Aims to slow down global temperature rise by 0.5°C. The United States will lead a global campaign to reduce short-lived pollutants that aggravate global warming. In an announcement made on February 16, secretary of state Hillary Clinton announced the formation of a new coalition called Climate and Clean Air Coalition that will target non-Co2 pollutants, including methane, hydrofluorocarbons and black carbon. She made the announcement in the presence of ministers from four member countries of the coalition.