A hailstone can weigh more than two pounds (0.9 kilograms).
Photograph by Jim Reed/Photo Researchers, Inc
Nature
can be unbelievably powerful. A major earthquake can topple huge
buildings and bring down entire mountainsides. At Niagara Falls, more
than 500,000 gallons (1,892,705 liters) of water crash down 18 stories
into the Niagara River every second—enough to fill nearly 50
Olympic-size swimming pools in a minute! And everyone knows about
hurricanes, blizzards, avalanches, forest fires, floods, tidal waves,
and even thunderstorms. But if you thought Mother Nature didn't have
many surprises up her sleeve, think again. Nature has a load of other
powers that, while less well-known, can only be described as, well,
freaky.
The Mother of All Tornadoes
The fastest wind speed ever recorded—318 miles an hour (511 kilometers an hour)—occurred during a tornado near Oklahoma City in 1999. Scientists classify tornadoes by the damage they can do. A tornado with wind speeds of 70 miles an hour can sweep away entire houses and hurl cars through the air like missiles. But a tornado with wind speeds of more than 300 miles an hour has the power to derail train cars, tear grass from the ground, and even rip pavement from the street.
Dodge Balls
About 1,000 years ago hundreds of people were mysteriously killed in the Himalaya. A recent investigation concluded that they were caught in a hailstorm that dropped chunks of ice the size of baseballs on the victims' heads at more than 100 miles an hour (160 kilometers an hour). Hail is formed in storms when raindrops are carried into extremely cold areas of the atmosphere by powerful vertical winds. The longer the tiny specks of ice bounce around in the wind, the bigger they become. When the clumps of ice grow too big for the wind to hold up, they fall to the ground as hail.
The Mother of All Tornadoes
The fastest wind speed ever recorded—318 miles an hour (511 kilometers an hour)—occurred during a tornado near Oklahoma City in 1999. Scientists classify tornadoes by the damage they can do. A tornado with wind speeds of 70 miles an hour can sweep away entire houses and hurl cars through the air like missiles. But a tornado with wind speeds of more than 300 miles an hour has the power to derail train cars, tear grass from the ground, and even rip pavement from the street.
Dodge Balls
About 1,000 years ago hundreds of people were mysteriously killed in the Himalaya. A recent investigation concluded that they were caught in a hailstorm that dropped chunks of ice the size of baseballs on the victims' heads at more than 100 miles an hour (160 kilometers an hour). Hail is formed in storms when raindrops are carried into extremely cold areas of the atmosphere by powerful vertical winds. The longer the tiny specks of ice bounce around in the wind, the bigger they become. When the clumps of ice grow too big for the wind to hold up, they fall to the ground as hail.
Light Show
Vast glowing rings, called auroras, often appear far above the North and South Poles. These rings can be more than 12,000 miles (19,312 kilometers) around. People who live near polar regions see the auroras as giant curtains of shimmering light in a variety of colors. This beautiful effect occurs when charged particles, shot past the Earth by the sun at more than a million miles an hour (1,609,344,000 kilometers an hour), are caught in the Earth's magnetic field and funneled to the Poles. When these particles hit gases in our atmosphere, the gases give off light. People in the far northern and southern regions can enjoy the greatest natural light shows on Earth.
It's Raining Frogs!
Small frogs rained on a town in Serbia, sending residents running for cover. "There were thousands of them," a villager told a local newspaper. "I thought maybe a plane carrying frogs had exploded in midair," said another resident. Had the town gone crazy? Probably not. Scientists believe that waterspouts and tornadoes can suck up the surfaces and lakes, marshes, and other bodies of water. When they do, they can take frogs and fish along for the ride. The tornadoes can then drop them miles away.
Flaming Twisters
As if tornadoes aren't dangerous enough, one kind is made of fire. Wildfires are so powerful they can create their own weather. As these fires burn, they consume huge quantities of oxygen. The intense heat causes the air to rise. When fresh air swoops in and replaces it, strong winds are produced. Sometimes this self-created weather, or microweather, causes swirling tornadoes of fire. These flame-throwing tornadoes, called fire whirls, can be 50 feet (15 meters) wide and grow as tall as a 40-story building.
