Sustainable Science

Climate change is an urgent threat to biodiversity and human health (IPCC Report). While emissions from aviation are currently less than 10% of all emissions they: (1) are expected to grow rapidly over the next few decades, (2) dominate the personal emissions of those wealthy enough to fly regularly (Carbon Footprint Calculator). Recently, a group of climate scientists have publicly pledged not to fly, in order to reduce their carbon emissions and show scientific leadership on climate (No Fly Climate Sci).

These facts raise important questions: What is the annual carbon footprint of scientific research? Here I'm focusing on my field, neuroscience, but these questions apply broadly. What steps can be taken to reduce that carbon footprint? On this page I outline concrete steps that individuals as well as conference organizers can take to reduce the carbon footprint associated with travel for talks and conferences. I believe that smart policies can reduce carbon emissions, while also improving access by less-funded labs and early career scientists. For information about other ways to address climate change, check out My Green Lab, and Citizens' Climate Lobby

How much carbon can one conference generate?

To develop a sense for how large the neuroscience field's carbon footprint is, I can perform a simple calculation focusing on one conference, SFN. Society for Neuroscience's annual conference has about 30,000 attendees. I'll assume those attendees are traveling on average across the US. Certainly some people are traveling less, but many are traveling farther from Europe or Asia. A roundtrip economy class flight from NYC to San Diego will produce about 2000 kg of CO2. That results in a total conference emissions from air travel alone of 60,000,000 kg of CO2 every year! That's the equivalent to the annual emissions from 13,000 cars (source). Academic scientists are privileged in education, power, and resources. We therefore have a duty to reflect the urgency of climate change in our actions.

If you are an individual

A) Ask conference organizers what steps they have taken to reduce the carbon emissions related to conference travel. Systematic changes to our field have a larger impact than person reductions. Specifically:

(1) Ask conference organizers to calculate and publish the carbon footprint of the conference.

(2) Ask conference organizers to make the conference more accessible by putting talks and posters online.

B) The best way to reduce your personal emissions is not fly to a conference. I understand that conferences have value in advancing our field and our careers, but reasonable moderation in conference attendance is easy to implement. Is travel to that destination conference worth the money and carbon emissions? Can you attend or present at the conference virtually?

C) If you decide to fly to a conference, get the most out of the trip.

(1) Can you combine this conference trip with something else? For example, after attending the conference can you visit a colleague at a nearby university? Can you combine the trip with a vacation you were planning on taking anyways?

(2) Put your poster or talk slides online. Its very easy to post them to twitter, where many people will see them. By doing this your allow people who did not attend to learn about your work. By doing this you make it easier for other people to reduce their emissions. Further, you let people without the economic resources for conference travel, including undergraduates and under-funded scientists, to have access to a more level playing field. In my experience, putting a poster online means more people look at it.

D) If you decide to fly to a conference, limit your impact.

(1) Offset your carbon emissions. Offsetting emissions means paying someone else to stop emitting, or take some action to remove carbon from the atmosphere. The ethics of carbon offsets are complex, as they may let people justify emitting more. In my opinion, reduce what you can, and offset the rest.

(2) Take direct flights, and fly coach. Both of these actions will reduce the carbon emissions of your trip. Obviously if there is a non-flight option like a bus or train, take that instead.

E) Use your voice, and status as a scientist. Talk with your colleagues and friends about the carbon footprint associated with travel. Ask your lab or institution to offset travel emissions.

If you are a conference or talk organizer

A) Plan conference locations to reduce emissions and facilitate non aviation transportation.

B) Record all talks, and post the videos online so non conference attendees can watch. This lets people reduce their emissions, and also gives access to under-funded scientists.

C) Put electronic copies of posters online in a central repository.

D) Allow people to give virtual talks. During a talk everyone looks at the slides anyways, not the individual.

E) Calculate, publish, and offset conference emissions.

F) Establish a sustainability coordinator for the conference, to plan and execute sustainability goals

G) Make a plan to achieve a zero-carbon conference

At your institution

A) Calculate, publish, and offset institution emissions

B) Update travel policies that allow and encourage low-carbon travel options like trains, buses, and virtual attendance

C) Establish a sustainability coordinate for the institute, to plan and execute sustainability goals

C) Make a plan to achieve zero-carbon operations

Case Study, Cosyne 2020

Cosyne 2020, a computational neuroscience conference, offered optional carbon offsets as part of the registration process. A more in-depth analysis is needed to know participation rates, what fraction of emissions were offset, and the quality of the offset program, but this gives an example of how conferences can approach this issue.

On the registration page they wrote:

"Cosyne 2020 has partnered with Native Energy, an organization dedicated to helping build Native American farmer-owned, and community-based projects. Post-conference, we will contribute to the Jagers Ranch Grasslands Conservation project in southeastern Colorado in order to compensate for the conference-related CO2 emissions. Attendees are encouraged to join us in this effort. Within the registration for the conference you will have the option to *compensate the CO2 emission of your travel. You may opt-in at a set amount of $15 (approximately one metric ton), or an amount of your choosing in increments of $1.00.

* Please consult your institution/organization in advance to determine if the expense is reimbursable. "

After the conference they reported:

"Dear Cosyne 2020 Attendees, with your action to address carbon emissions related to conference travel, the Cosyne conference collectively reduced 357 metric tonnes by supporting the Jagers Ranch Grasslands Conservation Project. Thank you."

For a rough order of magnitude calculation lets assume 1000 people attend COSYNE each year, each traveling on average across the US, we can estimate a total carbon footprint of 2,000,000 kg (using the same math as above for SFN), or 2,000 metric tons of CO2. That means this voluntary offset program, in its first year, offset roughly 18% of the carbon emissions of the conference. COSYNE did little to advertise, or motivate this voluntary offset. Perhaps future COSYNE conferences will have a higher participation rate. In 2020 the student/postdoc registration fee was $265, or $510 including the workshops. The academic rate was $375/$730. Using my estimate of 2000kg/person for air travel, offsetting these emissions increased the registration cost by ~4-10% depending on position and workshop attendance. The percentage cost is even small when including the cost of hotels and food.


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