Email signatures are harming the planet and could cost people their lives — it’s time to stop using them

The use of information technology (IT) has significant environmental and social impacts, including human mortality from climate change. One striking example is the carbon emissions and impacts associated with digital communication.

To quantify the human cost of carbon-emitting technology, researchers use the 1,000-ton rule that estimates that for every 1,000 tons of carbon dioxide released into the atmosphere, one person dies prematurely.

This rule is derived from the following calculation: burning one trillion ton of fossil carbon is likely to cause 2 C of anthropogenic global warming, which in turn is likely to cause about one billion premature deaths spread over the next century.

This theory can be used as a decision-making framework for policymakers to compare the value of an activity to the cost of that activity in human lives.

It’s also what I used in my recent study that analyzed how additional information in email signatures contributes to climate-related deaths in Canada.

Email signatures causing emissions

Sending emails is an everyday activity, but it comes with an environmental cost. Emails use energy, and that energy often comes from burning fossil fuels, which in turn, contribute to increasing atmospheric carbon dioxide levels.

The overwhelming scientific consensus is that human activity is destabilizing the climate and is likely to cause irreversible damage to the global environment and humanity.

My recent study explored the environmental impact of lengthening email signatures, focusing specifically on two types of information: gender pronouns and land acknowledgements because both are relatively new additions to email signatures.

In both cases, the extra carbon emissions for each email for the extra characters is estimated and aggregated over the population that uses them.

The results showed that in Canada, where about 15 per cent of people include gender pronouns in emails, the resulting carbon emissions from this small change (three extra words) may contribute to the premature deaths of one person a year, according to the 1,000-ton rule.

The environmental harm and human mortality caused by this seemingly minor digital habit is evident. Large blocks of text like legal disclaimers and land acknowledgements cause even more harm. Images and logos, which contain even larger amounts of data, cause more emissions and deaths still.

Doing away with email signatures

Most of the content in email signatures is redundant, as we tend to email the same people repeatedly. The environmental and human cost of using email signatures clearly outweighs the benefits. One solution to this issue is to replace email signatures with a hyperlinked name to additional information.

Another simple way to increase efficiency and reduce emissions is by eliminating email signatures entirely, since emails already identify senders in the header. After all, we don’t sign our texts, so why do we feel the need to sign our emails?

If you receive an email with a long signature, you might consider asking the sender to switch to a hyperlink instead, or eliminate their signature all together.

Additionally, you can encourage others to use free, open-source ad blockers to reduce unnecessary data from ads while browsing or emailing. Ads, especially on websites, generate an enormous amount of unnecessary data and energy consumption.

While these steps may seem small on their own, collectively, they can make a significant difference in reducing digital waste and unnecessary emissions.

The hidden cost of spam emails

The results of my recent study make it clear that Canada’s current IT and energy infrastructure are unsustainable. The study should serve as a wake-up call for the need to eliminate the use of fossil fuels from our energy systems entirely, particularly because it is already possible to displace fossil fuels with renewable energy with lower costs.

It also gives pause for the far more damaging impacts of other forms of digital communications, particularly email spam.

Spam accounts for over half of all emails and, despite having lower carbon emissions per email (since many are deleted without being opened), spam accounts for far more emissions-producing data. Beyond its environmental toll, spam also wastes the time of every email user.

In response, several proposals and laws have been put forward to reduce this digital waste, from including taxes on emails, opt-in or opt-out systems to even outlawing spam entirely. While these efforts are a step in the right direction, we all still suffer through an enormous amount of spam.

The environmental impact of our online habits is far larger than most realize, and as digital communication continues to evolve, we must consider its long-term consequences on the environment and human life. We should take the easy steps of cutting wasteful energy use in our communications and it can start with eliminating email signatures.