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A person can call himself the king of nature, but often nothing can oppose it. When nature begins to get angry, then all that remains for us is to hide, run, and restore what was destroyed. One of the most famous natural disasters is the hurricane. You can call it a tropical cyclone or typhoon, but this does not change the essence.

The Japanese called the "divine wind" the word "kamikaze". The tornado is different in that the winds are stronger here than in a hurricane. But this phenomenon does not last long. Hurricanes can reach entire states in size, they are most active for several days. Waves appear, reaching 5 and even 15 meters in height.

Those caught in the path of such hurricanes should know how they are. The most interesting thing about hurricanes remains unknown.

There is a lot of snow and ice in hurricanes. These formations appear at high temperatures. But the clouds go up kilometers into the troposphere. It is there that the weather on the planet is mainly formed. The largest hurricanes have hot pillars that can even reach the stratosphere. At this altitude, the low temperature is about 50 degrees below zero, and the humidity there turns into ice and snow. Those caught in the hurricane report that the sky fogs up about a day before the storm starts. Cirrus clouds are to blame for the fogging, they are part of the flow of moisture and heat that underlies the hurricane. The clouds themselves are composed of ice crystals and are visible even in images from space. Most of the snow particles fall from the upper tier and immediately melt. But something remains above. Recent research has shown that ice ejected into the stratosphere by hurricanes can even contribute to global warming.

Hurricanes "breathe" and "blink". The inhalation of the hurricane comes from the surface of the ocean. The air does not flow directly due to the Coriolis effect. Because of this, in the northern hemisphere, the wind deviates counterclockwise, and in the southern hemisphere, clockwise. The effect prevents the inflow from reaching the center of low pressure. A strong wind surrounds the center and rises upward, thus the “eye” wall appears. This inflow rises upwards for tens of kilometers, and then it also swirls outward from the center in the form of a cirrus outflow. Exhalation flows in the opposite direction to that coming from the surface. And part of the rising air is not included in the hurricane. It slows down and descends to the surface, losing its moisture and clouds in the process. This clear-weather central eye area is the calmest during a storm. But the situation can change quickly. Large hurricanes have eye wall changing cycles, during which it shrinks in size. The eye "blinks" and fills with clouds, and then opens again. This is due to the formation of a new eye wall.

Registration of hurricanes by seismographs. Water is a rather heavy substance. An ordinary wave contains a large volume of liquid. The fluctuations in the water surface that occur during a hurricane in size, and, consequently, in mass, are much larger than usual. During a hurricane, waves receive a powerful impulse, which determines their speed. They hit the ground with great force, from which even the earth trembles. Giant waves collide with each other and in the ocean, generating a low-frequency sound. Scientists discovered such seismic waves in the early 20th century, they thought it was just background noise. And only half a century later it became clear that infrasonic seismic signals are generated by hurricanes. In 1938, signals from Category 5 hurricanes that hit the East Coast were recorded by seismographs in Alaska. Modern devices are much more sensitive. Superstorm Sandy's activity was recorded on all seismographic tables throughout the United States. With the help of seismographs, scientists have even learned to track changes in air pressure in a hurricane.

The appearance of a hurricane. No one really knows what exactly triggers the appearance of a hurricane. It is believed to appear when warm humid air rises above the ocean. This creates a zone of reduced pressure. New air is attracted there, it also heats up, receives moisture and lifts up. This starts a cycle with air constantly circling the surface. Rising up, it cools and turns into thunderclouds. They combine and form first a tropical depression, then a storm, and then a hurricane. Experts are concerned that this does not always happen even if all the necessary conditions exist. A hurricane should form, but it doesn't. This means that something else is the reason for its appearance. Scientists were only able to identify some auxiliary factors - vorticity and gradient of wind speed, but others remain a mystery. Hurricanes are born the way they please, confusing researchers every time.

Impact on the Atlantic hurricanes of the Sahara Desert. It turns out that if the Sahara Desert did not exist, then there would be fewer hurricanes. The fact is that the huge desert is located in a critical place, close to the equator. To the south and north lie cooler, humid regions. When hot and dry air mixes with slightly colder and humid air, an east wind is born. Called the East African jet stream, it is responsible for the appearance of tropical air waves. Those near the sea subside, but under the right conditions and with a number of factors, they can turn into a hurricane. About 90 percent of all large formations of this kind appear this way. This also applies to hurricanes that occur in the eastern Pacific Ocean. It seems odd that the mighty Isel that hit Hawaii in 2014 was originally an African tropical wave. But the Sahara can also prevent a hurricane from appearing. Desert air currents are a mass of dry air with sand particles. It travels from the desert westward across the Atlantic, alongside tropical waves. Such currents can destroy the developing tropical system by decreasing its humidity, creating a temperature inversion, increasing the wind speed gradient. So the tropical system will be destroyed by the same desert that gave birth to it.

