The term «heat island» is used because warmer city air lies in a «sea» of cooler rural air. (climatechangefacts.info)
But a comparison of the congestion charges in London and Stockholm suggests the schemes only achieve this if they drive down the amount of nitrogen dioxide belched into city air by vehicles. (newscientist.com)
New York City's Clean Heat Program was launched in 2010 to eliminate the use of residual diesel fuel oils — diesel - based fuels that remain after gasoline and distillate fuels have been removed from crude — in residential buildings, in order to help address city air pollution levels that historically failed to meet the minimum criteria for federal Clean Air Act standards. (sciencedaily.com)