Clouds Don't Cry: The Shape of Raindrops
by Daphne Thompson, on Apr 13, 2016 11:16:45 AM
When you draw a raindrop, what shape is it? Does it look like a teardrop? Clouds don't really cry. Raindrops are actually a pretty interesting shape.
If you have children, you have probably noticed that all their weather drawing have a tear shape for rain. Everywhere you look, you will find images of clouds raining tears. Clipart, clothing, jewelry, mugs, shower curtains, blankets, and the list goes on of weather tears. I'm not sure who the first person was to draw this shape for rain, but it has really caught on. It is nearly impossible to find an image with rain that looks different from this. There are really a lot of upset, sad clouds out there.
In reality, raindrops are a different shape due to gravity. They don't look like teardrops at all. Small raindrops are spherical. Bigger ones look like hamburger buns.
There are a lot of very tiny particles of dirt in the air. When moisture condenses on them, clouds begin to form. The water droplets in clouds are so tiny that they can float in air. However, as these droplets begin to collide, they form bigger droplets. Eventually, these drops are too big to stay afloat and they fall to Earth as rain.
Here you can see the stages of a raindrop as it grows:
1. The droplet is tiny. Air pushing up on it as it falls creates a spherical shape.
2. The raindrop has enlarged in size after bumping into others. Air pushing against it as it falls now causes it to look like a little hamburger bun.
3. The raindrop is getting pretty big now and having trouble keeping its shape. The air is now trying to split it apart. Raindrops much bigger than this rarely remain together.
4. The raindrop has become too large. As it falls, the air pushing on it breaks it apart in two. The process will begin again as the smaller ones continues to fall and collide with other drops.
A raindrop that falls into dry air will evaporate. Rain that doesn't reach the ground is known as virga. If a raindrop falls into air below freezing, it will become some sort of winter precipitation. This can vary from snow to sleet to freezing rain depending on the temperature of air it falls through. By the way, notice that even in this graphic the drops are the wrong shape. Apparently people don't like to draw hamburger buns falling from the sky!
On the other hand, there is a movie out there with hamburgers raining from the sky. Granted, it's not based on science, but they got the shape right!
So, one thing we have established here is that raindrops do not look like tears. Clouds don't cry... at least not real ones!