away.

I was really amazed that the rest of the room didn’t seem to react. But, then, I had been oblivious before too. But this also was the year the movie An Inconvenient Truth came out, and my first son had also just been born, which shifted my perspective to the long-term.

After Hanson’s lecture, I wanted to talk about climate change, but nobody seemed to want to talk with me about it. My wife would talk about it with me, and my dad would talk about it with me, but he was a skeptic. He was trying to explain to me why there wasn’t evidence of global warming.

I did find one undergraduate who was interested, and together we tried to pressure Columbia University into paying a little extra for renewable energy. It was like talking to a brick wall. We tried to engage the undergraduate environmental groups. They were not interested at all. They were working on campaigns such as getting cloth bags in the dining hall. Each saw his or her pet campaign as the most important thing.

This experience changed my perspective on work, too. I eventually couldn’t sustain thinking about my astrophysics. I was fiddling while Rome was burning. It’s hard to do normal stuff while you are worried about climate change.

Question: You’ve made a significant number of lifestyle changes, including growing your own food, biking to work, and giving up traveling by plane. Was there a turning point for you in making these changes?

PK: Running the numbers.

I looked at my emission profile, and flying was by far my biggest emission; electricity was lowest. Before I ran the numbers, I was ready to spend more than I could afford on solar panels, and I wouldn’t have changed my flying.

It helped me understand and prioritize my options, which is a critical step if you want to take action. In my opinion, talking about reducing your emissions without running your numbers is like traveling without a map. It dawned on me that I was trying to talk to others about moving away from fossil fuel, when I could simply move away from it myself.

This also gave me an opportunity to deal with my frustration with inaction. Shaking people by the lapels was just pissing them off. So I decided to explore what it’s like to live with less fossil fuel.

Making changes wasn’t what I expected! It turned out that it wasn’t about the sacrifices, but rather it was fun, and a bit subversive. For example, I converted my car to run on vegetable oil, which is technically illegal since we are all taxed for the roads each time we purchase gas.

And when I moved to California for work in 2008, one of the very first changes I made was riding my bike to work. This was another turning point for me. I just loved biking. It made me healthier and happier. Far from being a sacrifice, biking felt really liberating.

This became my perspective on change.


Question: What do we need to do right now as a culture to fight against climate change?


PK: The most important shift right now is to completely decarbonize the energy system. We are using fossil fuels because it’s easy. But it’s basically killing the planet, by which I mean the planetary systems human civilization depends on for life support.


We have to go to zero carbon. So the next step is electrifying as much as we can—cars, homes. The hardest stuff will be our agriculture system and aviation. In airplanes, you are constrained by materials; for example, batteries are really heavy.


Question: What keeps you up at night? 


PK: That the public isn’t waking up fast enough. We don’t need to know more science. We have everything we need to know. There is no reasonable doubt. That our problem just isn’t a physical problem, but it’s a human problem.

How many species are on this planet? We don’t even know—definitely millions, maybe way more. And we think we’re the smartest species, of all those millions. And yet we’re the only one messing up the biosphere for ALL the species. We have all these examples in the natural world of animals and other beings living perfectly happy lives without fossil fuels. We did too. It’s only been a couple of hundred years that we’ve been burning this stuff.

The only thing stopping us is our will.

Also, I also worry that it’s 2018, and it’s already so late. We’re already at 1.1 or 1.2 [degrees Celsius warmer], and something like another .5 is already baked into the system.

Even if we went cold turkey right now with burning fossil fuels–which we can’t do—we’d likely be above 1.5 C, and we still everyone is talking about limiting the increase to 1.5. This disconnect keeps me up at night. Really smart people are living in fantasy land.


Question: What about the idea that we can address this problem through technology?


PK: Our culture fetishizes technology entrepreneurship to an irresponsible extent. It’s completely intellectually lazy to say, ‘Something [technological] will take care of it.”  Or that ‘1.5 degrees is possible with negative emissions technology.’ That to me is equivalent to hoping for a climate change magical fixing spell.

Now I totally think we should be researching such technology–but we’re not even close [to having such technology]. And this technology may not be economically feasible even if we did have it.

A lot of this is about money. The whole reason we’re burning fossil fuel is because it’s great economically. Imagine you have a car, but instead of an engine you have 20 employees pushing you around. Or airplanes—our entire economy is based on fossil fuel. To put that economic genie back in the bottle we would have to reverse the money flow.

We have some really prominent climate scientists still talking about it, but few are warning us that [technology cure] is unrealistic. Because it’s politically expedient.


Question: What has to happen politically to enact change?


PK: We can’t have policies for climate change unless we have politicians who think they will lose their jobs if they don’t create these policies.

Right now, even politicians that care about climate change may think, ‘I better be incremental so I don’t get voted out.’ So we need to change that. We need to vote. We can’t expect the collective, rapid change that we need unless normal people vote on this. If there are ten issues voters care about—say, gun control, economy, immigration—if climate change is number ten, politicians won’t be held accountable. They know the polls, and they follow them. They have to.

