In reality, gas fracking involves the release of large amounts of methane into the atmosphere in the form of 'fugitive emissions'. Methane is an extremely powerful greenhouse gas -86 times owrse for climate change than carbon dioxide is over 20 years. 

In fact recent research is confirming that gas from fracking is likely worse for the climate than coal. The good news is we don'e need either - renewables and energy efficiency are repidly removing the need for any fossil fuels.