 So now we can move on to how this actually works in our atmosphere. Now to start with, again, we've got the ground, the sky, and a thermometer. I have actually set the greenhouse gas concentration down to zero to start with. And if I play, I see very much the same sort of simulation as what I saw when I had no glass. All the infrared photons escape back out into space. Now you'll notice the temperature changes a little bit depending on how much heats and there's a little bit of fluctuation in there. But it's staying a nice minus two minus three degrees Fahrenheit, not very warm. As I increase the amount of greenhouse gas, you'll start to see that some of the infrared photons are being directed back down rather than being able to escape. And again, some of them do escape outwards. So that has a warming effect on the ground. If I continue to increase the amount of greenhouse gases, more and more of the infrared photons end up being directed back down to the ground, causing the ground to warm up. As I increase even further, we see that a large amount of the infrared photons are being directed back down to the ground. So the ground is being heated by the initial visible light from the sun and then reheated by all of the infrared photons that are being redirected back down to the ground. And it causes the temperature to increase significantly. If I take it all the way up to the maximum that the simulation allows, some infrared photons still get out. But for the most part, they're being bounced back down to the ground. The ground is heating up and it gets very hot. Now this is actually a representation of what happens on Venus where we have a heavy carbon dioxide saturated atmosphere and the ground temperature is significantly hotter than you would expect for the planet for the distance it is from the sun. Luckily our planet's not got quite that much carbon dioxide. If we go to today's values, it's a more moderate range. But we want to make sure that we don't continue to increase the amount of greenhouse gases in our atmosphere. If we're able to reduce the amount of greenhouse gases, then slowly over time we would expect the temperature to be able to cool off a little bit.