The question is a psychological and social question: What will get people to actually move the environment from number-ten voting priority to number two? Or even number one?


Question: What is the worst case scenario, do you think?


PK: The worst….well, everything depends on humans, so it’s hard to predict.

I personally think that humans are like cockroaches: we won’t go extinct. I’ve never seen any evidence for human extinction. Somehow it seems as though people either imagine a future like Star Trek, or they imagine no humans at all.

However, it seems as though we can’t imagine going from eight billion to two billion people on Earth, which is more plausible. Imagine the suffering involved in losing six billion people. You can’t even imagine it. Maybe that’s why it’s either Star Trek or extinction.


Question: What gives you hope?


PK: The only thing that has to happen to fix this, is the public waking up. If we had money in this, regulations, policies, the transformation could be ridiculously fast. The World War II mobilization people talk about really could happen, if we wanted it to.


Question: What is one piece of information that you wish each American had about the climate?


PK: Flying on an airplane is much worse than you think. If you fly more than once a year, it’s probably your greatest source of carbon. Making other changes, solar panels, etc., is meaningless if you don’t make this change.

Therefore, not to fly, or to reduce your flying, is one of the most important lifestyle changes you can make for the environment.

It took me three years to get to not flying. At this point, I’d have to have a really good reason to fly. A vacation, for example, wouldn’t cut it. Something for which I had to be there in a few hours—perhaps if the Republican senators called and said, ‘Dr. Kalmus, we need you to testify in Washington about the climate and we’d need you there by tomorrow so you can’t take the train. We’re ready to listen.’


I believe I am on the right side of history–I have to pay a social price and a career price for my advocacy, but I don’t feel my efforts are wasted. It’s hard leading out front on a cultural issue. We all want to pretend it’s all OK. We don’t want to stop flying, and I don’t think we’ll be ready to listen until we have a culture shift.


Question: How do we create this culture shift?


PK: That’s why reducing personal emissions is way more important than people think. It’s not simply to keep your emissions out of the atmosphere—the amount is too small by itself—but because by doing so, you are shifting the culture. You are normalizing a different way of life.

For example, you wouldn’t be talking to me right now if I hadn’t reduced my emissions.

I would have thought so many climate scientists would have done this by now, but they haven’t because the culture hasn’t shifted yet.

Also, burning less fossil fuel will make you happier! For example biking instead of driving or taking the train rather than flying, gives you a good period of reflection, solitude, and connection.


  1. Question: How has your meditation practice impacted how you approach this work?


PK: One thing that meditation teaches me is that I can control my decisions, but no one else’s. And if I allow myself to feel angry or depressed about others’ decisions, that’s a suffering that I don’t need. There is a sort of beneficial detachment you get from meditation. Your ability to be happy is separate from others’ decisions. Good things happen to you, bad things happen to you. That’s just life.

Also, climate change, in a sense, may be forcing people to look directly in the face of their own mortality.  I think this is part of why climate change is considered impolite to talk about at a dinner party.  We are good at living our lives by compartmentalizing and shoving that aside.

But now it’s also an opportunity for us to empathize and see the suffering of our fellow humans—and non-humans. The non-humans may be even more important because coral reefs don’t get interviewed, they don’t go to conferences. They don’t have a voice. Climate change is a real crossroads for humanity. It’s a test for our gratitude and empathy. Are we going to take our planet for granted, or will we realize how precious it truly is?

There’s always been a good reason to meditate: Pretending we’re not going to die is a source of suffering, because we know we will die and it hangs over us subconsciously. Instead, meditation makes you happier, because you are doing useful work with this certain knowledge that we are doomed, and it’s OK. (And I mean that in a positive way—knowing we are going to die gives life meaning.) Some of us try to live the best life we can—not despite that knowledge, but because of that knowledge. This is all mirrored in climate change.

You can do everything you can: Burn less fossil fuels, try to shift the culture—and it’s deeply meaningful and beautiful to have an opportunity to have such a clear call, for your life to be so clearly visible. It’s sort of an opportunity.

Especially because we’re now seeing the climate impact. For example, my avocado tree almost died when it reached 118 degrees F in California this summer. No amount of water could get that tree through unscarred. My lemons turned into brown mummies. My experience of being in my garden now has a dark side to it that it didn’t have even a few weeks ago.

I don’t believe in false hope or false optimism, but I believe in active hope. We can still find hope. It has to be real. it has to come from conversations like this.

For me, it’s the hope that people will be able to wake up rapidly, and shift rapidly. The human part seems so non-linear to me, so inherently unpredictable, so therefore a source of hope. Don’t assume we can’t change quickly enough, because we don’t know that. We need strong leaders, and voices. We need people leading by examples.

This idea that life could be more enjoyable through cutting my emissions is what inspired me to write my book, Being the Change: Live well and spark and climate revolution.  Before, I could find no examples of people living without fossil fuels, so there was no one to say: ‘By the way, you might enjoy it!’ A world without fossil fuels might be better!’”


The End