Colorado State University

We’ve all heard talk about greenhouse gases—the gases in the earth’s atmosphere that help keep the earth warm. What’s so special about these gases that gives them this awesome power?

The answer is simple: Greenhouse gases absorb and emit thermal radiation. And that’s what this video shows. We use a regular camera and a thermal camera to record a scene. The thermal camera detects thermal radiation, so if the gas doesn’t emit or absorb, there is not much to see! Hot air looks like, well, nothing.

But for water vapor and carbon dioxide, it’s a different story! And that’s a big part of the story of why the earth is the hospitable place we’ve come to know and love. The greenhouse effect is a good thing. Now, it’s possible to have too much of a good thing… Which is another story we’ll tell later!