Stunning details and security suggestions for lightning and thunderstorms

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Thunderstorms are a staple of summer in the Lower 48, and they all produce lightning, a wild phenomenon that can also be dangerous. DC on Thursday two people were killed after being hospitalized for injuries sustained in an apparent lightning strike near the White House.

These heaves of raw electricity ricochet through thin air, shoot out of stormy skies and blast anything with a deafening roar. Lightning can be mesmerizing, dangerous, beautiful and terrifying, but how much do you know about what happens when it strikes?

Two people were killed after a lightning strike near the White House on Thursday night

Lightning is an electrical discharge and nature’s balancing mechanism that distributes charge throughout the atmosphere.

Thunderstorms become electrified when electrons, which are negatively charged particles, are sheared off one water particle—such as a raindrop, snowflake, or hailstone—and land on another, leaving the first positively charged and the second slightly negatively charged. Generally speaking, ice crystals acquire a positive charge, while raindrops acquire a negative charge.

As a result, the top of the cloud, where the temperature is well below freezing, is positively charged. Below is a wider “center negative” inside the storm. A shallow, broad positive charge is at the base of the storm like the bottom of a hamburger bun.

Most of the lightning we see is within a cloud (cloud) or in the form of cloud-to-ground bolts, most commonly occurring from the middle negative charge. The greater the electric field in the cloud, the “sparkier” the storm will be.

Making an electric spark jump through thin air is tricky. The ambient electric field must be high enough to exceed the “dielectric breakdown strength” of air.

Think of a dam. It prevents water from flowing past it unless the volume of water behind it reaches a limit sufficient to break the dam. The accumulated water can then seep through undisturbed.

In the case of air, this magic number is 3 megavolts (or 3 million volts) per meter when the air is dry (it will change slightly during a storm). The charge that builds up on the surface will begin to flow into the thin air in a tiny stream of electrons called a “corona” discharge. This heats the surrounding air, reducing drag and allowing the sparks to begin spreading in uneven steps.

It’s not clear what processes take place in the cloud, but eventually what’s called a “stepped electrical leader” moves toward the ground, dancing in a branching, fractal pattern.

What I’ve learned from 20 years of DC lightning photography

“Upstreams” or narrow strands of electricity reach the sky from the surface, similar to a group of students raising their hands. Eventually, the downward leader joins one of the upward streams to create a continuous electrical channel between the cloud and the ground. Pulses of current surge through the channel, each one producing a burst of light. That’s why lightning looks like it’s flashing.

Surprising facts about lightning

  • Lightning is not that thick. In fact, it is only an inch or two in diameter. It just looks wider because of the brightness.
  • Lightning is five times hotter than the surface of the sun. In this narrow lightning channel, electricity heats the air to nearly 55,000 degrees. This causes the air to expand rapidly, which creates the atmospheric shock wave we hear as thunder.
  • Lightning may strike. Scientists at New Mexico’s Los Alamos National Laboratory use rockets to trigger lightning and then use high-speed cameras and instruments to collect data. It is also well known that airplanes, helicopters, tall man-made structures and even wind turbines can cause their own impacts.
  • “Lightning Up” is a thing. It’s exactly what it sounds like, lightning leaping from the ground into the cloud, spreading outward along the broad lower positive charge of the cloud. In fact, autonomous leaders originate from man-made transmission/broadcasting towers and are an area of ​​emerging research.
  • Some lightning strikes are more likely to start wildfires. Although lightning is very hot, it is also short. This limits her ability to start a fire. But instead of the current flowing between the sky and the ground in short, staccato bursts, some lightning takes the form of a “direct current” discharge. This means that the current flows in pulses of longer duration. Since the current heats the ground longer, the chance of a fire increases significantly.
  • Men are affected about four times more often than women. In the United States, men account for 84 percent of lightning deaths, and women account for the remaining 16 percent.
  • The number of lightning deaths is decreasing. Due to better forecasting, education and awareness, lightning deaths have decreased significantly in recent decades. Since 1989 until 2018 In the United States, an average of 43 people die each year from lightning strikes, but between 2012 and 2022 the average decreased to 23. In 2021 a record low of 11 deaths occurred.

Tips and facts you need to know to protect yourself from lightning

  • Never hide under a tree. If lightning strikes a tree, the charge may flow through the trunk and laterally strike those below or spread through the ground. Many lightning tragedies have resulted from individuals seeking shelter under trees. The previous DC lightning death occurred in 1991. May 17 occurred when the group hiding under a tree during a lacrosse game.
  • Recreational activities, especially fishing and boating, are the largest sources of lightning deaths. “[F]sailors and boaters are likely to be outdoors and more vulnerable to a direct lightning strike,” report from the National Lightning Safety Council as of 2020.
  • Lightning can strike even during a blizzard. Thunderstorms are real and can be dangerous. in 1990 January 25 lightning struck a light pole during a thunderstorm in Crystal Lake, Illinois. The projectile traveled across the frozen ground, injuring 11 bystanders digging snow or pushing stranded motorists.
  • Lightning can travel 10 or more miles from the main thunderstorm and even hit in the fresh air away from the rain. These “bolts out of the blue” are often more powerful and powerful because they come from the top of a positively charged thunderstorm. These are among the most dangerous because they can strike in otherwise calm conditions. That’s why experts recommend taking cover at the first sign of a thunderstorm, which is a sign that you’re close enough to be struck by lightning.
  • Ninety percent of lightning strike victims survive. In the United States, lightning kills an average of 30 people each year. The lightning The strike outside the White House on Thursday brought the death toll to 11 this year.

Read more about lightning…

“Giant jet” lightning is a mystery. These researchers address it.

Jonathan’s Story: After a Tragic ‘Gateway Out of the Blue’ Two Simple Rules That Could Save Your Life

Bolts from the clear: This is how lightning can strike when the storm is tens of miles away

Where lightning struck the most in the US in 2021

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