Font: http://www.citylab.com/tech/2015/06/mapping-your-citys-smells/394718/
So the scientists, led by researchers Daniele Quercia and Kate McLean, got to work.
First, they took local volunteers on a series of “smellwalks,” jaunts around seven global cities during which participants identified distinctive urban smells. From this exercise, the researchers created a comprehensive urban smell dictionary, including less pleasant odors (“exhaust,” “manure,” “trash,” “putrid,” and “vomit” among them) and downright lovely-sounding ones (“lavender,” “fruity,” “BBQ,” and “baked,” for example).
Then they turned to Big Data. Zooming in on just two cities—London and Barcelona—the researchers searched for their designated smell words (and their Spanish equivalents) in geotagged posts on Twitter, Flickr, and Instagram. In all, their sample included 17 million Flickr images, 436,000 Instagram posts, and 1.7 million tweets published and geotagged between 2010 and 2014.
Their results? Take a gander below. First up is Barcelona, with areas where social media users found the most emissions smells in red, and where they found the most nature smells in green.