McAfee has published a 12-page report, compiled in collaboration with ICF international, which shows that the carbon footprint of every single spam message is 0.3 grams of carbon dioxide.
This multiplied by the estimated 62 trillion spam emails opened a Pandora box of figures and statistics, one more impressive and frightening than the other. For example, the report found out that one-fifth of the annual energy used by a medium-size business on email is associated with spam.
It is interesting to find out how McAfee and ICF worked their way to the final figure of 0.3 grams of green house gas. The first paragraph of the page 6 of the report spells it out. The energy use associated with each state in the Spam's life cycle was calculated. Then the appropriate emissions intensity to the total energy associated with spam and spam filtering was applied.
In other words, there was quite a few approximations and many extrapolations. Singularly, the report pinpoints the process of end-users deleting spam and searching for legitimate email, otherwise known as false positives, as the main generator of spam's CO2-equivalent emissions.
But that's not all. Spam, although very much present in our lives, occupies less and less headlines. Most of the job is done in the backend of email service providers which have not only made life more difficult for spammers but also, for many including myself, make the process of clearing out spam a distant memory. Gmail's spam system for example catches very few, if any genuine emails and allows the odd spam email to go through.
So what are the facts? McAfee, the security company which commissioned the research paper, sells anti-spam server applications. ICF is a climate change consultancy firm. The overwhelming percentage of spam - which according to Microsoft represented 97 percent of all emails sent worldwide - get caught by spam filters.
This means that the servers are doing the most tasks, not the human beings sitting behind their desks. Furthermore, collaboration between the major email providers like Hotmail, Gmail and Yahoo ensure that through features like SPF and white listing, the scourge of spam email is diminished.
McAfee unsurprisingly is the biggest winner since what essentially is a glorified white paper has managed to attract significant media coverage worldwide by lumping together two major global preoccupations: spam and global warming.
Spam is killing the planet
Spam and its Carbon Footprint
McAfee jumps on global warming bandwagon
Why the Spam Carbon Footprint Study is Wrong
The Carbon Footprint of Email Spam Report (PDF file)
Is Spam Really Threatening Planet Earth? I Don't Believe It