The web giant envisages advertising based on the local weather conditions, detected by sensors in a mobile device. “When determining what ads to serve to end users, the environmental factors can be used independently or in combination with matching of keywords associated with the advertisements and keywords in user search queries,” said the patent, which was awarded by US authorities on Tuesday. “A web browser or search engine located at the user\'s site may obtain information on the environment (e.g. temperature, humidity, light, sound, air composition) from sensors. “Advertisers may specify that the ads are shown to users whose environmental conditions meet certain criteria.” The patent suggests that if temperature rises above a certain level Google could serve up advertising for air conditioning systems. Google also patented the idea of analysing the background noise when a user makes a call to target advertising. For instance, the system could detect if a user is at a concert and determine which by via their GPS location. It would then deliver advertising for albums, instruments, or audio equipment. Observers said the patent was reminiscent of Minority Report, in which Tom Cruise in besieged by highly target advertising on the streets of a dystopian city. “Not content with collecting vast amounts of information from your online activities, it seems Google are looking to start exploiting the offline space as well,” Gus Hosein of Privacy International told the BBC. “Patents like this may never come to fruition, but they force us to ask ourselves: how many aspects of our lives will advertisers try to exploit, and where will it end?” Google makes almost all its income from web ads targeted on the basis of what users type into search, the contents of the web pages they view and records of their interests.