Peter Kalmus

Atmospheric Scientist
Peter Kalmus

Before I estimated my CO2 emissions, I had no idea that flying accounted for almost all of it. In 2010 I made a simple pie chart of my emissions. 50,000 miles of flying, almost all in the name of science, took up 75% of the pie chart! Obviously, no other reductions to my emissions really mattered until I stopped flying.

With a realistic sense of the impact of my flying, it came to feel wrong. I also began to question how necessary it was. In 2011 I flew 20,000 miles, and by 2012 I’d stopped flying. I’ve attended meetings remotely, traveled to them by train (although diesel-powered trains in the US aren’t as low-energy as you might think), and I’ve even traveled on a container ship (which was carrying atmospheric instrumentation such as radars and weather balloons for a field campaign). I drive all over the United States in a 35-year-old car that burns 100% waste vegetable oil from a local sushi joint. I find slow travel to be adventurous, a great way to visit old friends and get in some backpacking, and — if on a train or a ship — a great way to focus and get lots of work done. The old car is a fun thing for me because I enjoy the engineering challenge of keeping it running and out of the landfill! The higher that old odometer rolls, the prouder I feel.

I don’t currently foresee a need to fly. My close relatives live in the United States, and in case of emergencies I can drive or train to be with them.

Once I stopped flying, it did make sense to address my other sources of emissions. I currently emit less than 2 tonnes of CO2 per year, a tenth of the US average. I still look for ways to further reduce my emissions, but now I’m more interested in sharing what I’ve learned and helping people in my community reduce their emissions, too. Many of these people are inspired by my changes and have made significant changes of their own. I’m not under any illusions that my personal reductions have a significant impact when weighed against the emissions of more than 7.5 billion other people. But I believe that in making the changes I’ve made, I’m telling a new story and showing people what’s possible. Plus I just like it better.

My experience is that effective advocacy starts when we change our own lives. I’ve found it empowering to reduce my own emissions, and also surprisingly fun. I haven’t found low-energy living to be a sacrifice.

Peter is an atmospheric scientist at the Jet Propulsion Laboratory / Caltech, speaking on his own behalf. He uses satellite and in situ data to study clouds, tornadoes, and climate. He obtained his Ph.D. in physics from Columbia University, and originally searched for gravitational waves with the LIGO collaboration before switching to Earth science due to a need to learn about climate change. His book, Being the Change: Live Well and Spark a Climate Revolution describes what one person can do in response to the massive problem of global warming. Peter is the founder and editor of