A carbon footprint is a simple way to express that impact. The “size” of your carbon footprint depends on multiple factors. The primary one is the amount of greenhouse gas emissions released into the atmosphere by a given activity.

People, products and entire industries have carbon footprints. Your personal footprint includes emissions from a variety of sources — your daily commute, the food you eat, the clothes you buy, everything you throw away ... and more. The larger your footprint, the heavier the strain on the environment.

To halt climate breakdown and avoid its worst impacts, we need to do two things: shift to a low-carbon economy and protect our best natural allies in the fight against climate change — forests, grasslands, mangroves and tidal marshes, which stash away large quantities of carbon.

Drastically cutting greenhouse gas emissions will require, everyone — from individuals to industries to countries — to vastly reduce their carbon footprint. Here’s the information and practical steps you’ll need to get started.