January 13, 2020

Earth has been a particularly dangerous place in recent weeks. Airplane crashes, military clashes, terror attacks, and political unrest have taken a toll on human life and happiness lately, but it is a series of natural disasters that has caused the most trouble. A typhoon ravaged the Philippines, deadly flash floods hit Indonesia, bushfires continued to rage in Australia, a measles epidemic continued to kill in the Democratic Republic of the Congo, and a series of earthquakes rattled Puerto Rico.

Firefighters confront a bushfire near the Blue Mountains town of Bilpin, New South Wales, on Dec. 19, 2019. Credit: © 1234rf/Shutterstock

On Christmas Eve and Christmas Day Typhoon Phanfone (also called Ursula) struck the Philippines, producing high winds and flooding that killed 105 people in the Visayan Island provinces of Biliran, Capiz, Iloilo, and Leyte. Phanfone was a Category 2 storm (moderate strength) with sustained winds of more than 90 miles (150 kilometers) per hour. Storm surges and deadly flash floods hit communities just as families were gathering to celebrate the Christmas holiday. Thousands of homes were damaged or destroyed.

On New Year’s Day in Indonesia, abnormally heavy monsoon rains caused flash floods that killed 66 people and displaced hundreds of thousands of others in Jakarta, the capital. Some 14.5 inches (37 centimeters) of rain fell on New Year’s Eve, causing the Ciliwung and Cisadane rivers to overflow. Floodwaters submerged more than 150 neighborhoods and caused landslides in the Bogor and Depok districts on the outskirts of Jakarta. Flood water levels in some areas peaked at more than 13 feet (4 meters). Electric power was cut off, and closed schools and government buildings were converted into emergency shelters.

On January 7, the World Health Organization announced the 6,000th death from measles in the Democratic Republic of the Congo (DRC) since an epidemic began there in 2019. More than 300,000 suspected measles cases have been reported in the DRC—a nation also troubled by recent terror attacks. The epidemic has continued and grown because of low vaccination coverage, malnutrition, weak public health systems, outbreaks of other epidemic-prone diseases (such as Ebola), and the difficulty of getting health care to people in remote areas.

In Puerto Rico, after several smaller earthquakes, a 6.4-magnitude temblor struck the southwestern part of the island on January 7. The earthquake, the strongest to hit Puerto Rico in more than 100 years, killed one person, toppled hundreds of structures, and forced a state of emergency. Many people lost their homes, the island briefly lost electric power, and schools and public offices were closed. In the 10 days before the 6.4-magnitude earthquake, the United States Geological Survey recorded hundreds of temblors in Puerto Rico—including 10 of 4-magnitude or greater.

A number of major bushfires have lately devastated southeastern Australia. Since September, the wild fires—mostly in New South Wales, Queensland, and Victoria—have burned more than 25.5 million acres (10.3 million hectares), an area the size of South Korea. The bushfires have destroyed more than 2,100 homes and killed 27 people and hundreds of millions of animals. On January 8, the Australian government ordered the mass slaughter of thousands of wild camels and horses that have invaded rural towns looking for water. Many people are without electric power and telecommunications in Australia’s southeast, and some were without drinking water and other supplies. Smoke has obscured the city skies of Canberra, Melbourne, and Sydney. The bushfires followed a three-year drought that experts link to climate change.

August 10, 2018

Early on July 29 in southern Indonesia (July 28 in the United States), a 6.4-magnitude earthquake destroyed buildings and killed 17 people on the small island of Lombok. As bad as that was, it proved to be only a warning shot. A week later, on the evening of August 5, a second, stronger earthquake struck the island, and this one, a 6.9-magnitude temblor, proved to be much more destructive. The earthquake collapsed numerous buildings already weakened by the earlier quake, and thus far the dead bodies of 259 people have been pulled from the rubble. Thousands of people have been injured in the disaster, and tens of thousands more have been left homeless.

A man searches through the ruins of houses in Pemenang village in northern Lombok on Aug. 7, 2018, two days after a powerful earthquake devastated the area. Credit: © Sonny Tumbelaka, AFP/Getty Images

Lombok is a lovely tropical island popular with tourists. Only about 40 miles (60 kilometers) across, Lombok sits between the islands of Bali and Sumbawa among Indonesia’s Lesser Sunda Islands. More than 3 million people live on Lombok, and tens of thousands of tourists visit the island every year. Lombok has beautiful beaches, highland forests, and a mountainous interior dominated by Mount Rinjani, an active volcano. Lombok lies at the junction of tectonic plates, however, making it prone to earthquakes. Much of Indonesia sits on the infamous Ring of Fire, a turbulent zone of frequent seismic and volcanic activity along the islands and continents rimming the Pacific Ocean.

