Foul or musty? German city of Ulm seeks volunteers to sniff out mystery odours

"The State Agency for the Environment Baden‑Württemberg (LUBW) has launched a year‑long project inviting locals to report strange smells via a smartphone app, Ortelium. Experts hope the technology will be able to detect patterns where human memory and municipal guesswork have so far fallen short. The app links each smell report with meteorological data, allowing researchers to track how odour‑laden air pockets drift through the city."

"As part of the project, volunteers are being asked to log any noticeable smell, whether pleasant or unpleasant, whose origin they cannot identify over the course of the year. To help them recognise what they should be recording, participants are initially given a 'scent stick' and asked to assign it to a category - reportedly including "musty", "foul" and "like cat urine"."

"Why Ulm? Ulm - birthplace of Albert Einstein - may be picturesque, with its soaring Minster tower and riverside setting, but it's also a city where odour complaints crop up with surprising regularity. As a LUBW spokesperson explained, "in recent years, the city has repeatedly received odour complaints, some of which could not be traced to a specific source". From the agency's perspective, this makes Ulm an ideal testing ground for a new approach to odour management."

Ulm residents are being recruited for a year‑long citizen science project to report unexplained smells via the Ortelium smartphone app operated by the State Agency for the Environment Baden‑Württemberg (LUBW). Each smell report is automatically linked to meteorological data to enable mapping of odour-laden air pockets and their drift patterns. Participants are instructed to log any noticeable smell of unknown origin and are given a 'scent stick' to help classify smells into categories such as 'musty', 'foul' and 'like cat urine'. The city sees frequent odour complaints, and the project aims to identify potential sources, reveal travel distances of odours, and assess the app's performance for odour management.

Read at The Local Germany