Gas Attack
When a volcano erupts, a glowing sea of molten lava often flows down its sides, destroying everything in its path. A lava flow is unbelievably dangerous. But a volcano can produce something even deadlier: a pyroclastic flow, which is a cloud of gas and rock that can reach temperatures above 1,000 degrees Fahrenheit (537 degrees Celsius). The flow crashes down the side of a volcano like an avalanche. While most people can easily move out of the way of most lava flows, they can't escape a pyroclastic flow so easily. These flows typically reach speeds of more than 50 miles an hour (80 kilometers an hour).
Snowball Factory
You head outside after a snowstorm and see dozens of log- or drum-shaped snowballs. These rare creations are called snow rollers, and Mother Nature makes them all by herself. Snow rollers form when wet snow falls on ground that is icy, so snow won't stick to it. Pushed by strong winds, the snow rolls into logs. Maybe this is nature's way of saying it's time for a snowball fight.
Deep Sea Jacuzzis
Vents on the ocean floor, more than a mile (1.6 kilometers) below the surface, gush what looks like clouds of black smoke. They're surrounded by a variety of freaky life forms never seen before the first vents were discovered about 30 years ago. These underwater hot springs, called hydrothermal vents, occur when water seeps through cracks in the ocean floor after being heated by magma inside the Earth. The scalding water can shoot back into the cold ocean at temperatures hotter than 700 degrees Fahrenheit (371 degrees Celsius), carrying a black or white stew of dissolved rock and chemicals. Amazingly, these vents support large communities of bizarre sea creatures. These life-forms rely on millions of bacteria inside them to turn poisonous chemicals rising from the seafloor into food.
Mystery WavesWhen a volcano erupts, a glowing sea of molten lava often flows down its sides, destroying everything in its path. A lava flow is unbelievably dangerous. But a volcano can produce something even deadlier: a pyroclastic flow, which is a cloud of gas and rock that can reach temperatures above 1,000 degrees Fahrenheit (537 degrees Celsius). The flow crashes down the side of a volcano like an avalanche. While most people can easily move out of the way of most lava flows, they can't escape a pyroclastic flow so easily. These flows typically reach speeds of more than 50 miles an hour (80 kilometers an hour).
Snowball Factory
You head outside after a snowstorm and see dozens of log- or drum-shaped snowballs. These rare creations are called snow rollers, and Mother Nature makes them all by herself. Snow rollers form when wet snow falls on ground that is icy, so snow won't stick to it. Pushed by strong winds, the snow rolls into logs. Maybe this is nature's way of saying it's time for a snowball fight.
Deep Sea Jacuzzis
Vents on the ocean floor, more than a mile (1.6 kilometers) below the surface, gush what looks like clouds of black smoke. They're surrounded by a variety of freaky life forms never seen before the first vents were discovered about 30 years ago. These underwater hot springs, called hydrothermal vents, occur when water seeps through cracks in the ocean floor after being heated by magma inside the Earth. The scalding water can shoot back into the cold ocean at temperatures hotter than 700 degrees Fahrenheit (371 degrees Celsius), carrying a black or white stew of dissolved rock and chemicals. Amazingly, these vents support large communities of bizarre sea creatures. These life-forms rely on millions of bacteria inside them to turn poisonous chemicals rising from the seafloor into food.
Imagine you're on an ocean liner when a wall of water ten stories tall races toward you like an unstoppable freight train. It's not a tsunami, caused by an undersea earthquake. Tsunamis are tiny in the open ocean and become enormous—and deadly—as they approach the shore. No, what you're witnessing at sea is a rogue wave, also called a freak wave. Scientists aren't sure what causes these waves, but they do know they can appear without any warning in the open sea, even in the clearest of weather. As recently as 15 years ago these waves were thought to be a myth. But scientists now know they are very real—and very dangerous to even the largest ships.
Great Balls of Fire
During a thunderstorm, a glowing ball the size of your head suddenly appears. It hovers a few feet above the ground, drops down, dances across the yard, and then darts up into the air before it fades away. This freaky phenomenon is ball lightning. Sometimes it disappears with a small explosion. Some scientists think that when normal lightning strikes the ground, it vaporizes a mineral called silicon found in soil. They think this silicon forms a kind of bubble that burns in the oxygen around it.
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