Relying more on natural gas and less on coal would do “little” to slow down global warming despite far less carbon dioxide being released, a new study found.
Replacing 50 percent of coal use with natural gas use would cause global temperatures to increase by 0.1 degree Celsius over the next 40 years if no other action were taken, according to the study, which was performed with computer simulations. The switch — at best — could cause temperatures to drop 0.2 – 0.3 degrees Celsius by 2100 if no methane leaked into the atmosphere, according to the study.
Under current energy trends, temperatures are predicted to rise 5.4 degrees Fahrenheit (or about 3 degrees Celsius), according to the study.
“Relying more on natural gas would reduce emissions of carbon dioxide, but it would do little to help solve the climate problem,” Tom Wigley, senior research associate at the National Center for Atmospheric Research and the study’s main author, said in a statement. “It would be many decades before it would slow down global warming at all, and even then it would just be making a difference around the edges.”
Wigley notes recent studies have reached conflicting conclusions about how much natural gas use contributes to global warming. A recent Cornell University study found that natural gas was more harmful to the environment than coal because of methane leaks during the hydraulic fracking process.
Those leaks, according to the study, are more dangerous than the carbon dioxide emissions from coal-burning power plants.
Wigley’s study attempts to account for those methane leaks as well as the slight cooling effect that occurs from sulfur dioxide emissions during coal burning.
The 0.2-0.3-degree decrease from natural gas use — if things remained as they are — would occur by 2100 only if no methane was released into the atmosphere, according to the study. If methane leaks can be reduced to just 2 percent, the decrease would be 0.2 degrees. If methane leaks occur at 10 percent, a decrease in the rate of global warming wouldn’t occur until 2140, the study finds.
“Using climate amelioration as an argument for the transition [from coal to natural gas] is, at best, a very weak argument,” Wigley writes in the study, which will appear in the journal Climatic Change Letters.
Any decrease wouldn’t likely happen until temperatures increased 0.1 degrees Celsius, the study finds.