How Come?

Why are hurricanes named after people, and in a certain order? ask Melissa Vallance and Kelli Day, students in Holtsville, NY.

While a tornado would have skipped to the next county and disappeared before you could call it “Ralph,” hurricanes take their sweet time building up their winds, moving towards coastlines and back out to sea at a stately pace. So it’s important to identify these big storms for pilots, ships, and people living in a hurricane’s path.

In the U.S. before the 1950s, hurricanes were identified by latitude and longitude, a system that became confusing when there was more than one tropical cyclone brewing at a time. In the early 50s, the U.S. decided to name storms using the Army/Navy phonetic alphabet, devised for World War II military communications: Able, Baker, Charlie, etc. So in 1952, the news reported on Hurricane Dog, Hurricane Easy, and Hurricane Fox. (If the tropical storm season had been busier, coast-dwellers might have been threatened by Hurricanes How, Item, Love, Sugar, Uncle, X-ray, and Zebra.)

Human beings have a long history of personifying nature (as in Thor, the Norse god of thunder), so using human names for big storms makes sense. Hurricanes that hit the West Indies in the 19th and early 20th centuries were named after saints. And in the 1940s, weather forecasters often gave hurricanes women’s names, like World War 2 fliers naming their fighter planes.

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Why do leaves change color in the fall? asks Patricia Brown, of New York City.

Autumn’s cool days are trimmed with deep blue skies and golden light, and brilliant leaves of yellow, orange and red. Leaves changing color in the fall are a tree’s way of preparing for long winter, rather like we put up storm windows and pull warm clothes and blankets out of storage.

In summer, the leaves on trees like pin oaks and sugar maples are green because they are chock-full of the green pigment chlorophyll.

Trees need sunlight to produce chlorophyll. In turn, chlorophyll uses sunlight’s energy to split water (H2O) into hydrogen and oxygen. Meanwhile, leaves also absorb carbon dioxide gas from the air. The end products of leaf chemistry: carbohydrates (homemade plant food for the tree), and oxygen, released into the air (the gas we need to breathe). The whole process is called photosynthesis.

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Where do bugs like flies go when the weather gets cold, so they can appear like magic when it gets warm again? asks Jonathan Conway, of Syosset, NY.

Unfortunately, many insects don’t survive the freezing cold of winter. Others, however, have come up with clever schemes to hang on until spring.

For example, cluster flies sometimes hide out in the nooks and crannies of a warm house or barn over the winter, venturing out to fly around only on milder winter afternoons.

Mosquitoes, like bears, hibernate through the winter cold. Adult mosquitoes look for dark, damp, hiding places–like your basement–to spend their winter vacation. In spring, the females slowly become active, flying around looking for food (fresh blood). Once they’ve had their blood meal, they’re ready to lay eggs, and hatch a new crop to plague us during the summer.

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What is ball lightning? asks Kelly Corcoran, a student in Babylon, NY.

Stories of ball lightning date back to at least the Middle Ages, and scientists estimate that at least five percent of our planet’s population have had the privilege (or, sometimes, the misfortune) to have seen the glowing, floating spheres.

According to eyewitnesses, ball lightning appears as a radiant sphere, ranging in size from a baseball to a basketball. It may be white, yellow, red, orange, or blue, and is usually no brighter than a 100-watt light bulb.

The glowing ball often floats 2 to 6 feet or more above the ground as it travels, sometimes spinning as it moves back and forth, here and there. After seconds—or minutes—the ball goes out with a hiss, pop, or a loud bang. Like a July 4th sparkler, ball lightning may emit an acrid smell like burning sulfur or ozone, and leave smoke behind. Most ball lightning is seen just before or during a thunderstorm, within seconds of a lightning strike.

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