(1) It has been claimed that replacing coal-fired power stations with gas-fired power stations will result in benefits for the climate.
(2) When natural gas (methane) is burned, it produces only about half as much carbon dioxide as coal does for the same amount of energy produced.
(3) However, some gas always leaks from pipelines, and methane is itself a potent greenhouse gas that can cause climate warming.
(4) On the other hand, coal-burning emits tiny dust particles (aerosols), and these have a cooling effect on the climate.
(5) The National Center for Atmospheric Research is a leading US research centre funded by the National Science Foundation.
(6) Scientists there have been working to predict what the net effect will be, given that atmospheric carbon dioxide is very long-lasting.
(7) Their most recent study suggests that it would take more than 100 years for a switch from coal to gas to produce any significant slowing in the rate of global warming.
(8) So changing from coal to gas may not result in immediate benefits for the climate.