Hey, Matt: When we watch scary movies, my mom screams a lot but my dad doesn’t. When we go out to a movie, ladies scream but the men don’t. I think scary movies are pretty scary for me. I put my hand over my mouth so I don’t make so much noise. Sometimes my father laughs when we scream. I wonder why this happens. Do guys not get scared at vampire movies and stuff like that? — Chelsee, San Diego

Matt: Why do people close their eyes when they hear loud noises? It’s like a reflex. There’s some sort of boom and you just have to blink. Why? — The Eye, Boomtown

Photo by Rick Geary

It’s “like a reflex” because that’s what it is. Startle reflex. Acoustic startle reflex, to be specific. Especially likely if you’re the wound-up sort; much less likely if you’ve had a drink or three. And that’s according to the science guys; I didn’t just make that up. But of course the science guys had to make up some sort of explanation for the blink results they get, so here’s what they’ve come up with: loud noises often accompany danger, and when we sense danger we instinctively react to protect ourselves. What needs protecting a lot? Well, you might not agree, but the science guys say we react to the danger signal by protecting our eyes. The best we can do on such short notice is to close our eyelids.

And if it seems strange that the science guys have wasted their time studying blinks, well, it’s critical to national security that movie guys study our movie-going brains. So, everybody knows that girls are going to scream away during the scary parts. Females are more expressive (in general) than males, especially in the realm of emotions, so it’s no big deal. Guys, on the other hand, aren’t encouraged to wave their feelings around and call attention to themselves. So far, no big secrets. But what the movie guys found out when they finally tested the guys and the gals during scary movies is that men do get scared and do have the same emotional reactions as women, they’re just not allowed to express them. No screaming allowed.

Matthew: Is the United States the only country that has big tornadoes? You never hear about a tornado hitting Germany or Australia. Why do we have so many of them? — Anonymous, via email

You never hear about tornadoes in Germany or Australia, but they hear about them in Germany and Australia. Tornadoes happen all around the globe; it just happens that the U.S. has several special things going for it. First of all, we’re big. Anything that happens between the Atlantic, the Pacific, Mexico, and Canada “happens in the U.S.” Superimpose us on Europe and we’d cover lots of countries. That’s pretty obvious, but it does address part of your question. The other thing we have going for us is the fact that our southern parts are warm and tropical and our northern parts are frigid. And we don’t have any east-west mountain ranges that interfere with weather patterns. The majority of our tornadoes happen in the flat corridor between the Rockies and the Appalachians, though all 50 states have recorded tornadoes.

Yes, the U.S. has more tornadoes than any other country, and, yes, ours are more severe than most others. We’ve averaged about 1200 a year for the past few decades. The weather wizards understand some of the basics about tornado generation, but like other meteorological events, they’re complex and haven’t been studied in detail for long. Even historical records are suspect, since we haven’t had consistent definitions for tornado-related events, so we can’t always tell exactly what happened. One thing our recent tornado swarms have shown us is how little we really know about the things.

Tornadoes start off with thunderstorms. Thunderstorms usually begin with low-level, warm, moist air topped off with an incoming layer of cold air. The two fronts are spinning in opposite directions, set up a shear, and if all details are in place, a tightly spinning (counterclockwise, in our hemisphere) tornado vortex might drop down. When it connects storm cloud and ground, you have a tornado. Simplistically, think of our warm, muggy Gulf of Mexico climate and the potentially frigid Arctic climate that meet one another over the central U.S. If the jet stream drops the cold down far enough, we might get super-cell thunderstorms and eventually tornadoes. This year the temperature gradients between northern and southern weather fronts have been more extreme than usual, which the National Weather Service says accounts for the large number of tornadoes we’ve had. We’ll have more of them in the spring and fall, when temperatures are more variable. And they’re more likely to happen between mid-afternoon and sunset, when the sun’s warmed the Earth. So, we do hog most of the world’s tornadoes, unfortunately. But keep your eye on the sky in England or the Netherlands. They know tornadoes, too.