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Lombok lies just east of Bali in the Lesser Sunda Islands of southern Indonesia. Credit: WORLD BOOK map

On July 29, the 6.4-magnitude earthquake struck Lombok’s northern coast near Mount Rinjani. The earth shook violently near the epicenter for more than 10 seconds, knocking buildings to the ground and causing landslides along the slopes of the volcano. Seventeen people died in the earthquake, and hundreds of hikers were briefly stranded in Mount Rinjani National Park. Some 1,000 buildings were damaged or destroyed.

On August 5, as people were still cleaning up from the earlier earthquake, the 6.9-magnitude temblor hit in almost the exact same location. Structures collapsed throughout the island, including in the provincial capital of Mataram near Lombok’s west coast. Terrified people fled to soundly built mosques as aftershocks continued, and a tsunami warning caused panic in low-lying coastal areas. No tsunami occurred, but damage from the earthquake was significant. More than 40,000 buildings were damaged or destroyed on Lombok (including several mosques), electric power and communications systems were knocked out, and three bridges collapsed. The death toll stands at 259, but many people remain missing, so that number will almost certainly rise.

Hundreds of aftershocks have since shaken Lombok, the strongest of which, a 5.9-magnitude temblor, hit early on August 9 (August 8 in the United States), causing still more damage and further frightening the population.

The more than 150,000 people left homeless by the earthquakes are now in need of shelter, food, clean water, and medical supplies, but aid is pouring in from elsewhere in Indonesia and from around the world. Several thousand tourists were forced to evacuate resorts and hotels and leave the island. The Lombok temblor was the deadliest to hit the Lesser Sunda Islands since December 1992, when an earthquake and tsunami killed more than 2,000 people on Flores island east of Sumbawa.

September 21, 2017

Two days ago, on September 19, a powerful 7.1-magnitude earthquake struck central Mexico, collapsing buildings and killing more than 240 people in Mexico City, the capital, and in the states of Guerrero, México, Morelos, Oaxaca, and Puebla. The earthquake struck on the anniversary of a catastrophic 1985 earthquake that killed some 10,000 people in central Mexico. The quake followed another deadly temblor that hit southern Mexico earlier in September 2017.

Rescue workers call for quiet as they search a collapsed building in the Mexico City neighborhood of La Condesa following a powerful 7.1-magnitude earthquake on Sept. 19, 2017. The earthquake toppled buildings and killed more than 240 people in the region. Credit: © Alejandro Cegarra, Bloomberg/Getty Images

The earthquake’s epicenter was near the small Puebla city of Atencingo, about 75 miles (120 kilometers) southeast of Mexico City. The prolonged tremor hit at 1:14 p.m. local time—just two hours after an annual earthquake drill in Mexico City—shaking buildings and frightening people into the streets. Structures collapsed in several cities, obscuring the panicked survivors in dust clouds amid the blaring din of alarm sirens.

Emergency responders rushed to the first scenes of destruction. Unstable rubble and electric power outages hampered rescue efforts, and widespread damage meant many ravaged places went hours without help. Military personnel and civilian volunteers aided emergency workers as they searched through the night for survivors. Sniffer dogs followed human scents, and workers pleaded for silence, hoping to hear the calls of people trapped beneath the destruction. Many people were saved, but the body count rose quickly as splintered wood, shattered masonry, and chunks of concrete were frantically removed. Many people remain missing amid the devastation, and the disaster’s death toll—245 as of this morning—will almost certainly rise.

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On Sept. 19, 2017, a powerful earthquake hit central Mexico, killing more than 240 people in the Federal District of Mexico City and in the states of Guerrero, México, Morelos, Oaxaca, and Puebla. Credit: WORLD BOOK map

In Mexico City, more than 90 people have died, including 21 children and 5 adults killed when an elementary school collapsed in the city’s southern Coapa district. More than 70 people were killed in Morelos, just south of Mexico City, and more than 40 died in the epicenter state of Puebla. On the slopes of Popocatépetl volcano southeast of Mexico City, a church collapsed in the village of Atzitzihuacán, killing 15 people. Throughout the region, scores of buildings fell, ruptured gas lines sparked fires, and falling debris crushed cars on the streets.

