15 Explosive Facts About Volcanoes

U.S. Geological Survey via Getty Images
U.S. Geological Survey via Getty Images

On May 3, the Kilauea volcano erupted on Hawaii's Big Island. Since then, 18 fissures have opened in the earth, some hundreds of feet long. The USGS's Hawaii Volcano Observatory reports that some of these fissures are producing "lava fountaining, explosion of spatter bombs hundreds of feet into the air, and several advancing lava flow lobes." More than 2000 people have evacuated, and dozens of structures and vehicles have been destroyed. Five earthquakes have rattled the island as well.

Volcanoes are amazing portals to the hot, living interior of the Earth, but they're also dangerous. Even small-ish ones can have a global impact. Here are 15 explosive facts about volcanoes.

1. THE VOLCANIC EXPLOSIVITY INDEX MEASURES THE STRENGTH AND SIZE OF ERUPTIONS.

Created in 1982 by Chris Newhall of the United States Geological Survey and Stephen Self of the University of Hawaii, the VEI quantifies the strength of volcanic eruptions by measuring the volume of pyroclastic material spewed by a volcano, including volcanic ash, tephra (fragments of volcanic rock and lava), pyroclastic flows (fast-moving currents of gas and tephra), and other debris. The height and duration of the eruption are also factored in. The scale ranges from 1 to 8, and each step indicates a tenfold increase of ejecta. Fortunately, there hasn’t been a VEI-8 eruption in the past 10,000 years.

2. "WAH WAH SPRINGS" SOUNDS KIND OF FUN. IT WAS ACTUALLY DEVASTATING.

One of the biggest eruptions ever occurred about 30 million years ago in what is today eastern Nevada and western Utah, when a supervolcano exploded 3500 cubic kilometers of magma over an area of about 12,000 square miles. The eruption left behind deposits of debris 13,000 feet deep. Consider that the 1883 eruption of Krakatau, in Indonesia, was heard thousands of miles away—and yet it was a minor burp compared to Wah Wah Springs, a VEI-8 eruption.

3. LAVA IS THE LEAST OF YOUR WORRIES.

Garden of the Fugitives, Pompeii
Garden of the Fugitives, Pompeii

Lava generally moves too slowly to be the biggest threat from an eruption—but that’s not the case with pyroclastic flows. These super-hot, fast-moving currents of gas and tephra did in history’s most famous volcano victims: the residents of Herculaneum and Pompeii. The flow that hit Herculaneum was as hot at 500 degrees—enough to boil brains and vaporize flesh—while the later, cooler wave that hit Pompeii “cooked” people’s flesh, as the BBC puts it, but left their bodies intact; they were preserved by the falling volcanic ash.

4. JUST FOR FUN, THERE ARE 10 WAYS AN ERUPTION CAN KILL YOU.

As Io9 recounts, flying shrapnel, scalding-hot seawater, falling into a lava tube, poisonous gases, and volcanic smog, or vog, can also do you in.

5. THERE ARE THREE TYPES OF VOLCANIC ERUPTIONS.

Magmatic eruptions involve the decompression of gas within magma that propels it forward. Phreatic eruptions are driven by the heat from magma creating superheated steam. Phreatomagmatic eruptions are caused by the interaction of water and magma.

6. VOLCANOLOGISTS ARE CONTINUOUSLY KEEPING TABS ON ACTIVITY ALL OVER THE WORLD.

One of the many initiatives tracking potentially dangerous activity is the Global Volcanism Program of the Smithsonian National Museum of Natural History. It also puts out a weekly report in conjunction with the USGS that features a map. The International Association of Volcanology and Chemistry of the Earth's Interior (IAVCEI) especially monitors the so-called Decade Volcanoes—16 volcanoes that are potentially hazardous due to their history of large, destructive eruptions and proximity to populated areas. Among them are Rainier, Sakurajima, Vesuvius, and Santorini.

7. THERE ARE VOLCANOES ON OTHER PLANETS AND MOONS IN OUR SOLAR SYSTEM.

Plumes on Io captured by the Galileo spacecraft
Plumes on Io captured by the Galileo spacecraft
NASA/JPL/University of Arizona

That Jupiter’s moon Io is volcanically active has been known since 1979, when Voyager 1 imaging scientist Linda Morabito discovered the first evidence of active volcanism on a body other than Earth. But it’s far from alone. For instance, while Mars’s volcanoes appear to be either dormant or extinct, recent evidence from the Venus Express spacecraft suggests that many of Venus’s volcanoes are active.

8. SHARKS HANG OUT IN ONE VOLCANO.

Scientists recently recorded video of sharks happily swimming around in the acidic, hot, ash- and gas-filled waters near the Kavachi underwater volcano in the Solomon Islands, which is a mere 66 feet below the surface. This suggests extremophiles may be even more diverse than we thought.

