For some time, fracking has had a reputation for curbing global warming since burning gas emits half as much carbon dioxide as the same amount of coal. The numbers associated with fracking looked good, too. After initially embracing fracking in the US, CO2 emissions have seemingly fallen.
However, climate scientists are cautioning that this is all an illusion. A recent study by Tom Wigley of the National Center for Atmospheric Research in Boulder, Colorado declares that replacing coal with gas actually raises rather than decreases the rate of warming for many decades because it involves methane and not CO2.
Fracking involves pumping massive amounts of water at very high speeds into shale beds deep underground in order to release trapped natural gas. However, this technique also releases methane, which then leaks into the atmosphere. Methane is far more damaging than CO2. Fracking experts have realized that long after fracking ends at a site, the methane may not stop leaking when the fracking wells are sealed.
Wigley posits that switching from coal to gas might only bring benefits during this century if leakage rates get below 2%. If rates are at 10% – the high end of current US estimates – the gas would deliver extra warming until the mid-22nd century.