Jasmin from Lucerne wants to know from Bernie and Lexi:

Why does it actually rain?

Bernie watching an airplane in the sky that is flying through the rain

Bernie: "What a great question, dear Jasmin! For instance, the weather is quite important for pilots. That's why they check what the weather is like en route before every flight. So they know exactly what to expect. By the way, rain doesn't affect an airplane at all. However, in heavy rain the pilots have to take extra care during take-off and landing, because it can be slippery."

Lexi: "But let's get back to your question, Jasmin: As I am sure you know, rain comes from the clouds. They may look like floating cotton wool balls, but they actually consist of water drops or ice crystals.

The water originates from our rivers, lakes and of course from the sea. When the sun shines, the water evaporates - that means it heats up and turns into steam, which rises upwards together with warm air."

Lexi pointing to an airplane that is braking on the runway in the rain

Bernie: "Perhaps you have already noticed when flying that small ice crystals form on the windows. This is because the higher up one is, the colder it gets. That's why the water vapour also cools down as it rises.

The steam turns into small drops again and many, fine tiny little drops together form the clouds. When it gets even colder, the little drops flow together, which in turn makes them so big and heavy that they fall down: In other words, it rains."

Lexi: "Do you know what I think is really cool, Bernie? The rain ends back up in our rivers, lakes and the sea. Which means it can evaporate again, rise upwards, turn into clouds and subsequently rain again: So, it's an endless rain cycle! The next time you take off with SWISS, you can pay precise attention to what happens when you fly through the clouds, Jasmin."