Misconceptions about Weather - mental_floss on YouTube (Ep. 31)

Hi, I'm Ellie and this is Mental Floss on YouTube

Today I'm going to talk about some misconceptions about the weather. Misconception number one, lightning comes from the cloud down

Lightning comes from both clouds and the ground, but when we look at lightning, what we're seeing actually came from the ground

According to the National Severe Storms Laboratory, a typical cloud to ground flash lowers a path of negative electricity

that we cannot see towards the ground in a series of spurts. Objects on the ground generally have a positive charge

Since opposites attract, an upward streamer is sent out from the object about to be struck

When these two paths meet, a return stroke zips back up to the sky. It's the return stroke that produces the visible flash, but it all happens so fast

in about one millionth of a second, so the human eye doesn't see the actual formation

of the stroke. And now that you know how lightning works, misconception number two

Lightning strikes the tallest object. Most likely it will strike the tallest object nearby

Because lightning is coming from both the ground and the sky, it's ideal to have less distance between those two things, which is why buildings and towers get struck the most

But once the lightning coming from the sky gets closer to the ground it not able to make distinctions between objects and find the tallest one It will be most attracted to tallest objects but might hit the ground or even a person instead Misconception number three it can be too cold to snow For it

to snow, there's no requirement that it must be cold, but not too cold. The only necessity

is water vapor in the air, but there probably will be less snow if it's very cold, because

the air has less water vapor in it. In Antarctica, snow has been recorded in temperatures as

low as negative 70 degrees Fahrenheit. Misconception number four, a tsunami means a single giant

wave. It's worth mentioning that this is probably the definition you'll see if you look up tsunami

in the dictionary, but a tsunami is considered any sudden displacement of a large amount of water

Sometimes that means a bunch of smaller waves rather than one huge one, and those can be just

as devastating. Misconception number five, the polar vortex is new. Though we hear the term a lot

in the news lately, there's nothing new about the polar vortex, okay? The phrase dates back to 1853

when it was published in the magazine Household Words. John Capper wrote an article about weather

and named the currents around the North and South Poles the Great Polar Vortex

We have a similar meaning for the term nowadays. It refers to the two cyclones that rotate around Earth's two poles

Every once in a while the polar vortex may shift and start affecting our weather like it did in January 2014 Something similar happened in the late 1970s Misconception number six freezing rain means the raindrops are frozen Actually the reason it called freezing rain is because the drops freeze when they hit a surface

Basically, they fall through a lot of warmer air before they reach the really cold ground

This causes instantaneous freezing when a drop hits a surface, like the ground or a car

And this is different from sleet, which freezes as it falls through the air. Misconception at number seven, you can tell how far away a storm is by counting the seconds

between when you see lightning and hear thunder. Okay, so this is technically true, but most people have the details kind of wrong

People usually believe that the number of seconds between the lightning and thunder is the number of miles between you and the lightning

In fact, the lightning is even closer than that. The seconds counted needed to be divided by five, and that is the actual distance

So, if you count ten seconds between lightning and thunder, the lightning is a mere two miles away from you. Sleep tight

Misconception at number eight, tornadoes don't go through mountains and cities. It's rare for one to hit a city, but it actually does happen

For example, a tornado hit Oklahoma City in 1999, and a few years later, in 2007, one

went through Atlanta, Georgia. It doesn't happen often because cities take up less space on land compared to rural areas

so statistically, tornadoes are more likely to hit the country. As for mountains tornadoes have been recorded in peaks as high as 10 feet They been found in the Rocky Mountains the Appalachian Mountains and plenty of other mountain ranges Misconception number nine you safe in a car during a tornado So people typically say this because cars can technically go faster than tornadoes

so outrunning one is possible, if not horribly terrifying. But if the tornado is strong

it can potentially hurl a car through the air. So experts suggest that you take shelter in a house

or basement instead of your car. In fact, the National Weather Service recommends that if

you're near a tornado and can't be home, you should abandon your car and take shelter in a

ditch or low area. Which brings me to misconception number 10. Use a highway overpass as a storm shield

There have been some widely publicized cases of people taking cover from tornadoes and storms

underneath highway overpasses and being totally fine. But these were the exception, not the rule

And in fact, in some of these cases, the news stories left out the fact that the tornadoes

didn't even directly hit that area. Many people have died doing this and meteorologists now believe

that it might be the most dangerous place to be during a tornado. If you have a topic for an

upcoming misconceptions episode that you would like to see, leave it in the comments. And thank you for watching Misconceptions on Mental Floss on YouTube, which is made with the help of all of

these wonderful people. And I will see you next week. Goodbye