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Why Tornado Exist – the science behind

They call me the tornado chaser. When the wind is up and conditions are right, I get in my car and follow violent storms. “Crazy,” you say? Perhaps, but really I chase these sky beasts to learn about them. I want to share with you what I know. Tornadoes are rapidly rotating columns of air that form inside storms that connect with the ground via a funnel of cloud.

When that happens, they tear across the Earth, posing a huge threat to life and property. Because of this, there’s a great deal of research into these phenomena, but the truth is, there’s still a lot we don’t know about how tornadoes form. The conditions that may give rise to one tornado won’t necessarily cause another. But we have learned a lot since people first started recording tornadoes, like how to recognize the signs when one is brewing in the sky.

Are you coming along for the ride? Tornadoes begin with a thunderstorm but not just any thunderstorm. These are especially powerful, towering thunderstorms called supercells. Reaching up to over 50,000 feet, they bring high force winds, giant hailstones, sometimes flooding and great flashes of lightning, too.

These are the kinds of storms that breed tornadoes, but only if there are also very specific conditions in place, clues that we can measure and look out for when we’re trying to forecast a storm. Rising air is the first ingredient needed for a tornado to develop.

Any storm is formed when condensation occurs, the byproducts of the clouds. Condensation releases heat, and heat becomes the energy that drives huge upward drafts of air. The more condensation and the bigger the storm clouds grow, the more powerful those updrafts become. In supercells, this rising airmass is particularly strong.

As the air climbs, it can change direction and start to move more quickly. Finally, at the storm’s base, if there is a lot of moisture, a huge cloud base develops, giving the tornado something to feed off later, if it gets that far. When all these things are in place, a vortex can develop enclosed by the storm, and forming a wide, tall tube of spinning air that then gets pulled upwards. We call this a mesocyclone.

Outside, cool, dry, sinking air starts to wrap around the back of this mesocyclone, forming what’s known as a rear flank downdraft. This unusual scenario creates a stark temperature difference between the air inside the mesocyclone, and the air outside, building up a level of instability that allows a tornado to thrive.

Then, the mesocyclone’s lower part becomes tighter, increasing the speed of the wind. If, and that’s a big if, this funnel of air moves down into that large, moist cloud base at the bottom of the parent storm, it sucks it in and turns it into a rotating wall of cloud, forming a link between the storm that created it and the Earth.

The second that tube of spinning cloud touches the ground, it becomes a tornado. Most are small and short-lived, producing winds of 65-110 miles per hour, but others can last for over an hour, producing 200 mile per hour winds. They are beautiful but terrifying, especially if you or your town is in its path.

In that case, no one, not even tornado chasers like me, enjoy watching thing unfold. Just like everything, however, tornadoes do come to an end. When the temperature difference disappears and conditions grow more stable, or the moisture in the air dries up, the once fierce parent storm loses momentum and draws its tornado back inside.

Even so, meteorologists and storm chasers like me will remain on the lookout, watching, always watching to see if the storm releases its long rope again.

Find it Here How tsunamis work?

In 479 BC, when Persian soldiers besieged the Greek city of Potidaea, the tide retreated much farther than usual, leaving a convenient invasion route. But this wasn’t a stroke of luck. Before they had crossed halfway, the water returned in a wave higher than anyone had ever seen, drowning the attackers.

The Potiidaeans believed they had been saved by the wrath of Poseidon. But what really saved them was likely the same phenomenon that has destroyed countless others: a tsunami. Although tsunamis are commonly known as tidal waves, they’re actually unrelated to the tidal activity caused by the gravitational forces of the Sun and Moon. In many ways, tsunamis are just larger versions of regular waves. They have a trough and a crest, and consist not of moving water, but the movement of energy through water.

The difference is in where this energy comes from. For normal ocean waves, it comes from wind. Because this only affects the surface, the waves are limited in size and speed. But tsunamis are caused by energy originating underwater, from a volcanic eruption, a submarine landslide, or most commonly, an earthquake on the ocean floor caused when the tectonic plates of the Earth’s surface slip, releasing a massive amount of energy into the water.

This energy travels up to the surface, displacing water and raising it above the normal sea level, but gravity pulls it back down, which makes the energy ripple outwards horizontally. Thus, the tsunami is born, moving at over 500 miles per hour. When it’s far from shore, a tsunami can be barely detectable since it moves through the entire depth of the water. But when it reaches shallow water, something called wave shoaling occurs. Because there is less water to move through, this still massive amount of energy is compressed.

The wave’s speed slows down, while its height rises to as much as 100 feet. The word tsunami, Japanese for “harbor wave,” comes from the fact that it only seems to appear near the coast. If the trough of a tsunami reaches shore first, the water will withdraw farther than normal before the wave hits, which can be misleadingly dangerous. A tsunami will not only drown people near the coast, but level buildings and trees for a mile inland or more, especially in low-lying areas.

As if that weren’t enough, the water then retreats, dragging with it the newly created debris, and anything, or anyone, unfortunate enough to be caught in its path. The 2004 Indian Ocean tsunami was one of the deadliest natural disasters in history, killing over 200,000 people throughout South Asia. So how can we protect ourselves against this destructive force of nature?

People in some areas have attempted to stop tsunamis with sea walls, flood gates, and channels to divert the water. But these are not always effective. In 2011, a tsunami surpassed the flood wall protecting Japan’s Fukushima Power Plant, causing a nuclear disaster in addition to claiming over 18,000 lives.

Many scientists and policy makers are instead focusing on early detection, monitoring underwater pressure and seismic activity, and establishing global communication networks for quickly distributing alerts. When nature is too powerful to stop, the safest course is to get out of its way.