"Study: Some Natural Gas Threatens Climate More Than Coal"

"Extracting natural gas from shale formations using hydraulic fracturing generates more greenhouse-gas emissions than burning coal, according to a new study that drew immediate attacks from oil and gas interests already facing pressure from lawmakers and regulators worried about the environmental effects of shale-gas development.

The study, conducted by professors at Cornell University, found that natural gas obtained from shale formations using a process known as 'hydraulic fracturing' releases large amounts of methane. When methane emissions are taken into account, natural gas from these shale formations produces more greenhouse gases than coal and coal-fired electricity generation over a 20-year time horizon, the study said.

Until now, Democrats on Capitol Hill and some environmental groups have looked to natural gas as a 'bridge fuel' that could help the country make the transition from carbon-heavy fossil fuels such as coal to cleaner sources of energy."

Tennille Tracy reports for the Wall St. Journal April 11, 2011.