I’m many things — Husband, father, brother, son, mediocre softball player — but none of those matter quite as much with people as when they learn that I am a meteorologist. After my fake laughter subsides from the ever clever quip about getting paid to be wrong,* I usually am bombarded with all sorts of questions about the atmosphere. Nothing turns grown adults into inquisitive little kids than learning about how tornadoes form, or why it rains. And few things excites little kids more than the weather.
Many of us remember the elaborate explanations we were given as kids by well meaning relatives and teachers when we asked about the weather. What’s thunder? It’s God bowling. Why does it rain? Because the clouds cry. These are cute, but I think giving kids the science is way more fun.
Every winter I field tons of questions about snow from my young nieces and nephews, every spring the conversation turns to thunderstorms, while summer has hurricanes on lock down. The fall? Well we talk about candy and Halloween. We all really like candy and Halloween.
But meteorologists shouldn’t hog all the atmospheric glory! But how are you supposed to explain complex atmospheric phenomena like rain, wind and thunder to a toddler? Here are some simple answers to often asked atmospheric questions (from adults to toddlers alike).
What is thunder and why do we see lightning always first?
First, thunder is not God bowling, or laughing or sneezing or whatever other bodily function or hobby God has. Thunder is just a sound caused by lightning. You can’t have one without the other.
Lightning happens in a similar manner to if you run your socks on a carpet on a dry winter day and then touch your sibling to shock them (or sliding down a plastic slide on a warm summer day). Similar phenomenon, except instead of the electricity traveling from you to your sibling, it travels from cloud to cloud. When lightning strikes from a thunderstorm, the bolt can get up to 54,000°F, five times hotter than the sun.
As the bolt of lightning travels through the air, it heats the air around it. The now heated air does what hot things generally do and expands or gets bigger. This is why hot air balloons use hot air to float. A cold air balloon is just a deflated balloon on the ground. This quickly expanding air causes all those air molecules to bump into other air molecules farther from the bolt. We hear this collision as a sound wave or thunder.
You can also think of it this way: Imagine along the path of the lightning bolt there are an endless amount of balloons. As the lightning moves through them, they each expand past their limits and then break making a sound.
The closer you are to the lightning the more CRACK! SNAP! the thunder will sound. The farther away you are you may instead hear that unmistakable rumble of thunder which is just that sound wave bumping and bouncing off of the ground, buildings, trees or anything in its path until it gets to your ear.
So no God is not causing thunder by bowling, it’s all a matter of really hot air (which is more of a human trait).
But we see the lightning way before we hear thunder. Why?
Thunder is simply slower. If this was a foot race, lightning would be crossing the finish line way before thunder even realized the race had started. Thunder is the tortoise, and lightning is the hare. Our eyes see the lightning first, then our ears have to wait for thunder to mosey on by at its own slower pace.
Remember though, if you see lightning or hear thunder, it’s best not to get a closer look. GO INSIDE!
What is rain and why does it fall?
We’ve covered the lightning and thunder, now we need to talk about rain. The clouds you see in the air are actually made up of tiny liquid water droplets. They are so tiny and so light that they float in the air, like how dust seems to levitate in a sunbeam shining through a window. But these water droplets in clouds don’t stay put. They can move around and bump into each other. And water droplets stick together, slowly getting bigger and heavier. Eventually they get so big, they can no longer float and begin to fall to the ground as rain. The next time it’s raining outside take a look at the water on a windowpane. Smaller drops begin to slowly drip down the window running into other drops along the way. As the drop gets bigger it drips faster down the glass, just like how raindrops form.
What is wind?
Lightning/thunder – check. Rain – check. Next up, the wind! In theory this one is simple. We all breathe air. Wind is just moving air.
Next time you are outside, run really fast by another person (OK, let’s be honest, the next time you’re outside and someone runs past you really fast). They likely will feel a wind caused by you moving the air in your path.
The cool thing about air is that it really likes things to be equal. If air was given one cookie to share with a friend, air would split that cookie perfectly in half. If air was splitting a room full of people into groups, those groups would all have the same number of people. In our atmosphere, air’s quest to make things equal is called wind. Low pressure systems (storms!) just mean there is less air in that location, so winds swirl counterclockwise in towards the center of the low pressure. High pressure systems (sunny days with no clouds!) have too much air. Winds swirl clockwise away from the high pressure towards the nearest low pressure. The bigger the difference between the high pressure and low pressure means the stronger the wind to move all that air to the low pressure.
We just covered a few basics that hopefully will demystify the weather and give you something to think about the next time you head outside. But there is plenty more to learn. Have any questions? You can find me on twitter @TDiLiberto, as long as you don’t ask me why I’m wrong all the time.
*As an aside, on average your weather forecast is likely more accurate than a doctor’s diagnosis. A 2000 study of autopsies from the Mayo Clinic comparing clinical diagnoses with post-mortem diagnoses found that in 26% of cases a major diagnoses was missed. So give your humble meteorologist a break.