Many theories suggest that farts contribute to global warming. Methane, a natural gas found in farts, absorbs energy from the sun that normally would be released into space. Absorbing this energy makes the earth warmer, and the more greenhouse gases there are in the atmosphere, the warmer the earth's temperature.
According to The Food and Agriculture Organization of the United Nations, burps and farts from livestock (especially cows) are responsible for 18% of the world's greenhouse gas problem.