Introducing John Tyndall. In the 1860s Tyndall investigated methane and CO2 and water vapor to see whether any of them block infrared radiation , and they all do. But methane and water vapor don't stick around in the atmosphere for long.
You have ultraviolet radiation from these lights. You have infrared radiation that you guys are beaming out, because we're all warm bodies and when you're a warm body at about 98 degrees Fahrenheit, you're beaming infrared radiation .
You have infrared radiation that you guys are beaming out, because we're all warm bodies and when you're a warm body at about 98 degrees Fahrenheit, you're beaming infrared radiation . But all these things you cannot see.
And it's not unsafe. That's conduction. This is radiant heat-- infrared radiation .
is relatively transparent to the sun's rays and hits the surface, the surface warms up. And then, the surface then emits infrared radiation . In fact, everybody in this room is emitting radiation. Anything that is above absolute zero emits radiation, okay? And so you're emitting infrared, and so is the earth. The earth emits radiation, okay? Now, if there was no atmosphere, that radiation would go happily out into space, and then you'd have
Visible light from the sun meets little resistance inbound, because the size of the wavelengths is hella tight. But then when it hits the Earth, it emits infrared radiation with longer waves and that you're trapped and bounce back when they try to escape on their way back up into space. And climate deniers today, from Ted Cruz to Rand Paul to Bobby Jindal, might say, bounce back off of what?
the last several decades, and no matter what we do, it's going to pretty decrease quite a bit during this upcoming century, okay? So CO2 is going up. Now, greenhouse gases help keep us warm because they act like a blanket. They actually--what they do is absorb and send back down infrared radiation . Now, I'll talk about that in a second. But greenhouse gases are going up. Do you know what the number one greenhouse is? It's not CO2. It's water vapor. Water vapor is a very potent greenhouse gas. So anyway, the greenhouse, this greenhouse
you're emitting infrared, and so is the earth. The earth emits radiation, okay? Now, if there was no atmosphere, that radiation would go happily out into space, and then you'd have a balance between what's coming in and what's going out. Well, the atmosphere have gases, like CO2, and methane and other gases that absorb some of the infrared radiation and sends it back down to earth. It also emits some out to space. So, instead of the stuff escaping, some of it is absorbed and sent back down. That acts to warm us up. It's like