Why Are Hurricanes and Typhoons More Common in the Pacific?

Typhoon Nepartak swirling over the Pacific Ocean on July 6, 2016
Typhoon Nepartak swirling over the Pacific Ocean on July 6, 2016

 Taiwan endured the impact of ferocious Typhoon Nepartak this month, a storm that crashed ashore with winds equivalent to those of a category four hurricane. The island nation, which sits off the southeastern coast of China, is a regular target for major tropical cyclones, Nepartak being the second such intense storm to come ashore there within the past year. The eastern Pacific Ocean is also hopping this summer, producing one tropical cyclone every couple of days so far this month. Meanwhile, the Atlantic has been dead quiet. This is a common pattern during the summer, and it raises a natural question: Why are hurricanes and typhoons more common in the Pacific Ocean than the Atlantic Ocean?

Tropical cyclones go by many names around the world, and the terminology can get confusing. Once a tropical cyclone strengthens to the point where it has gale-force winds—39 mph or greater—it becomes a tropical storm. A storm that reaches tropical storm strength usually gets its own name to help us quickly identify it in forecasts and warnings.

Once a tropical storm begins producing sustained winds of around 75 mph, we call the storm a typhoon in the western Pacific near Asia and a hurricane in the oceans on either side of North America. A “typhoon” and a “hurricane” are the same kind of storm, they just go by different names.

The Atlantic Ocean sees its fair share of named storms each year, averaging around 11 named storms in a normal season. The eastern Pacific Ocean averages around 16 named storms every year, and the western Pacific churns out more than two dozen named storms in a normal year. There are several factors that contribute to the Pacific teeming with cyclones while the Atlantic can sometimes struggle to see rogue thunderstorms let alone anything more ominous.

THE PACIFIC IS WARMER

Sea surface temperatures (°C) around the world on July 14, 2016. Image credit: NOAA/ESRL/PSD

 
Warm sea surface water is the fuel that drives tropical cyclones. If you ignore large-scale anomalies like El Niño and La Niña, the waters in the Pacific Ocean are usually warmer than those of the Atlantic Ocean, and the temperatures stay pretty toasty through almost the entire year. If you were to take a swim in the water off the coast of the northern Philippines, it would feel like you dunked yourself into a freshly drawn bath, just as it would if you took a dip in the ocean at a beach in Florida. Though parts of the Atlantic get uncomfortably warm, the expanse of hot water is much larger in the Pacific than it is in the Atlantic. The larger pool of steamy water gives more disturbances the opportunity to spin-up into major storms.

The persistent warmth of the western Pacific allows the typhoon season there to last the entire year, unlike around North America where it starts in May in the eastern Pacific and June in the Atlantic, both stretching through November. In addition to ocean currents, which have a major impact on sea surface temperatures, another significant factor in the Atlantic’s relative coolness is its proximity to land.

THE LAND IS A GOOD DEFENSE

Deep cold fronts don’t stop at the beach when they’re finished sweeping across the United States and Canada. Some cold fronts can keep sailing long after they leave shore, traveling across vast swaths of the ocean and dipping as far south as the islands of the Lesser Antilles. The constant train of cold fronts marching out to sea during the early spring and late fall can put the kibosh on tropical cyclone formation, stabilizing and drying out the air and chilling the warm sea surface waters. The Pacific doesn’t have that common issue—most storms stay far enough north that they don’t much affect the typhoon and hurricane seasons across the basin.

Saharan dust crossing the Atlantic Ocean in June 2010. The image was stitched together from a series of images collected by the Moderate Resolution Imaging Spectroradiometer (MODIS) on NASA’s Terra satellite during successive orbits; gray areas show gaps between satellite overpasses. Image credit: NASA Earth Observatory

 
Dry air is also a major problem in the Atlantic Ocean. The Saharan Air Layer (SAL) recently made the news as dust blowing off Africa’s Sahara Desert traveled across the entire ocean and made for some hazy, colorful sunsets in the southeastern United States. These puffs of dry, dusty air coming off Africa don’t only alter our sunsets, but they can have a big effect on tropical cyclones. Dry air is the arch nemesis of tropical cyclones; by their very nature, these cyclones need as much moist air as they can ingest to survive and thrive during their life cycle. Dry air that spirals into the center of a tropical cyclone can collapse the thunderstorms and cause the storm to fizzle out.

Thunderstorms that develop over Africa also serve as the nucleus for some of the worst storms the Atlantic can produce. Disturbances that drift off the African coast can quickly come to life near the Cape Verde Islands, gaining steam as they spiral west toward North America. If western Africa experiences a drought (or the SAL keeps blowing west), it can have a significant impact on the Atlantic hurricane season.

The ironic thing about tropical cyclones is that they produce some of the worst winds on Earth, yet relatively weak winds in the atmosphere can force them to dissipate. Atmospheric wind shear—strong winds that change speed and direction with height—is a death sentence to budding tropical storms. Winds blow the tops off the thunderstorms and prevent them from developing into much more than a brief pulse. Wind shear is also much greater in the tropical Atlantic than it is in the tropical Pacific, both due to regular jet stream patterns and the constant stream of low-pressure systems blowing off North America. 

