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Whether referred to as a hurricane, typhoon, or tropical cyclone, this fierce and remarkable force of nature is known as kamikaze (the Japanese term for 'divine wind'). While tornadoes have more intense winds than hurricanes, they are much smaller and short-lived. Hurricanes, on the other hand, can cover areas up to half the size of the contiguous United States, maintaining their peak strength for several days. Along with torrential rains, hurricanes also bring massive surges of seawater, reaching up to 6 meters (20 feet) high, with waves soaring to 15 meters (50 feet).
Anyone in the storm's path should familiarize themselves with hurricane safety guidelines. Once you've taken the necessary precautions to safeguard your property and well-being, you can pass the time by exploring some of the intriguing facts about hurricanes.
For example, did you know that . ...
10. Hurricanes Are Packed with Snow and Ice
Hurricanes are powered by heat, and their clouds can extend several kilometers into the sky, reaching all the way up to the troposphere (where most of Earth’s weather takes place). Large hurricanes feature “hot towers” that can stretch into the stratosphere. The temperatures up there are extremely cold, about –51 degrees Celsius (–60 °F), causing the moisture in the upper layers of the hurricane to freeze into ice and snow. If you've ever experienced a hurricane, you’ve noticed the haziness that settles in a day before the storm. This haze is caused by cirrus clouds, which are part of the hurricane’s outflow and are composed of ice crystals. These clouds are also strikingly visible in satellite imagery.
Eventually, most of this frozen material falls from the high clouds and melts once again. However, some of it ascends further. Recent studies suggest that the ice ejected by hurricanes into the stratosphere could play a role in global warming. The term “cirrus outflow” simply refers to the hurricane ‘exhaling,’ because . . ...
9. Hurricanes Exhale, and Their Eyes ‘Blink’
A hurricane inhales at the ocean’s surface. Without the Coriolis effect, the air would flow directly in, but the Coriolis effect deflects it—counterclockwise in the Northern Hemisphere and clockwise in the Southern Hemisphere. This deflection also prevents the air from reaching the center of low pressure. Instead, the wind is forced to circulate around the center and rise, creating the eyewall.
The air rushes up to tens of thousands of meters before spiraling outward as cirrus outflow. This icy outflow moves in the opposite direction of the surface winds. Meanwhile, some of the rising air doesn’t escape the hurricane. It slows down, sinks back toward the surface, and dries out, losing its clouds. This area in the center becomes the calmest part of the storm. However, things can change rapidly. Major hurricanes experience eyewall replacement cycles, during which the eye shrinks. It ‘blinks’ (fills with clouds) and then opens again as a new eyewall forms.
8. Hurricanes Show Up on Seismographs
Water is dense. A typical ocean wave carries a significant amount of water, and the colossal waves produced by a hurricane dwarf all others in both size and weight. In a hurricane, these waves travel quickly, packed with immense momentum. As a result, they crash onto land with tremendous force, even making the Earth tremble. These massive waves can collide far from the shore, similar to Jaegers and Kaiju in Pacific Rim, generating low-frequency sound waves.
When scientists first detected these seismic waves in the 1900s, they dismissed them as mere background noise. It wasn’t until the mid-20th century that they discovered hurricanes were responsible for creating these seismic and infrasound signals. For example, in 1938, signals from a category five hurricane that struck the East Coast appeared on seismographs in Sitka, Alaska. Today’s highly sensitive seismometers can pick up these signals, so it’s no surprise that Superstorm Sandy, for instance, triggered seismic arrays across the United States. Researchers have also used seismometers to monitor air pressure shifts during hurricanes.
7. The Exact Cause of a Hurricane’s Formation Remains Unknown
Generally, scientists believe a hurricane begins when warm, moist air over the ocean rises, creating a pocket of low air pressure. As more air flows into this area, it becomes warm and humid enough to start rising as well. This initiates a cycle where air continuously swirls inward at the surface, while the rising air cools, forming clouds and thunderstorms. Eventually, these thunderstorms merge into a tropical depression, then a tropical storm, and finally—a hurricane.
What confounds meteorologists is that this process doesn’t occur every time the conditions are right. While it should, it often doesn’t. Some unknown factor triggers hurricanes, and the best minds in science are working to pinpoint exactly what triggers this process. Although certain factors, like wind shear and vorticity, have been identified, there’s still disagreement about others.
In the meantime, hurricanes do whatever they want, leaving many confused meteorologists in their wake.
6. The Sahara Desert Impacts Hurricanes in the Atlantic
Without the Sahara Desert, there would be fewer hurricanes. Why is that? This vast desert is strategically located near the equator, with cooler, wetter regions to its south and west. When hot, dry air meets cooler, damp air, it creates an easterly wind known as the “African easterly jet” that forms tropical waves. These waves travel out to sea and, under the right conditions, can develop into hurricanes. In fact, almost 90 percent of major hurricanes form in this manner.
