Plenty of pot-smokers have an eco-friendly, back-to-nature aesthetic, but the stuff they smoke may not be so green, according to the Seattle Times.
The bad news comes courtesy an April 2011 report by a scientist at Lawrence Berkeley National Laboratory. Here are the numbers: Growing enough marijuana for a single joint indoors produces 2 pounds of carbon dioxide, the same as running a 100-watt light bulb for 17 hours. Producing 2.2 pounds (1 kilogram) of Mary Jane is no different than driving across the country five times in a car that gets 44 miles to the gallon, at least as far as carbon emissions are concerned. Of course, growing marijuana outdoors in natural sunlight would sidestep these issues — perhaps famously sunny Colorado, which recently legalized recreational pot, can run that energy experiment.
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Stephanie Pappas is a contributing writer for Live Science, covering topics ranging from geoscience to archaeology to the human brain and behavior. She was previously a senior writer for Live Science but is now a freelancer based in Denver, Colorado, and regularly contributes to Scientific American and The Monitor, the monthly magazine of the American Psychological Association. Stephanie received a bachelor's degree in psychology from the University of South Carolina and a graduate certificate in science communication from the University of California, Santa Cruz.