Why Are Poinsettias Associated with Christmas?

iStock
iStock

Certain Christmas traditions never seem to go out of style. Along with wreaths, gingerbread cookies, and reruns of A Christmas Story sits the poinsettia, a red-tinged leafy arrangement that’s become synonymous with the holiday. Upwards of 100 million of them are sold in the six weeks before December 25.

Why do people associate the potted plant with seasonal cheer? Chalk it up to some brilliant marketing.

In 1900, a German immigrant named Albert Ecke was planning to move his family to Fiji. Along the way, they became enamored of the beautiful sights found in Los Angeles—specifically, the wild-growing poinsettia, which was named after Joel Roberts Poinsett, the U.S.-Mexican ambassador who first brought it to the States in 1828. Ecke saw the appeal of the plant’s bright red leaves that blossomed in winter (it’s not actually a flower, despite the common assumption) and began marketing it from roadside stands to local growers as "the Christmas plant."

The response was so strong that poinsettias became the Ecke family business, with their crop making up more than 90 percent of all poinsettias sold throughout most of the 20th century: Ecke, his son Paul, and Paul’s son, Paul Jr., offered a unique single-stem arrangement that stood up to shipping, which their competitors couldn’t duplicate. When Paul III took over the business in the 1960s, he began sending arrangements to television networks for use during their holiday specials. In a priceless bit of advertising, stars like Ronald Reagan, Dinah Shore, and Bob Hope were sharing screen time with the plant, leading millions of Americans to associate it with the holiday.

While the Ecke single-stem secret was eventually cracked by other florists—it involved grafting two stems to make one—and their market share dwindled, their innovative marketing ensured that the poinsettia would forever be linked to Christmas.

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Why Does Santa Claus Live at the North Pole?

allanswart/iStock via Getty Images
allanswart/iStock via Getty Images

As children settle in for a restless night’s sleep this Christmas Eve, they’ll no doubt be picturing Santa Claus on his way from the snowy ’scapes of the North Pole to deliver them Star Wars LEGO sets, Frozen 2 dolls, and everything else on their wish list. They picture Santa at the North Pole, of course, because they’ve seen him living there in numerous Christmas movies, books, and television specials, from perennial Rankin/Bass programs to more modern classics like 2003’s Elf.

While it might seem a little more magical if we told you that nobody really knows why Santa lives there, there is a relatively traceable paper trail: The first known reference to Santa’s North Pole residence is in an 1866 cartoon from Harper’s Weekly.

According to Smithsonian.com, famed political cartoonist Thomas Nast—who was also responsible for establishing the donkey and elephant as the symbols for the Democratic and Republican parties, respectively—first started creating Harper’s Weekly Christmas cartoons as Union propaganda for the Civil War in January 1863. Borrowing imagery from Clement Clarke Moore’s (alleged) 1823 poem “A Visit From St. Nicholas” (which you’d probably recognize as “’Twas the Night Before Christmas”), Nast developed the white-bearded, rosy-cheeked, all-around jolly guy that we know today, and showed him passing out gifts to Union soldiers, climbing into a chimney as a soldier’s wife prays, and more.

harper's weekly santa claus at camp by thomas nast
Thomas Nast, Harris Brisbane Dick Fund, Wikimedia Commons // Public Domain

The cartoons became so popular that Nast branched out from his source material and began inventing his own details to add to Saint Nick—like where he’s from, for example. A December 29, 1866 issue of Harper’s Weekly debuted a multi-image cartoon titled “Santa Claus and His Works,” which includes a small inscription along the circular border that reads Santa Claussville, N.P. According to The New York Times, we don’t know exactly why Nast chose the North Pole (or if it was even his own idea), but there are a few reasons it made sense for the time period.

For one, Santa Claus was already widely associated with snow because most of the publishing companies producing Christmas cards and other content were located in New England, where it actually snows around Christmas. Furthermore, the 1840s and 1850s were partly characterized by high-profile—and ill-fated, in the Franklin expedition's case—attempts to explore the Arctic, and the public was generally interested in the mysterious, poorly-charted region. Because the Pole was unoccupied, Santa and his elves could toil the year away without interference from prying eyes; and, because it was unclaimed, Santa could remain a bastion of benevolence for every nation.

merry old santa claus by thomas nast
"Merry Old Santa Claus," perhaps Nast's most famous illustration of Santa, from the January 1, 1881 edition of Harper's Weekly.
Thomas Nast, Wikimedia Commons // Public Domain

Though we’ll likely never know Nast’s personal rationale behind placing Santa Claus in the North Pole, one thing’s for sure: At this point, it’s hard to imagine him living anywhere else. It’s also hard to imagine him riding a broom, wielding a gun, or smoking cigarettes (find out the stories behind those early Santas here).

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