Do email signatures really hurt the planet and cost people their lives?

This press release responds to a widely circulated article claiming that email signatures, especially those including pronouns or land acknowledgments, pose a measurable threat to the environment and human health. In our detailed analysis, we challenge the study's conclusions, highlight serious methodological flaws, outdated data, and misleading interpretations. At the same time, we aim to  refocus the conversation on what truly impacts the sustainability of digital communication and how companies can implement professional, effective, and environmentally conscious email signatures. 

An article from The Conversation based on a study by Joshua M. Pearce (professor at Western University, holding the John M. Thompson Chair in Information Technology and Innovation) has been making rounds lately about the damage email signatures pose to the environment. The study points out that any additional data added to an email increases the energy consumption required to transfer it. The author then quantifies the impact on human lives, specifically looking at pronouns and land acknowledgments by Canadian email users. 

As a brand invested in the email signature business, it caught our attention – and the more we looked into it, the more cracks we saw. 

The numbers (don't) lie 

Pearce distributes global email volume by population percentage, which is flawed. He admits this: 
'The volume of email sent by richer nations like Canada would be expected to be much greater than poorer countries…' 
He also uses an 'average email length' of 434.48 words, from a marketing blog about newsletters – not everyday emails. 

Let's test real email content. One of our recent emails had 15,794 characters; the body (with formatting) had 10,252 – meaning content made up about 65% of the total. 

Pearce claims pronouns add 3/435 = 0.7%. But in our case, adding "he/his" increased the size by 0.1% – a much smaller impact. 
So right from the get-go, we find ourselves in a territory of wild estimates. Maybe the responsible thing for a researcher would be to pause and dig for better data than extrapolating global numbers like this, but hey, we're just some guys from a SaaS company and not academics, so what do we know? 

What year is it? 

Pearce uses 4g CO2 per email, citing a 2010 source ('How Bad Are Bananas?' by Mike Berners-Lee). But the 2020 edition revised those numbers down significantly: 

0.03g CO2e spam email picked up by your filters 

0.2g CO2e short email going from phone to phone 

0.3g CO2e short email sent from laptop to laptop 

17g CO2elong email that takes 10 minutes to write and 3 minutes to read, sent from laptop to laptop 26g CO2e an email that takes you 10 minutes to write, sent to 100 people, 99 of whom take 3 seconds to realise they should ignore it, and one of whom reads it 

The energy use has dropped due to more efficient devices. Yet Pearce uses the outdated 4g figure. Worse still, he doesn't distinguish between CO2e or CO2 equivalent – an error that would result in a failing grade for a freshman in any climate-related studies.

So… what's the number? 

It's currently not possible to determine even a ballpark CO2e figure when it comes to including pronouns (or land acknowledgement declarations) in emails. It's not zero, but it's definitely far lower than the numbers proposed by Pearson.

Pearce further invokes the '1000 ton rule' – claiming every 1,000 tons of carbon burned kills one future person. This figure is shaky at best. He also converts 1,000 tons of carbon into 3,700 tons of CO2 – which is incorrect (the actual conversion is 3,670 tons). 

Following his alarmist conclusions, Pearson continues to advise on how to mitigate the imagined impact: 

Pearce recommends showing pronouns only in the first email or using a hyperlink. But this doesn't help — Gmail caches signatures and hides repeated content. The energy saved from omitting a few characters is negligible compared to the power needed to run devices. 

Also, hyperlinks are often longer than the pronouns themselves. 

Why focus on pronouns and land acknowledgments when email images or unnecessary attachments have a far larger footprint? 

Something we do agree with 

Yes — cluttered signatures waste space and look unprofessional. Some emails don't need to be sent at all. Even small changes can improve both sustainability and communication. 

At SignatureSatori, we help companies create effective, sustainable, and professional signatures. 

I will leave you with Berners-Lee's paragraph that he used to finish his chapter on emails in the 2020 book version. It contains more accurate numbers and is far more thought-provoking while being grounded in reality than the whole Pearson's study: 

'If only email were taxed. Just a penny per message would surely kill most spam. The funds could go to tackling world poverty or even renewable energy. The world's carbon footprint would go down by 2.4 million tonnes, the average user would be saved a couple of minutes of time every day, and there would be a £480 billion annual fund. If 1p turned out to be enough to push us into a more disciplined email culture – with perhaps half the emails sent – the anti-poverty fund would be cut in half, but our lives would still be significantly better. The (small) carbon saving would be an additional bonus.'