Flying less is greener

Because of a recent Washington Post piece by Sam Denby, it seems like a good time to collect some principles for fair reporting about the environmental impact of several transportation modes.

Principle 1: Report that less long-distance travel benefits the environment

What matters most is how much long-distance travel we do. There are many ways of reducing the average frequency of long-distance travel events while preserving what is important in our work and valuable in our lives. Sam Denby’s piece discusses trips from Dubai to Sydney and from Frankfort to Washington, but it is silly to hold miles constant when discussing such trips. The alternative to flying from Dubai to Sydney is not driving the same route. The alternative is flying less, and it is definitely greener.

Principle 2: Never exaggerate small improvements over bad options

One could compare a flight from Chicago to North Carolina to a single person driving in a car for the same journey. But that trip alone in a car for 820 miles already has a large carbon impact. A family of four environmentalists, if they must travel to North Carolina, can drive. A single environmentalist, who must travel to North Carolina, can consider a bus. We cannot as a nation meet our climate commitments if we travel too often from Chicago to North Carolina. We must contemplate the value and frequency of the trips.

Principle 3: Report equivalent comparisons across transportation modes

On those occasions when, as just one part of a broader analysis, it makes sense to compare transportation modes holding constant the trip distance, then make the comparisons fair.

Option 1: best cases. If you measure miles per gallon (mpg) of a fancy new jet operating at full capacity, then compare it to the passenger mpg of a cutting-edge electric train, a new bus at full capacity, and a hybrid car with 4 passengers.

Option 2: average cases. Alternatively, if you compare trips for average automobile mpg and occupancy, then your computation for flights must: (a) use actual occupancy rates for flights, and (b) use averages for the real-world fleet, not best cases for fancy new planes.

Existing media reports

Let’s look at some actual examples in recent media coverage. I feel Sam Denby in the Washington Post does poorly by these principles, but you can judge.

Fivethirtyeight in 2015 has the title “Every Time You Fly, You Trash The Planet — And There’s No Easy Fix.” This piece does well, emphasizing global carbon emissions goals and assuming that traveling less is one of the options. Denby criticizes the actual transportation mode comparison, because the data source was a carbon offset company, but Denby doesn’t actually say what’s wrong with the numbers, and it seems to me the comparison here does not exaggerate the environmental harm of flying. It seems to basically agree with the other sources discussed below.

Much of the recent controversy arises from the work of Michael Sivak at the University of Michigan, which argues that the efficiency of flying has improved relative to the efficiency of automobiles. I like it that Sivak attempts to follow “option 2” above for consistent comparisons. I don’t know enough about engineering to reconcile his numbers with somewhat differing numbers from environmental organizations. A nice article at Yale Climate Connections treats Sivak’s estimates as authoritative. On the other hand, a somewhat earlier 2013 analysis by the International Council on Clean Transportation somewhat disputes the numbers, making flying look worse than other modes on a passenger mpg basis. For me, the key thing is that Sivak’s numbers do not really make frequent flying look green. Of the existing sources, Sivak’s estimates are comparatively favorable to flying when reporting under “Principle 3” above, which may be fine as far as it goes. But to report the truth more broadly, we must still keep in mind “Principle 1” and “Principle 2”.

My own summary of this complex literature is simple and short: Flying less is greener.




Nature envisions “a greener culture” for scientists

In Nature today, Julia Rosen gives an inspiring overview of scientists around the world who are innovating to reduce the climate impact of their work, with a special focus on flying less.

The article begins with the experience of Stephanie and Fraser Januchowski-Hartley, who traveled from the UK by bicycle and train to the International Congress for Conservation Biology in France:

By eschewing air travel, the pair prevented carbon dioxide emissions of roughly one-half of a metric tonne, and received the Swarovski Optik Green Travel Award from the Society for Conservation Biology, which hosted the meeting.

Rosen reviews the research of #flyingless supporter Shahzeen Attari, whose work shows that “walking the walk” enhances credibility for scientists speaking about environmental issues. She also has thoughtful reflections from one of our founding supporters, Alexandra Ponette-González, who contemplates the distinct challenges for early career researchers.

In the article, Rosen covers our #flyingless initiative at some length. If you arrived to this page through a link from Nature, let me take a brief digression to welcome you and tell a bit about our project. A group of university researchers around the world, including Joseph Nevins (at Vassar College) and myself (Parke Wilde at Tufts University) and many others, started this project in 2015 to encourage university communities to make sharp changes in the carbon footprint of their flying. We have an FAQ page with extensive information about scientific questions (how much does flying matter?) and personal questions (how can I change my flying without ruining my career?). We have a general petition page and a list more specifically of more than 430 wonderful academic supporters. We have an active Twitter feed @flyingless, which provides a good introduction to the work of other people on this topic. Our philosophy places high value on combining personal change with collective action and advocacy. The most important things you can do to help us are (1) if you are a scientist or academic who recognizes the importance of vigorous action toward flying less (even if you still fly yourself), please email us to be added to this list; and (2) please share the site as widely as possible.

