The actual breakdown process is still poorly understood. The air breakdown creates ions and free electrons that travel down the conducting channel. This current flow temporarily equalizes the charged regions in the atmosphere until the opposite charges build up again. Lightning from thunderstorms begins in a strong electric field between opposite charges within the storm cloud, and can stay completely within the cloud intra-cloud lightning when the charge regions are similar strength balanced or can reach the ground cloud-to-ground lightning when one of the regions is much stronger than the other unbalanced.
Lightning is one of the oldest observed natural phenomena on earth. It can be seen in volcanic eruptions, extremely intense forest fires pyrocumulonimbus clouds , surface nuclear detonations, heavy snowstorms, in large hurricanes, and obviously, thunderstorms.
Thunder is the sound caused by a nearby flash of lightning and can be heard for a distance of only about 10 miles from the lightning strike. The sound of thunder should serve as a warning to anyone outside that they are within striking distance of the storm and need to get to a safe place immediately!
Thunder is created when lightning passes through the air. The lightning discharge heats the air rapidly and causes it to expand. The temperature of the air in the lightning channel may reach as high as 50, degrees Fahrenheit, 5 times hotter than the surface of the sun. Researchers have been trying to answer this question for decades. Vertically, the extent of a flash is limited by the height of a storm cloud, or the distance from the ground to its pinnacle — which is about 12 miles 20 km at its highest.
But horizontally, an extensive cloud system provides much more room to play with. Back in , a meteorologist named Myron Ligda demonstrated this when he used radar to detect the longest lightning flash anyone had ever recorded at that point: a bolt that spanned 60 miles km.
Related: Images of Nature's Biggest Storms. Then in , researchers broke the record by identifying a flash over the state of Oklahoma that measured miles km long. The recent study by MacGorman and his colleagues knocked that number out of the park. The light emitted by this flash was so strong that it illuminated a ground area of 26, square miles 67, square kilometers , the researchers calculated. But even that flash has now been surpassed: Another recent study in the journal JGR Atmospheres described a flash spanning miles km.
Such megaflashes are rare. But now that we have the technology to detect them, we're finding them more frequently.
We take a look at ten interesting facts that you might not know about lightning. While the flashes we see as a result of a lightning strike travel at the speed of light ,, mph an actual lightning strike travels at a comparatively gentle , mph.
This means it would take about 55 minutes to travel to the moon, or around 1. When lightning strikes sand or sandy soil, it fuses together the grains to create a small glass-like tube known as a fulgurite. They are not only prized by collectors, they are also of great scientific value in demonstrating past occurrence of lightning storms. Lake Maracaibo in Venezuela is the place on Earth that receives the most lightning strikes.
Massive thunderstorms occur on nights per year with an average of 28 lightning strikes per minute lasting up to 10 hours at a time. Recent research from the Met Office revealed that helicopters can cause an isolated lightning strike. While flying, the helicopter acquires a negative charge, so if it flies close to an area that is positively charged e. Investigating and predicting helicopter-triggered lightning strikes. Lightning is one of nature's most recurrent and common spectacles.
Around the world, there are over 3,, flashes every day.
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