Hurricanes release a lot of energy. It's no secret that these formations are characterized by regular rains, strong winds and high humidity in stuffy conditions. But many do not even realize that hurricanes are born at high temperatures, which are the result of cloud formation and rain. You can understand this by going in and out of the pool or bath. We immediately begin to feel colder, even if the water was warm. It's just that droplets from our skin begin to evaporate into the air. Hurricanes initiate this process in the opposite direction. They use condensation to draw water out of the air and release heat. Hurricanes have a large supply of moisture and air, which allows them to release an impressive amount of thermal energy. Due to the creation of clouds and the formation of rain, a hurricane can release 200 times more energy than is generated during this time on the entire planet. So nature has its own powerful heat engines.

Clear hurricane boundaries. Although the destructive energy of hurricanes is frightening, massive storms still have to obey some laws of physics. The Coriolis effect causes formations to rotate in a specific way. Because of this, hurricanes cannot cross the equator. Another principle, the Fujiwara effect, states that two cyclones may not merge, even if they rotate next to each other. Both cyclones should not be tropical. If Fujiwara interacts with a normal low-pressure area, then a powerful hurricane, like Sandy, will result. It was initially heading for the sea, then turned around and hit the East Coast. Hurricanes can also be weakened if they churn up the warm upper layers of the ocean and push cold water up. Because storms require high temperatures, the cold water prevents them from intensifying and can extinguish a hurricane altogether.

Loops of Australian cyclones. Traditionally, hurricanes have to pass through any global wind belt in which they happen to be. This explains why hurricanes in the Northern Hemisphere head west first and then veer north and east. First, they are "pushed" to the equator by the eastern tropical trade winds. If hurricanes manage to survive long enough above the water, they already face the prevailing westerly winds. That is why hurricanes, which seem to threaten the eastern shores of America, go to sea. The exception is the situation with Hurricane Sandy in 2012, when the Fujiwara effect was stronger than the directional winds. The general rules should work in the Southern Hemisphere as well. They operate there, but not in Australia. Research has shown that tropical cyclones move more erratically there than elsewhere. These objects not only make cool conversations, but they even perform loops. For meteorologists, predicting the behavior of local hurricanes is a real headache. The reasons for this phenomenon are still unclear. Hurricanes are somehow influenced by local weather.

Tornadoes caused by hurricanes. Tornadoes are rotating storm systems like a hurricane. However, it is simply larger and lives longer. This is why hurricanes are more destructive. In addition, they are able to form tornadoes, sometimes even several days after they appear at the coast. A tornado can form after a hurricane reaches the ground and begins to fade. This is due to the distance from the water source of heat. In the tropics, this decay generates winds of different speeds at different altitudes. The speed gradient is what causes the tornado. Usually they do not exceed the F2 level on the Fujita scale, however, they can very well cause destruction and death. While most tornadoes are born in the outer lane, some appear near the center somehow. Experts believe that the damage caused by the hurricane's eye wall could actually come from a tornado. Nearly all hurricanes that ravage America still form tornadoes before moving inland. This suggests that hurricanes from the northern Gulf Coast are generating more tornadoes. But hurricanes from the East Coast only partially touch the ground. Basically, they remain in the open sea, away from the coast.

Hurricanes can intensify and change. In the Atlantic, tropical cyclones are called hurricanes, and in some parts of the Pacific they are called typhoons. In fact, these are all the same storms. Half of them in the North Atlantic and a third in the Pacific Ocean turn into extratropical cyclones. This does not make them special in any way, just their actions are not based on heat. Huge rotating cyclones exist due to the difference in air temperature. And such cyclones are quite dangerous. In 1991, a hurricane began, which then escalated into an extratropical cyclone "Ideal Storm". He sank the ship Andrea Gale and devastated New England in 1991. But after an extratropical transition, the cyclone usually disappears quickly. But even here lies the danger. A hurricane that comes with its own heat reserve and temperature drop may even intensify. This is exactly what happened with Perfect Storm in 1991, as well as Superstorm Sandy in 2012 on the East Coast.

Watch the video: 3. Saturday update on Hurricane Isaias

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