In my own comments, quoted in Rosen’s article, I tried to communicate the value of flyingless for people at diverse stages of change, ranging from enthusiastic to reluctant. I noted that university communities can make a huge difference by flying drastically less, even if many academics are not yet ready to give up flying altogether. Still, on reflection, I may have spoken too mildly in this article. Climate change is an exceptional global challenge. Through self-experimentation, we have learned much about how to maintain a vibrant academic life while flying rarely. Several of us have not flown for years. If you are ready for this, don’t hold back and limit yourself to small steps!



The Carbon Code, by Brett Favaro


In The Carbon Code (Johns Hopkins University Press, 2017), long-time #flyingless supporter Brett Favaro embeds aviation issues within a broader agenda for personal and social change. Along with the energy sector, local and regional transportation, and the food sector, Favaro explains the magnitude of aviation’s impact for the total greenhouse gas (GHG) emissions of comparatively prosperous people:

For the average person, [commuting] trips make up most of the transportation footprint. For those of us in the top quarter of global wealth, the GHGs we emit from long-distance air travel can be far more damaging. We can’t ignore this any longer. The carbon cost of travel is enormous and growing quickly.

The book, written for lay audiences, (1) summarizes the science of consumption impacts on greenhouse gasses and proposes a code of conduct (hence, the title phrase, “The Carbon Code”), (2) reviews implications for daily life sector by sector, and (3) finally engages a broader conversation about cultural and political change.

The book is so terrific that I have added a new question to our Frequently Asked Questions (FAQ) list, citing this work. I will be sharing it with friends in my community.

In addressing aviation, Favaro writes:

Flight is a luxury. The vast majority of people on Earth never set foot on an airplane or do so very few times throughout their lives. If you fly regularly, then you are statistically an outlier. This is hard to wrap our heads around in North America and Europe, where flying is relatively common. But every time we travel by air, we are accountable for a large amount of carbon pollution. Climate justice demands that we examine this carefully.


Changing the culture of university communities (a #flyingless update)

Here are three recent links emphasizing #flyingless themes in a constructive way.

  1. The March 28 event at KTH Royal Institute of Technology in Sweden has now been posted online, and it’s wonderful. We appreciated the shout-out from Kim Nicholas for our initiative. Kevin Anderson illustrates in his own calm manner the hybrid radical realism that he espouses. Nowhere else in my academic life do I see PowerPoint slides with titles like, “Narrow thinking led to our shameful littany of scams.”
  2. Our own Joe Nevins, from Vassar College, has a new essay in truthout, emphasizing the combination of systemic and lifestyle changes. He warns against “a ‘soft denialism’ shared by many associated with the broad left and the climate movement in the United States and the West: a failure to scrutinize lifestyle and everyday consumption.” At the same time, he emphasizes the need for systemic change focused on environmental justice. He writes, “collective action and individual action are necessarily linked in the effort to make structural change. Like any project of far-reaching change, the effort to radically cut carbon dioxide emissions, and environmental degradation broadly, is a multi-front endeavor.”
  3. Registration is now open for the Global Arts and Psychology Seminar (GAPS) on April 28-29. Here are links for registration for the Boston hub, which will be 9:30am to 2pm on April 28 at Tufts University, and for the global event. As the keynote speaker for the Boston Hub, Emily Morgan, Ph.D., a researcher at Tufts, will discuss “Modeling Melodic Expectation.” In format, as a small-scale pilot, this event offers one step toward addressing a challenge Kevin Anderson raised in the Swedish event in #1 above, reflecting on the need for experimenting with new methods of long-distance or virtual academic connection that preserve the essential warmth and human connection of in-person conferencing. Join us at the hub nearest you!

Innovative multi-hub Global Arts and Psychology Seminar (GAPS), April 28-29, at universities around the globe

Graz, Austria, one of five hubs.

The Global Arts and Psychology Seminar (GAPS), on April 28-29, will bring together graduate students and scholars around the globe, especially in music and psychology. There will be integrated keynote talks, breakout sessions, and workshops, at universities in 5 hubs:

  • Graz, Austria
  • La Plata, Argentina
  • Sydney, Australia
  • Sheffield, UK
  • Boston, USA

The seminar offers a novel mix of in-person and virtual conferencing. It is a pilot run for a possible major professional conference in summer 2018.

