A system for detecting a local phenomenon, the system includes an interface for receiving queries information from a system for retrieving art related media, and a processor, configured to: (a) create a first local popularity chart, wherein the creating of the first local popularity chart includes enumerating, for each geographic area of a group of sampled geographic areas, identical query strings of queries that are included in a group of queries; (b) create a first global popularity chart, wherein the creating of the first global popularity chart includes enumerating identical query strings of the queries that are included in the group of queries; and (c) select at least one query string in response to a scoring of the query string at the first local popularity chart and to a scoring of the query string at the first global popularity chart; wherein the group of queries includes queries which were queried during a first period of time.