Natural greenhouse effect

Hello! Today we are going to find out more about the greenhouse effect. Without this effect, the temperature at the surface of our planet would be -18°C. Although humans and their activities are responsible for the acceleration of this greenhouse effect— we talk about it a lot in connection with global warming— it is essential to life on Earth. Want to understand how it works? Here's an experiment that will answer all your questions. For this experiment you need a small glass bowl, two small jars of the same capacity, a little cold water, and a thermometer. Pour the same amount of water into each jar. Then cover one of the jars with a bowl. All that's left to do is to place everything in the sun and wait for an hour. What will happen? Will the temperature of the water be the same in both jars, or will the water be warmer in one of them? But which one?

Let's take the temperature in the two jars.

In the first, the water's barely 30 degrees. And in the second, under the salad bowl— [NOISE] This time the temperature is at least 37 degrees. The water in the glass under the salad bowl is warmer. This is because the glass has trapped the heat coming from the sun. Light energy from the sun is made up of infrared, visible light, right through to ultraviolet light. Only the visible part passes through the glass of the salad bowl. This light energy, partly absorbed by the glass of water, is re-emitted in the form of infrared light. The glass will trap the infrareds. They accumulate in the bowl and cause the water to heat up. The air trapped in the bowl, which is not renewed, will also heat up more and more. Contributing to the rise in temperature of the water under the glass bowl. In this way, the salad bowl placed on the glass of water behaves in the same way as a gardener's greenhouse or the Earth's atmosphere. It traps the heat and prevents it from dissipating. This is known as the greenhouse effect. Thanks to this effect, the average temperature on Earth is 15°C. You can repeat the experiment yourselves on a sunny day. See you soon!