How can a cow pollute the environment? It’s all about gas. Right now, climate change is happening because we produce gases—mostly by burning fuels like oil and coal. Those gases are called greenhouse gases. They collect in Earth’s atmosphere and trap the sun’s heat close to the planet’s surface. This is called the greenhouse effect.
Cows contribute to the problem in two ways. First, they burp a lot—and that is not a joke. When cows eat grass, their stomachs produce a gas called methane. A typical cow makes about 220 pounds of methane a year.
When cows burp, all that gas goes into the atmosphere. It adds to the greenhouse effect.
That’s not the only way cows add to climate change. It takes a lot of grass to feed a herd of cows. To create grasslands, forests must be cut down. Every year, farmers clear more than 10 million acres worldwide. That’s an area bigger than the state of Maryland. The trees in those forests contain a gas called carbon dioxide. When they are cut down, that gas is released into the atmosphere.