ELI5 Burping - how loud was the world loudest burp?

What exactly causes a burp, and why does it happen? How do cows and their burps play a role in greenhouse gas emissions? When they say  “livestock are responsible for burping the methane equivalent of 3.1 gigatonnes of carbon dioxide into the atmosphere annually" what does the methane equivalent of CO2 mean? Where was the world’s loudest burp recorded? ... we explain like I'm five Thank you to the r/explainlikeimfive community and in particular the following users whose questions and comments formed the basis of this discussion: yeetonem, purehatred89, insane_eraser, shakeshuka, mmmmmmbacon12345, bishopdamage, creasedjaw and rudimentarysasquatch To the ELI5 community that has supported us so far, thanks for all your feedback and comments. Join us on Twitter: https://www.twitter.com/eli5ThePodcast/ or send us an e-mail: [email protected]