It can be seen in thunderstorms, hurricanes, snowstorms, and even volcanic eruptions. Lightning is a natural atmospheric phenomenon caused by the difference between positive and negative charges. When enough opposite charge builds up, the air can no longer insulate the charges, resulting in a rapid discharge of electricity. Martin Fisher, Executive Director at Science Central, uses the Van der Graaf generator at Science Central to demonstrate this in a safer way.
“What’s going on up in the sky with air, with lightning is you have all of these air particles, water particles, dust particles, that are rubbing up against each other. Two different objects rub up against each other and it builds up a static charge. Static electricity – and that’s what lightning is.”
Lightning and thunder go hand-in-hand. You can’t have thunder without lightning. A bolt of lightning heats the air around it to as high as 50,000 degrees in just a few millionths of a second. That’s about 5 times hotter than the surface of the sun.
Fisher adds, “Thunder is this incredibly fast expansion and contraction of air. And it’s because the lightning is so hot. It heats up the air, moves out, comes crashing back in – we hear a sound. We can’t really see that it’s hot, but this machine does show that the spark is hot. It’s warming up the air, it’s rising up and bringing the spark with it.”
Lightning helps the earth maintain electrical balance and makes ozone-producing chemicals. Without thunderstorms and lightning, the earth-atmosphere electrical balance would be gone in about 5 minutes.
Most lightning is cloud-to-cloud, but lightning strikes the ground – or cloud to ground – an average of 20 million times each year in the U.S. according to the National Weather Service. The chance of you being struck by lightning in your lifetime are about 1 in 13,000.
When it comes to lightning safety the first thing to remember is “when thunder roars, go indoors.” Find a sturdy building or a vehicle as fast as you can. If you are stuck outdoors, avoid open fields, you don’t want to be the tallest object in the area…lightning tends to strike the taller objects so also avoid shelter near tall trees, towers or utility poles.
Since lightning is electricity you will also want to make sure you are away from any metal fences or wires. Inside of your home you will want to try and avoid using anything that is plugged into the wall, such as corded phones.
What if lightning strikes your home? The biggest danger lightning poses to a house is fire. It is most common for lightning to start a fire in the attic or roof of a house. You may smell burning without seeing the fire, as the insolation in many attics may delay the flames. If that’s the case, call the local fire department to make them aware of it.
A single lightning bolt can carry up to 1 billion volts and billions of watts of electricity.
That’s why it is incredibly dangerous to be outdoors during a thunderstorm. If there is a severe thunderstorm heading to your location you may hear the storm sirens. We will have more about those tomorrow night at 6 when Severe Weather Week continues.
And don’t forget, we have a bunch of links to get you prepared for the storm in the weather section on wane-dot-com