According to a McAfee report,
Until now, spam’s impact has been measured in time, money, and aggravation. It turns out there is a massive environmental impact as well. McAfee recently commissioned climate-change consultant ICF International and spam expert Richi Jennings to calculate the environmental impact of spam. The results that came back were startling: The energy consumed in transmitting and deleting spam is equivalent to the electricity used in 2.4 million U.S. homes, with greenhouse gas (GHG) emissions equivalent to 3.1 million passenger cars(http://resources.mcafee.com/content/NACarbonFootprintSpam)
I first learned about these findings through ABC. Essentially,
Anything powered by electricity also emits greenshouse gases. McAfee researchers say each junk e-mail emits 0.3 grams of the greenhouse gas carbon dioxide (CO2). That may not sound like much, but when you consider the volume of global annual spam, it all adds up. (http://abcnews.go.com/Technology/GlobalWarming/story?id=7343518&page=1).
Following that reasoning, spamdexing search engines and any adversarial information retrieval (AIR) practice is also an insult to injury, so as too many things that comes to my mind.
I will tell that to students of my Fall 2009 AIRWeb Course.
Humm, shocking: AIR vs. Environment.
I never thought about such an obvious connection.