Volcanoes • Vol. 19: #6 • (2-5-2023) Tidbits of Coachella Valley

At any given moment, about 20 volcanoes are exploding somewhere around the world. Approximately 350 million people live within “danger range” of an active volcano, the high-risk area for human casualties in the event of an eruption. Follow along as Tidbits peers into these ruptures in the Earth's crust to see what we can learn.

VOLCANO FACTS

• Did you know that one of the most potentially dangerous volcanoes on Earth lies in the northwest corner of Wyoming, just beneath the surface of Yellowstone National Park? In fact, the park itself is actually located in the caldera of an ancient -- but still active -- supervolcano. After Yellowstone last erupted many millennia past, it left a crater on the surface larger than the state of Rhode Island. The entire area is rising steadily at the rate of a half-inch per year, as activity continues directly belowground. Yellowstone is one of about 30 “hot spots” in the Earth’s crust with supervolcano potential.

Yellowstone National Park, with its awesome beauty, sits atop a so-called super volcano.

• The reason potatoes grow so well in Idaho today is because Mt. Mazama erupted 6,600 years ago, spreading mineral-rich ash over the entire area. Today Mt. Mazama is known as Crater Lake. When the volcano was exhausted, the empty magma chambers collapsed upon themselves, and the deep volcanic crater filled with water.

Water filled in Mt. Mazama's empty magma chambers forming Crater Lake, in Idaho.

• “Magma” is molten rock that’s still underground, while “lava” is molten rock that’s been expelled and is above the surface.

CATACLYSMIC ERUPTIONS

• On April 5, 1815, the Lieutenant Governor of Java in Indonesia heard what he thought was loud, booming cannon fire coming across the ocean. Thinking a ship might be in distress, he immediately dispatched two ships to search the Java Sea to find out what could have happened. He also ordered a detachment of troops to march into the city just in case rebels were attacking a nearby outpost. The ships found nothing during their search and no rebels appeared in town. Days later news reached Java that the volcanic mountain of Tambora, on an island 750 miles away, had exploded and destroyed itself. The enormous sound had traveled that far.

• The gas and dust from the Tambora explosion soon circled the entire globe, causing extreme weather and unusual cold worldwide. A 19-yearold woman named Mary Wollstonecraft Shelley was vacationing in Switzerland that summer. Since the sunshine was blocked making it too cold to go outside to enjoy the mountains, she stayed inside instead and began writing a novel she called “Frankenstein.”

• When Mount Pinatubo in the Philippines erupted in 1991, global temperatures fell by an average of half a degree Fahrenheit. The volcano released some 30 million metric tons of sulfur dioxide into the stratosphere. The highly reflective particles bounced sunlight back into space. The sulfates circulated for about a year before eventually dissipating.

Volcanic ash billows into the sky during Mount Pinatubo's violent eruption in the Philippines, in 1991.

• On August 26, 1883, Mt. Krakatoa erupted in a massive explosion on the coast of Indonesia. It’s thought that an earthquake opened a rift in the side of the volcano which allowed cold sea water to rush into the hot magma chambers. This resulted in a series of cataclysmic eruptions and catastrophes that lasted all day, all night, and into the next day. The blast was equal to 10,000 Hiroshima-size atom bombs, and some 20 times more powerful than the 1981 Mount Saint Helens blast. Sailors at sea more than 60 miles away suffered permanent hearing damage from the intense concussion. It’s said to have been the loudest sound ever heard on Earth in human history.

A world map showing the Indian Ocean region impacted by Mt. Krakatoa's massive explosion in 1883.

• In El Salvador, the mountain called Volcan Izalco had been erupting almost constantly for years. The government decided money could be made by opening the place to tourists. So they declared it a national park, paved a road, built a hotel, a bar, and a restaurant, and announced the grand opening. As the ribbons were being cut, the volcano stopped erupting. It has been dormant ever since.

FIRE AND ICE

• In 1973, the Helgafell volcano off the coast of Iceland began erupting. The 5,300 residents of the island were evacuated, but 300 determined people stayed to try to save the town from the slowly advancing lava. The huge 120-foottall, 1,000-foot-wide wall of creeping lava threatened to completely seal off the town’s only harbor, ruining many industries that depended on access to the ocean, and destroying the town’s commercial value.

• In desperation, their fire engines pumped water on the advancing flow. Small tongues of lava solidified under the steady barrage of water, and a small dam built up, slowing the flow. Then a sand dredger with Iceland’s most powerful pumps started spewing tons of sea water onto the flow. Workers found that by piping the water to a point behind the flow’s front, a series of small dams formed internal barriers in the flow. Plastic pipes laid on top of the hot rock would not melt as long as the cold seawater continued to flow through them.

• 19 miles of pipes and 43 pumps were used to continuously pump water for nearly four months straight. Finally, the volcano settled down. Many homes and businesses had been permanently lost, but the harbor -- and most of the town -- had been spared.

HAWAII FACTS

• There is a hot spot in the Earth’s crust that meanders beneath the islands of Hawaii. It periodically allows magma to escape, building new land. The hot spot remains in one place, but continental drift causes the plate of the earth’s crust to slowly float over it. Over many millennia this geologic phenomenon has resulted in the building up of Hawaii’s chain of islands, one at a time.

• The volcanic mountain named Mauna Loa in Hawaii is the tallest mountain in the world if you include its entire slope that continues down another 16,400 feet below the surface to the seabed. Mauna Loa is 30,080 feet tall from its base to the peak (that’s 5.7 miles), and it’s still growing. In comparison, Mt. Everest only rises to 29,032 feet.

Hawaii's volcanic mountain, Mauna Loa, is 30,080 feet tall from its peak to its base located on the ocean floor (16,400 below the surface).

• Kilauea Crater in Hawaii is one of the world’s most active volcanoes, erupting regularly about once a month. The sugar cane fields belonging to the Ola Sugar Co. were once being destroyed by a wall of advancing lava. Their New York insurance company refused to pay for damages, claiming that the crop was insured against fire, not lava. The Ola Sugar Co. insisted that a claims agent fly out to Hawaii to look at the situation firsthand. The agent, having never before seen a lava flow, was very nervous as he was driven closer and closer to the lava activity. It was explained to him as he became increasingly frightened that the heat from the advancing lava was so intense that it first burned the crop before covering it. As a fountain of lava suddenly burped up near the car, the agent agreed to pay the claim if only they would just get him out of that place!

PARTING FACTS

• “Volcano” comes from Vulcan, the Roman god of fire. “Crater” is Latin for “cup.”

• “Lava” comes from the Latin word meaning “to wash” which also gives us “lavage” and “lavatory.” The word originally meant a downpour of rain that washed the streets, but later came to mean a flow of melted rock that scoured the mountainside clean of plants and trees. □

NUGGETS OF KNOWLEDGE

On April Fool's Day in 1980, as reports were in the news that an eruption of Mt. St. Helens was immanent, a TV reporter in Massachussetts thought it would be funny to air the report that a local non-volcanic ski hill was also about to erupt. Police were innundated with panicked phone calls from frightened citizens. The station apologized for the prank and the reporter was fired.