The request for papers invites graduate students to submit brief abstracts. The deadline for abstract submission is Apr 7. Existing or previously presented papers are welcome.

The lead organizer and innovator is long-time #flyingless supporter Richard Parncutt, a professor of systematic musicology at Uni Graz, Austria. “The purpose of the new conference format is to go global,” Parncutt says, “opening up to colleagues in as many countries and regions as possible, regardless of financial means.” He suggests the conference can halve CO2 emissions per participant by eliminating most of the flying. For practical reasons, the project is starting with a relatively small number of hubs, but the “cloudcast” approach means that the number is practically unlimited: each hub transmits its local presentations live to the cloud and all other hubs can choose which presentations to include in their virtual program, either live or with a time delay.

I’m personally delighted that my university, Tufts University, will host the “Boston” hub — the actual location is the university’s Medford/Somerville campus. For this hub, the schedule is entirely on Apr 28. Tufts has a long record of great work in music and psychology, including by former provost Jamshed Bharucha and current internationally known music psychology professor Aniruddh Patel. As the organizer for the Talloires Declaration, Tufts also has been a leader in encouraging university communities to develop more environmentally sustainable operations during a time of climate change.

This event offers a distinctive combination of in-person presence at each hub and global reach across the hubs. We will be connected virtually, but the coffee in the morning, the handshakes with new colleagues, perhaps the glass of wine at the end of the day, and the sense of an exciting event in the conference rooms themselves, learning about important new research in music and psychology, will all be real. I hope to see you there!

Tufts University, Medford/Somerville Campus — the “Boston” hub.

New work from #flyingless academic supporters

Members of our list of #flyingless academic supporters have been busy!

  1. This coming Tuesday, March 28, KTH Royal Institute of Technology in Sweden is hosting an event that poses the striking question, “Should scientists stop flying?” The subtitle is “decoupling knowledge from carbon in an age of climate change.” It includes Kimberly Nicholas (Associate Professor of Sustainability Science, Lund University Center for Sustainability Studies) and Kevin Anderson (Zennström Professor in Climate Change Leadership, Uppsala University, and Deputy Director of Tyndall Centre, UK). Of course, the event will be livestreamed.
  2. It’s time to wake up to the devastating impact flying has on the environment,” writes Roger Tyers (Environmental Sociologist, University of Southampton), in a recent article in the Conversation. “Aircraft are becoming more fuel-efficient, but not quickly enough to offset the huge demand in growth.”
  3. Supporters James Higham, Francis Markham, and colleagues also have a recent article in the Conversation, “Life in a post-flying Australia, and why it might actually be ok.” They offer counterpoints to nine commonly heard objections to this claim.
  4. Rupert Read offers an article in Medium with the title, “Climate change is a white swan.” He writes: “There’s nothing unexpected about the coming catastrophe: it is approaching us ‘smoothly’. And yet we’re doing so little to stop it. What gives?”

If you are an academic, and would like to be added to our list of #flyingless supporters, or if you already are a supporter and would like to share your recent writing, please email

Organizing webinar meeting Oct 27 links #flyingless activities at universities around the globe

As the keynote speaker for the #flyingless initiative’s organizing webinar, held on Oct 27, Dr. Ruth Wood summarized several activities of the Tyndall Centre for Climate Change Research in the UK relevant for academic communities that are taking steps to reduce flying.

Wood is an author of the Tyndall Centre’s 2015 working paper, “Towards a Culture of Low-Carbon Research for the 21st Century.” In connection with its research program, the Centre has developed a travel strategy, including a code of conduct for researchers. An accompanying online travel tracker tool provides a mechanism for recording progress toward institutional goals.

“To be credible and maintain our integrity,” Wood said, “we should limit our emissions, from travel and from flying.”

In its second half, our organizing webinar also provided an opportunity for approximately 18 participants to meet each other, ask questions, share resources, and catch up on activities and efforts at universities around the world.

We discussed:

  1. Ways of increasing our growing list of academic supporters. Current supporters are encouraged to reach out directly to at least 2 new colleagues.
  2. Efforts to enhance the visibility of aviation in “Scope 3” emissions reported by universities using a framework coordinated by the Association for the Advancement of Sustainability in Higher Education (AASHE).
  3. Improving the climate impact particular major annual conferences, such as the American Geophysical Union or the American Academy of Religion (which is contemplating a proposal to do something different from the usual conference in 2021).
  4. Increased social media activity through the Twitter hashtag #flyingless and handle @flyingless.
  5. News coverage in major media.
  6. Building bridges with related movements (runway opponents, fossil fuels divestment, environmental justice, simple living).
  7. And more!