This phenomenon also affects hurricanes in the East Pacific. Surprisingly, in 2014, Hurricane Iselle—the strongest storm to ever hit Hawaii’s Big Island—started off as an African tropical wave. However, the Sahara can also prevent hurricanes from forming. The “Saharan Air Layer” is a large mass of dry, sandy air that drifts westward over the Atlantic, often interfering with tropical waves. This air can strip away necessary moisture, create a temperature inversion, or increase wind shear, which can dismantle developing tropical systems.
5. Hurricanes Release an Incredible Amount of Energy
It’s well-known that hurricanes bring powerful winds, heavy rain, and extreme humidity. But what many don’t realize is that hurricanes derive their power from heat produced by cloud formation and rainfall. This may seem mysterious, but it’s a simple process. Imagine stepping in and out of a warm pool or bathtub—you feel cooler because the water droplets on your skin evaporate. Hurricanes essentially work in reverse, pulling moisture out of the air through condensation and releasing heat.
With so much air and moisture at their disposal, hurricanes unleash vast amounts of energy. On average, through cloud formation and rainfall, a hurricane releases 200 times the energy generated by all of Earth’s electrical power plants combined. That’s why they’re often called heat engines.
4. Hurricanes Have Well-Defined Boundaries
Hurricanes are incredibly powerful, but their destructive force is still governed by the laws of physics. The Coriolis effect dictates that they must spin in a specific direction and prevents them from crossing the equator. Another limitation is that when two cyclones come close, they don’t merge, but rather, they orbit around each other. This is called the Fujiwhara effect. Interestingly, even if one of the systems isn’t tropical, a Fujiwhara interaction, such as the one that caused Hurricane Sandy to reverse direction and hit the East Coast, can still occur.
Hurricanes can also self-destruct by churning up warm surface water and drawing up colder water from the depths of the ocean. Since hurricanes rely on warm water for energy, the infusion of cold water can drastically weaken them and sometimes completely dissipate the storm.
3. Hurricanes Can Evolve And Grow Stronger
Tropical cyclones are known as hurricanes in the Atlantic and typhoons in parts of the Pacific, but they are essentially the same type of storm. Around half of the hurricanes in the North Atlantic and nearly a third of those in the Pacific eventually transition into 'extratropical cyclones.' This doesn’t mean they become something special; it simply means they no longer derive their energy from heat. Instead, they are fueled by variations in air temperature. Despite this shift, they remain powerful and dangerous. The infamous 'Perfect Storm' that sank the Andrea Gail and wreaked havoc on New England in 1991 began as a hurricane and evolved into an extratropical cyclone.
Once a tropical cyclone undergoes an extratropical transition, it typically weakens quickly. However, it’s important to pay attention during this transition period, as the storm can actually intensify by tapping both its heat reservoir and the temperature contrasts in the atmosphere. This was the case with the Perfect Storm of 1991 and also with Superstorm Sandy in 2012, which grew stronger as it approached the East Coast.
2. Hurricanes Can Produce Tornadoes
While both hurricanes and tornadoes are rotating storm systems, hurricanes are much larger and last longer, making them more destructive than tornadoes. To make matters worse, hurricanes can also generate tornadoes, sometimes several days after making landfall.
Tornadoes can form when a hurricane makes landfall and begins to weaken after losing its source of warm ocean water. This weakening creates varying wind speeds at different altitudes, leading to wind shear that can trigger a tornado. These tornadoes are typically no stronger than an EF2 on the Enhanced Fujita scale, but they can still cause significant damage or even fatalities. Most tornadoes emerge from the outer bands, though some have been spotted near the storm's center. Experts even speculate that some of the severe damage around a hurricane's eyewall may be due to tornadoes.
Nearly every hurricane that reaches the US forms tornadoes, provided the storm travels far enough inland. This is why hurricanes hitting the Gulf Coast generate the most tornadoes, while those on the East Coast often just skim the coastline, staying mostly offshore.
1. Australian Cyclones Play Loop-The-Loop
Hurricanes typically follow the global wind patterns in their path. In the Northern Hemisphere, hurricanes first move westward, then curve northward and eastward. This is because they are initially driven by tropical easterly trade winds, which blow from the east toward the equator. If the storm remains over water and persists, it will eventually encounter the prevailing westerly winds, causing it to curve back toward the sea. This is why storms that appear to be headed toward the eastern US sometimes veer off into the ocean. (Unless, of course, a phenomenon like the Fujiwhara effect, such as during Hurricane Sandy in 2012, overpowers the steering winds.)
These general principles usually apply in the Southern Hemisphere as well. However, they don’t hold true for Australia. Studies indicate that tropical cyclones in Australia behave more unpredictably than those in other regions. They can even make abrupt turns and complete loops. This presents a significant challenge for meteorologists, who are still trying to understand the cause of this behavior, but suspect it may be linked to interactions with local weather systems.
