(Flickr: creative commons by phatman)
Thunder 101
It is the middle of the night and you are a child lying awake with blankets pulled tightly around you. The loud din of a rainstorm pours on the roof overhead. A shockingly bright flash of light illuminates your room for a split second, leaving behind ghostly images burned into your eyes. You slowly begin to count, “One, two, three, four…” and then a deep powerful rumbling shakes your house, your bed, your bones, as waves of sound descend from the night air and push you deeper under the covers.
The magnitude of weather phenomenon compared to that of a single human is awe inspiring and the force so mighty, that it is unsurprising the gods have often been held responsible for such events. Thunderstorms have been the source of speculation, exploration, and study for millennia. The blinding flash of lightning is the harbinger of the crackling thunder to come, as the speed of light waves outpaces the sound waves. To understand thunder, one must first grasp the physical aspects of lightning and sound.
Lightning is an explosive release of tension from imbalanced electromagnetic pressures created in storm clouds. Air currents rub against each other, creating friction which builds an electric charge, kind of like the friction charge built when you scoot your socked feet along a thick carpet. Water in the clouds drops downward, bringing with it charged electrons, which creates an imbalance with the rest of the cloud above. When the difference between the two, or the earth below, becomes too intense, lightning bolts manifest.
Sound, simply put, is physical vibrations of specific frequencies that your ears detect. This is most notable when those pesky neighbors blast their stereos until your bookshelves rattle or when you place a drink on a speaker at your favorite concert and mini waves of liquid slosh around in your glass.
When a boiling pot of water rattles a loose lid, it demonstrates the pressure of the heated steam pushing to expand outward. A lightning bolt strikes for just a fraction of a second, but its plasma scorches the air at temperatures five times hotter than the surface of our sun. This extraordinary shift in temperature causes the heated air to expand explosively against the cooler air next to it, creating intense vibrations in the sky that rumble ferociously out in all directions, becoming what is commonly referred to as… thunder.
