Methane is a greenhouse gas that is extremely bad because it reflects roughly 30 more heat than CO2 and is 80 times more harmful than CO2 over the course of 20 years. 

Cows (those friendly fellows) account for 45% of methane emissions by releasing methane in a few ways, such as burping!!

Why do cows release methane?

The reason cows release methane is because there are microbes in a cow's stomach, and microbes need carbon, so when the cow its it's feed, the microbes take the carbon they need, and the result a few days later is methane coming out of the cow body stomach by burps or farts!

Perhaps we need to reduce the number of cattle we breed and in turn eat more vegetables?