9. THE USGS’s ALL-TIME BEST-SELLING MAP FEATURES VOLCANOES.

"This Dynamic Planet" is now in its third edition. This map [PDF] features more than 1500 volcanoes, 44,000 earthquakes, and 170 impact craters, as well as the major, minor, and micro tectonic plates whose movement creates these features. About 60 of Earth’s 550 historically active volcanoes blow every year.

10. AN EARLY 19TH-CENTURY ERUPTION IN THE PACIFIC WAS WORLD CHANGING.

Gillen D’Arcy Wood argues in his book Tambora: The Eruption That Changed the World that the 1815 eruption of the volcano on the Indonesian island of Sumbawa, which created a massive sulfate dust cloud that fundamentally altered the planet’s climate for three years, led to such diverse impacts as the first worldwide cholera pandemic, expanded opium markets in China, the U.S.’s first economic depression—and Mary Shelley’s Frankenstein.

11. A VOLCANO STAMP SOLD CONGRESS ON THE PANAMA CANAL.

Before the Panama Canal opened in 1915, rival proposals for an Atlantic–Pacific link included a plan to carve a canal through Nicaragua, which had a lot more fresh water and much less deadly malaria than Panama. It also has significant volcanic activity, and in the early 20th century, one of its stamps featured an erupting volcano. In 1902, just before a U.S. congressional vote, a pro-Panama Canal French engineer sent this stamp to all 90 senators to hype the volcanic threat in Nicaragua. Panama got the vote by a slim margin. Today Nicaragua says it’s building the canal with help from a Chinese funder.

12. SPEAKING OF NICARAGUA’S VOLCANOES—YOU CAN SURF ONE.

Cerro Negro, a new and very active volcano that first erupted in 1850—and has blown 23 times since, most recently in 1999—has black pebble-covered slopes you can surf down on a metal-bottomed wood board, if you're adventurous and also kind of insane. Intrigued? Here’s our 7-point guide to surfing volcanoes.

13. THE MOST VOLATILE AREA ON EARTH IS THE RING OF FIRE.

Located at the rim of the Pacific Basin, the so-called Ring of Fire is a nearly continuous chain of oceanic trenches and hundreds of volcanoes spanning some 25,000 miles that’s home to 75 percent of the world’s volcanic activity, with some 452 volcanoes (active and dormant), 90 percent of the world's earthquakes, and 22 of the 25 biggest volcanic eruptions in the last 11,700 years.

14. THERE ARE MANY WARNING SIGNS OF VOLCANIC ACTIVITY.

According to the USGS’s Volcano Hazards Program, volcanologists keep an eye out for ground movements caused by magma forcing its way upward through solid rock, earthquakes resulting from this heaving, and changes in heat output and volcanic gases. Other indicators include cracks in the ground, small steam explosions, melting snow, and the appearance of new hot springs.

15. YOUR EUROPE FLIGHT WAS DELAYED IN 2010 BECAUSE OF AN ICELANDIC ERUPTION.

The Eyjafjallajökull volcano began erupting on April 14, 2010 and didn’t stop for six weeks, spewing magma, ash, and gas. Planes were grounded across Europe. Though the eruption was a small one, it had an outsized impact because it spread unusually far and stayed for an unexpectedly long time in the atmosphere thanks to the irregular shape of the tiny porous ash grains, as LiveScience reports.

BONUS: NASA IS TRAINING FOR LIFE ON MARS ON THE SLOPES OF AN ACTIVE VOLCANO.

For several years, NASA has been simulating life on Mars through a simulation on the slopes of Hawaii's Mauna Loa volcano, one of the Decade Volcanoes. Each year, a small team of adventurers who meet the basic qualifications for the NASA astronaut program live in a solar-powered geodesic dome. If they want to go outside, they have to put on space suits. Still beats trying to escape poisonous gases and pyroclastic flows.

5 Signs Humans Are Still Evolving

Lealisa Westerhoff, AFP/Getty Images
Lealisa Westerhoff, AFP/Getty Images

When we think of human evolution, our minds wander back to the millions of years it took natural selection to produce modern-day man. Recent research suggests that, despite modern technology and industrialization, humans continue to evolve. "It is a common misunderstanding that evolution took place a long time ago, and that to understand ourselves we must look back to the hunter-gatherer days of humans," Dr. Virpi Lummaa, a professor at the University of Turku, told Gizmodo.

But not only are we still evolving, we're doing so even faster than before. In the last 10,000 years, the pace of our evolution has sped up, creating more mutations in our genes, and more natural selections from those mutations. Here are some clues that show humans are continuing to evolve.

1. Humans drink milk.

Historically, the gene that regulated humans' ability to digest lactose shut down as we were weaned off our mothers' breast milk. But when we began domesticating cows, sheep, and goats, being able to drink milk became a nutritionally advantageous quality, and people with the genetic mutation that allowed them to digest lactose were better able to propagate their genes.

The gene was first identified in 2002 in a population of northern Europeans that lived between 6000 and 5000 years ago. The genetic mutation for digesting milk is now carried by more than 95 percent of northern European descendants. In addition, a 2006 study suggests this tolerance for lactose developed again, independently of the European population, 3000 years ago in East Africa.

