a3nm's blog

Some random notes from the "Labos1point5" day (November 6, 2020)

I attended the first day of the Labos1point5 French group about reducing the carbon footprint of research. It was held fully online, and I found it very interesting. Here are some quick notes of initiatives and resources that I heard about via this day. (The Labos1point5 day was entirely held in French, and almost all resources linked here are in French, but the question of climate change isn't specific to France, so I'm writing this list in English.)

CO2 impact of computation

  • A French estimate of the carbon footprint of computation is available here: here. (The result is about 5 grams of CO2e per hour of core CPU time.)
  • The rule of thumb for the environmental impact of computing equipment is that, usually, half of the footprint comes from producing the equipment, and half of it comes from use (electricity consumption).
  • In terms of computing time, a useful rule of thumb is that larger datacenters are usually more efficient that smaller ones, thanks to economies of scale. This is an argument for mutualizing (e.g., avoid smaller local data centers), though there are of course other issues (confidentiality...). Here are details and pictures about a French datacenter with passive cooling; there are other French companies active on the green datacenter front, e.g., Webaxys.

CO2 accounting

  • It is now compulsory for sufficiently large companies and public bodies in France to do a regular carbon accounting report to estimate their GHG emissions. For this reason, many people are now looking into measuring GHG emissions, which is a good thing, and investigating how to classify them according to complex accounting rules, which is less interesting but probably unavoidable. This carbon accouting is often delegated to specialized companies. These GHG emission reports are often publicly downloadable (here). Here are the legal details of the requirements.
  • The ADEME provides very extensive data to estimate GHG emissions for various activities, including transportation. The dataset is here. The Shift project also has such a dataset for computing: the REN.
  • A nice graphic of the carbon footprint of French citizens, here. This is about 12 tons of CO2e per person, to be compared to the 2 tons per year that would be sustainable.
  • The environmental impact of computing is studied by the CNRS group Ecoinfo in France. In particular, they provide a tool to estimate the CO2 footprint of computing equipment.

CO2 accounting and reduction in labs

  • The labos1point5 group is proposing an online tool for French research labs to measure their carbon footprint. This tool is called GES 1point5, there is a video presentation here.
  • Another "regulatory" idea is to integrate criteria about greenhouse gas emissions when doing calls for bids when buying equipment, and ask suppliers for an estimate of the carbon footprint of what they provide. This can be a way to compare suppliers, and encourage them to take this criterion in consideration.
  • Many French research institutes are starting to investigate the carbon footprint of the professional travel of scientists. To do this, it is necessary to track which travel is taking place. In some places, this goes together with the need to modernize the way professional travel is ordered (i.e., having a Web interface rather than paper forms). This kind of modernization is a good way to start GHG accounting.

Efforts in reducing CO2 emissions in labs, and political questions

  • The Parisian ocean research institute LOCEAN now performs accounting of their GHG footprint (including professional travel and sea travel). They voted (details here and here) to reduce their GHG footprint, in particular putting a cap to limit the emissions of the flights of each faculty (from 10 tons CO2e in 2021 to 2.5 tons CO2e in 2026). This vote was the result of a long process of discussions with all affected faculty to convince them. For this, you have to be ready to accept counterarguments, give time for people to digest the issue and change their minds, and argue against the same common objections coming again and again from different people.
  • A common argument against limiting the carbon footprint of research is that research is a "useful" activity, e.g., the carbon footprint of flights for scientific conferences is better used than the same footprint for mass tourism. A good retort to this argument, however, is that scientists are (or should be) better informed than the general public about the issue of climate change and the need to reduce carbon emissions. Hence, the people who are informed about the issue have a duty to lead by example, so as to convince more people to act.
  • There have been scientific studies of the necessity of flying for academic success (in terms of numbers of citations), see Wynes et al., Academic air travel has a limited influence on professional success (link), or Chalvatzis and Ormosi, The carbon impact of flying to economics conferences: is flying more associated with more citations? (link, does not seem available in open access).
  • To modernize the practices of research to reduce its footprint, we should look beyond our immediate research area, to see what different fields are doing. Indeed, even though some fields have specific activities with a high footprint (e.g., experiments), some issues (e.g., flights) are common in multiple fields. A good source of inspiration is to look at what is done by researchers in climate science, which are of course better informed about the need to act. That said, it is disputed if they are really acting as much as they should, see, e.g., this study. There is also a paper spelling out the contradiction where sustainable transport researchers still non-sustainably fly to scientific conferences.
  • Reducing the carbon footprint of academia is connected to many other things that should be fixed in academia. In particular, a common theme discussed during the Labos1point 5 day was to do less research (but do it better). Indeed, the right way to emit less carbon might be cut the large proportion of travel, projects, papers, etc., that are of very little use and are only done to optimize the wrong indicators.

Other French initiatives

  • There are many French public bodies about climate that I didn't know about, e.g., the high council for climate.
  • In research, there is also the CIRSES association, which is trying to move higher education and research in the right direction.
  • The French dietary recommendations now integrate some information about the environmental impact of food choices.
  • I was also interested by the existence of a large-scale initiative to encourage vegetarian meals at the CROUS network of student canteens in Bourgogne Franche-Comté, details here CROUS.


  • The phenomenon of knowing about the climate crisis yet not doing anything about it has a name: the knowledge-action gap.
  • Interesting-looking seminars about ecology and research in Île-de-France : Ecopolien and Faire de la recherche dans un monde fini
  • An interesting idea: "Workdays for future", the idea of dedicating one day per week to work towards environmental issues.

Estimating carbon footprints: what is 1 ton of CO2e?

I just posted an article on the blog of the TCS4F initiative about how to understand the carbon footprint of various kinds of activities. You can read it here: Estimating carbon footprints: what is 1 ton of CO2e?.

