Cow flatulence (farts) create methane. Methane is a greenhouse gas like carbon dioxide (CO2). But the negative effect on the climate of Methane is 23 times higher than the effect of CO2. Therefore the release of about 100 kg Methane per year for each cow is equivalent to about 2'300 kg CO2 per year. Simply eating less beef can create a smaller market for it, and make a positive impact on our climate as a result.