2. We're losing our wisdom teeth.

Our ancestors had much bigger jaws than we do, which helped them chew a tough diet of roots, nuts, and leaves. And what meat they ate they tore apart with their teeth, all of which led to worn-down chompers that needed replacing. Enter the wisdom teeth: A third set of molars is believed to be the evolutionary answer to accommodate our ancestors' eating habits.

Today, we have utensils to cut our food. Our meals are softer and easier to chew, and our jaws are much smaller, which is why wisdom teeth are often impacted when they come in — there just isn't room for them. Unlike the appendix, wisdom teeth have become vestigial organs. One estimate says 35 percent of the population is born without wisdom teeth, and some say they may disappear altogether.

3. We're resisting infectious diseases.

In 2007, a group of researchers looking for signs of recent evolution identified 1800 genes that have only become prevalent in humans in the last 40,000 years, many of which are devoted to fighting infectious diseases like malaria. More than a dozen new genetic variants for fighting malaria are spreading rapidly among Africans. Another study found that natural selection has favored city-dwellers. Living in cities has produced a genetic variant that allows us to be more resistant to diseases like tuberculosis and leprosy. "This seems to be an elegant example of evolution in action," says Dr. Ian Barnes, an evolutionary biologist at London's Natural History Museum, said in 2010 statement. "It flags up the importance of a very recent aspect of our evolution as a species, the development of cities as a selective force."

4. Our brains are shrinking.

While we may like to believe our big brains make us smarter than the rest of the animal world, our brains have actually been shrinking over the last 30,000 years. The average volume of the human brain has decreased from 1500 cubic centimeters to 1350 cubic centimeters, which is an amount equivalent to the size of a tennis ball.

There are several different conclusions as to why this is: One group of researchers suspects our shrinking brains mean we are in fact getting dumber. Historically, brain size decreased as societies became larger and more complex, suggesting that the safety net of modern society negated the correlation between intelligence and survival. But another, more encouraging theory says our brains are shrinking not because we're getting dumber, but because smaller brains are more efficient. This theory suggests that, as they shrink, our brains are being rewired to work faster but take up less room. There's also a theory that smaller brains are an evolutionary advantage because they make us less aggressive beings, allowing us to work together to solve problems, rather than tear each other to shreds.

5. Some of us have blue eyes.

Originally, we all had brown eyes. But about 10,000 years ago, someone who lived near the Black Sea developed a genetic mutation that turned brown eyes blue. While the reason blue eyes have persisted remains a bit of a mystery, one theory is that they act as a sort of paternity test. “There is strong evolutionary pressure for a man not to invest his paternal resources in another man’s child,” Bruno Laeng, lead author of a 2006 study on the development of blue eyes, told The New York Times. Because it is virtually impossible for two blue-eyed mates to create a brown-eyed baby, our blue-eyed male ancestors may have sought out blue-eyed mates as a way of ensuring fidelity. This would partially explain why, in a recent study, blue-eyed men rated blue-eyed women as more attractive compared to brown-eyed women, whereas females and brown-eyed men expressed no preference.

Now Ear This: A New App Can Detect a Child's Ear Infection

iStock.com/Techin24
iStock.com/Techin24

Generally speaking, using an internet connection to diagnose a medical condition is rarely recommended. But technology is getting better at outpacing skepticism over handheld devices guiding decisions and suggesting treatment relating to health care. The most recent example is an app that promises to identify one of the key symptoms of ear infections in kids.

The Associated Press reports that researchers at the University of Washington are close to finalizing an app that would allow a parent to assess whether or not their child has an ear infection using their phone, some paper, and some soft noises. A small piece of paper is folded into a funnel shape and inserted into the ear canal to focus the app's sounds (which resemble bird chirps) toward the child’s ear. The app measures sound waves bouncing off the eardrum. If pus or fluid is present, the sound waves will be altered, indicating a possible infection. The parent would then receive a text from the app notifying them of the presence of buildup in the middle ear.

The University of Washington tested the efficacy of the app by evaluating roughly 50 patients scheduled to undergo ear surgery at Seattle Children’s Hospital. The app was able to identify fluid in patients' ears about 85 percent of the time. That’s roughly as well as traditional exams, which involve visual identification as well as specialized acoustic devices.

While the system looks promising, not all cases of fluid in the ear are the result of infections or require medical attention. Parents would need to evaluate other symptoms, such as fever, if they intend to use the app to decide whether or not to seek medical attention. It may prove most beneficial in children with persistent fluid accumulation, a condition that needs to be monitored over the course of months when deciding whether a drain tube needs to be placed. Checking for fluid at home would save both time and money compared to repeated visits to a physician.

The app does not yet have Food and Drug Administration (FDA) approval and there is no timetable for when it might be commercially available. If it passes muster, it would join a number of FDA-approved “smart” medical diagnostic tools, including the AliveKor CardiaBand for the Apple Watch, which conducts EKG monitoring for heart irregularities.

[h/t WGRZ]

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