Writing this kind of posts is a bit hard for me, because I'm certainly not an expert on climate change, so I don't feel very legitimate and hope that what I am saying there is realistic. Still, I hope that doing my own statistics is better than being completely in the dark. Anyway, reading about all this was the occasion to discover many surprising things about my own footprint, which can help me focus my efforts on the right areas. Personally here were the surprisingly high numbers, based on figures from the post:

  • The plane trips I take (most of which are for work) probably have a carbon footprint which is greater that all my other sources of emissions combined: several tons of CO2e per year, if not dozens of tons1. So this was the main takeaway: the number one area on which I should work is on travelling less to distant places : avoiding a transcontinental plane trip saves tons of CO2e emissions.
  • The carbon footprint of heating my flat (collective heating) is already about 1.2 tons of CO2e per year. Probably a bit less overall than the footprint of the food I eat, but certainly not negligible, even though I don't think much about it and have little control over it...
  • In a sense, the few Bitcoin transactions I have done last year may have ended up corresponding to several hundred kilos of CO2e on their own. I would never have guessed.
  • Not using a car probably allows me to save around one ton of CO2e per year in emissions from fuel for my commute, and several additional tons in terms of not having to produce the car.

And here were the surprisingly low numbers:

  • Avoiding meat only saves around 600 kg CO2e per year. This has a huge impact if everyone does it, but at my individual level it is rather small compared to the impact of one single long plane trip. Also, the most important food to avoid is unquestionably beef, and avoiding non-local food (e.g., bananas) does not seem to be worth it (see this study). So I'm still onboard with reducing my meat consumption, but transgressing every now and then isn't probably so much of a deal.
  • The carbon footprint in France is really low, thanks to the predominant use of nuclear power (not to mention other environmental costs, of course), so my total consumption of around 1800 kWh per year only represents around 18 kg CO2e.
  • Likewise, I was surprised to see that the estimated CO2e footprint of producing a mobile phone is only around 80 kg CO2e, and producing a T-shirt is only around 7 kg CO2e. Again, this says nothing of other environmental costs, but it is lower than I would have expected. I'm still not a fan of buying new hardware just for the sake of it, but apparently it's not such a huge deal in terms of greenhouse gas emissions.

I encourage you to read the post, which can hopefully give you a better idea of how your activities are producing CO2e, and what's the best way to help by reducing your emissions. And of course I'd be delighted to hear back if you have questions or comments about the results.

  1. I even went as far as trying to list all flights I took in my life, which wasn't so hard (took about an hour, if I didn't forget any). There are 125 flights, amounting to a total of 408 thousand kilometers, i.e., going over the world 10 times in total, or a bit over a one-way trip to the moon (!). This probably represents around a hundred tons of CO2e which is commensurate to what a sustainable lifetime carbon budget would have been for my entire lifetime (and with all emission causes combined)... One surprising point was that over half of this total is consumed by the 20 longest flights, so the biggest culprit is really long transcontinental trips. 

  2. In fact, I am a proud subscriber of Enercoop (in French), which means that in a sense I am already offsetting the footprint of my electricity consumption. 

No free view? No review!

I have blogged last month about my commitments for open access. Now, with Antonin Delpeuch and the CAPSH association, we are taking this to the next level and launching an initiative: No free view? No review!.

The idea is to give researchers a simple way to publicly say that they no longer want to review for closed-access conferences or journals, or prefer not to do it (we have kept the wording pretty open too). My hope is that will help show that many researchers support open-access, and get them to change their reviewing habits, which are easier to change than publishing habits.

So if you are interested, you can sign the pledge, advertise it on your webpage to stop closed-access reviewing requests, and spread the word around you!

Oh, and for another take on open-access and academia's flaws, last weekend I was thinking about that question: what if academia were an open-source project? And inspired by this, I wrote some contributing guidelines for computer science research. I hope this is fun to read — it certainly was fun to write. :)

Open access: my policy and my hopes

I care a lot about academic research papers being publicly available for free on the Internet, aka open access. In addition to describing this in my list of problems with academia, I recently wrote two things about open access:

  • A personal open access policy clarifying why I believe in open access, and which steps I am taking to promote it, in particular by refusing to review for closed-access conferences and journals. I have started to follow this policy since I was recruited as a tenured academic in August 2016, after having put up with the broken academic publishing system for several years during my PhD. Yet, it took me three and a half years of hesitation and discussion with my colleagues before I was comfortable enough to take a public stand on this. I hope posting this policy online will help colleagues understand my stance (in particular understand why I won't help them with reviewing for closed-access conferences), and that it will inspire other acts of disobedience against the statu quo.
  • A blogpost on the Database Theory Blog, co-written with Pierre Senellart. This is open access advocacy of a different kind, where we explain what would be possible in the saner world where the corpus of scientific papers were downloadable just like the Wikimedia datasets, or this impromptu mirror of LIPIcs papers that we prepared just because we could. Sadly, as we explain, this valuable resource cannot exist yet because it is currently hidden behind paywalls for historical reasons. It is our responsibility as researchers to move away from this model to unlock everything that should be possible with our research.

How to estimate your conference's carbon footprint

I have written an attempt at a guide about how to measure the carbon footprint of a scientific conference (or other event). This is largely inspired by the computation of the carbon footprint of the AGU 2019 Fall Meeting, and also by our experience computing the carbon footprint of SWERC 2019–2020.

This blogpost is published on the blog of the TCS4F initiative, an attempt by theoretical computer scientists to reduce the carbon footprint of our activities and help mitigate the climate crisis. I'm involved in the initiative (mostly as an author of blog posts, for now) and I have signed their manifesto: I encourage you to do the same if you agree with taking action on this important issue!

In any case, head here to read the blog post!