Global methane and ethane emissions from oil production from 1980 to 2012 were far higher than previous estimates show, according to a new study which for the first time takes into account different production management systems and geological conditions around the world.

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Global methane and ethane emissions from oil production from 1980 to 2012 were far higher than previous estimates show, according to a new study which for the first time takes into account different production management systems and geological conditions around the world.