Most of the World’s Population Lives Within This 2500-Mile Radius

Prof Kenneth Myers
Prof Kenneth Myers

The Earth gets more crowded each year. In just the past decade, the planet has welcomed about 1 billion new residents. The biggest contributors to the booming population are a handful of countries, and most of them fall within a 2500-mile radius.

As friend of Mental Floss Ken Jennings writes for Condé Nast Traveler, the Valeriepieris circle covers more than half the world’s population. China and India, the world’s two most populous nations, plus Indonesia (the fourth) and Pakistan (the sixth), are all part of a section of Earth that stretches 2500 miles in all directions from a central point near Hainan, China's southernmost area. Bangladesh, Japan, the Philippines, and Vietnam, which all place in the top 15 most populous countries, are also included.

Not only are the populations of these places high, they’re also dense. In Bangladesh’s capital of Dhaka, for instance, every square mile holds about 115,000 citizens. (For comparison, New York City, America's most densely populated city, counts roughly 27,000 per square mile.) That explains how this circle can house billions of humans while also containing a lot of open ocean and empty desert.

The Valeriepieris circle is named after the American Reddit user who first shared the map in 2013. His real name is Ken Myers, and he was inspired to create the graphic after visiting Manila in the Philippines for a teaching fellowship and seeing firsthand how many people were crammed into the tight area. The math was checked by Singapore economics professor Danny Quah years later, and he found that Myers had actually been generous with his calculations. Narrow down the circle to a 2050 mile radius, with Mong Khet in Myanmar as the center point, and it still fits close to half the world’s people.

[h/t Condé Nast Traveler]

Amazon's Under-the-Radar Coupon Page Features Deals on Home Goods, Electronics, and Groceries

Stock Catalog, Flickr // CC BY 2.0
Stock Catalog, Flickr // CC BY 2.0

This article contains affiliate links to products selected by our editors. Mental Floss may receive a commission for purchases made through these links.

Now that Prime Day is over, and with Black Friday and Cyber Monday still a few weeks away, online deals may seem harder to come by. And while it can be a hassle to scour the internet for promo codes, buy-one-get-one deals, and flash sales, Amazon actually has an extensive coupon page you might not know about that features deals to look through every day.

As pointed out by People, the coupon page breaks deals down by categories, like electronics, home & kitchen, and groceries (the coupons even work with SNAP benefits). Since most of the deals revolve around the essentials, it's easy to stock up on items like Cottonelle toilet paper, Tide Pods, Cascade dishwasher detergent, and a 50 pack of surgical masks whenever you're running low.

But the low prices don't just stop at necessities. If you’re looking for the best deal on headphones, all you have to do is go to the electronics coupon page and it will bring up a deal on these COWIN E7 PRO noise-canceling headphones, which are now $80, thanks to a $10 coupon you could have missed.

Alternatively, if you are looking for deals on specific brands, you can search for their coupons from the page. So if you've had your eye on the Homall S-Racer gaming chair, you’ll find there's currently a coupon that saves you 5 percent, thanks to a simple search.

To discover all the deals you have been missing out on, head over to the Amazon Coupons page.

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How African Dust Storms Create the Caribbean’s Beautiful Beaches—and Protect Them from Hurricanes

Cam Green/Pexels
Cam Green/Pexels

The fertile red soils of Bermuda and the rich coral reefs of the Bahamas are a geological mystery. Both are made up of a specific combination of alien minerals and nutrients not found anywhere on the islands or in the ocean that surrounds them. Scientifically speaking, they should not exist.

But over the last decade, geologists have come up with an explanation for these ecological anomalies: They originated 5000 miles away in Africa. For more than a million years, dust from the Sahara Desert has hitched a ride on westward-traveling winds to the Caribbean. Bermuda and the Bahamas are, quite literally, an extension of the world’s largest desert.

But African dust storms aren’t just responsible for developing Bermuda’s clay-and-iron-abundant “terra rossa” and the coral reefs of the Bahamas; they also play an important role in protecting them from destructive hurricanes. Like atmospheric superheroes, the dust storms’ combination of dry air, strong winds, and cloud-suppressing particles appears to have the ability to stop hurricanes in their tracks.

From Desert to Tropical Paradise

On June 18, 2020, NASA-NOAA’s Suomi NPP satellite captured this visible image of the large light brown plume of Saharan dust over the North Atlantic Ocean. NASA Worldview // Public Domain

In the summer months, dust storms, some as large as the continental United States, roll off the African coast every three to five days in a dry atmospheric shelf called the Saharan Air Layer. Sometimes they dissipate before they reach the eastern Atlantic. Other times, like in late June and early July 2020, they set sunsets afire from the Caribbean to the southeastern U.S.

The dust blown to Earth by these long-haul storms is packed with soil-enriching nutrients and iron that have completely altered parts of the natural landscape. Bermuda’s endemic dirt and sand is made up of the calcium carbonate leftovers of ancient coral, mollusks, and crustaceans, and the growth of abundant plant matter would be impossible without nutrient deposits from annual African dust storms.

Researchers hypothesize that the Bahamas’s underlying layer of calcium-rich rock and coral reefs wouldn’t have developed without Saharan dust, either—the dust is thought to help cyanobacteria fix nitrogen in the environment, allowing the carbonate layers to accumulate.

Hurricane-Smothering Sands

Climate scientists believe that Saharan dust storms may have an equally important job high above Earth. The summer dust storm season closely coincides with tropical storm and hurricane season, and most of them—around half of all tropical storms and 85 percent of the Atlantic’s most intense hurricanes—originate in Africa.

As they hurtle westward, hurricanes and dust storms mix it up over the Atlantic. But it’s not a fair fight. Hurricanes need humid air to form; dust storms are extremely dry. Hurricanes suck up moisture from the ocean and then release it as rain, while dust prevents moisture from rising into the atmosphere’s higher layers. Dust storms also have "vertical wind shear,” strong embedded winds that can break down a developing hurricane. Essentially, a Saharan dust storm is like a bone-dry, extremely powerful, hurricane-smothering blanket.

As hurricanes increase in frequency and strength alongside warming oceans and a changing climate, understanding exactly how they interact with dust storms may help researchers to identify which Atlantic storms are the most likely to intensify into life-threatening hurricanes. And if climate scientists can recognize the most destructive storms far in advance, those in their path may have a better chance of emerging unscathed when gray skies return to blue.