Like the earthquake earlier in September in southern Mexico, Tuesday’s temblor struck near the Middle America Trench, a zone in the eastern Pacific Ocean where one slab of Earth’s crust, the Cocos Plate, is sliding beneath the North American Plate—a geological process called subduction. The Middle America Trench is part of the so-called Ring of Fire, an area of high seismic and volcanic activity that encircles the Pacific Ocean. The United States Geological Survey (USGS) issued an orange alert (the second-highest threat level) after Tuesday afternoon’s quake, warning of significant casualties and extensive and widespread damage. The alert was part of the USGS PAGER (Prompt Assessment of Global Earthquakes for Response) system that informs emergency responders, the media, and government and aid agencies of the scope of a potential disaster.

On Sept. 19, 1985, an 8.0-magnitude temblor killed some 10,000 people in Mexico City and nearby areas. About 400 buildings in the capital were destroyed in that disaster, and thousands of others suffered damage. Since then, Mexico has enacted tougher building codes and safety standards—moves that no doubt saved many lives 32 years later.

September 12, 2017

Just before midnight on Thursday, September 7, a powerful earthquake caused death and destruction in southern Mexico. The 8.1-magnitude quake, the strongest in the region in decades, centered just off the Pacific coast states of Chiapas and Oaxaca. The temblor (another word for earthquake in both English and Spanish) toppled numerous structures and killed 96 people. Many people remain missing, however, and the death toll will almost certainly rise.

Emergency crews search the collapsed ruins of buildings in Juchitán de Zaragoza, Mexico, after a powerful earthquake struck the area late on Sept. 7, 2017. At left stand the surviving white arches of the city’s damaged palacio municipal (city hall). Credit: © Pedro Pardo, AFP/Getty Images

The earthquake’s epicenter was in the Gulf of Tehuantepec just off the southern Mexican coast. The coastal city of Juchitán de Zaragoza bore the brunt of the earthquake’s destruction. Hundreds of buildings were destroyed there, and many thousands were damaged, including Juchitán’s historic palacio municipal (city hall). In the early hours of Friday, September 8, emergency crews, federal police, and soldiers began pulling the dead and the living from the rubble of wrecked buildings as aftershocks rocked the area, causing further damage and panic. Since then, many damaged buildings have been cleared, but strong aftershocks continue and many structures remain too unstable to enter. More than 160 area municipalities have declared states of emergency, and many thousands of people still lack electric power, running water, and phone service.

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Late on Sept. 7, 2017, a powerful earthquake caused damage and killed people in the southern Mexican states of Oaxaca, Chiapas, and Tabasco. Credit: WORLD BOOK map

The quake struck near the Middle America Trench, a zone in the eastern Pacific Ocean where one slab of Earth’s crust, the Cocos Plate, is sliding beneath the North American Plate—a geological process called subduction. The Middle America Trench is part of the so-called Ring of Fire, an area of high seismic and volcanic activity that encircles the Pacific Ocean. The United States Geological Survey (USGS) issued a red alert (highest threat level) after Thursday night’s quake, warning: “High casualties and extensive damage are probable and the disaster is likely widespread.” The alert was part of the USGS PAGER (Prompt Assessment of Global Earthquakes for Response) system that informs emergency responders, the media, and government and aid agencies of the scope of a potential disaster.

Last week’s earthquake was felt throughout southern Mexico and neighboring Guatemala. Some 500 miles (800 kilometers) away in Mexico City, the capital, structures swayed and earthquake alarms caused a mild panic. Many of the city’s residents carry vivid memories of the deadliest quake in Mexican history, an 8.0-magnitude temblor in 1985 that killed some 10,000 people in the city and nearby areas. About 400 buildings in Mexico City were destroyed in that disaster, and thousands of others suffered damage. Since then, Mexico has enacted tougher building codes and safety standards.

August 26, 2016

Two days ago, on August 24, a 6.2-magnitude earthquake shook the mountains of central Italy. The earthquake struck in the early morning, toppling homes and buildings in the region of Latium (often called Lazio) and causing damage in nearby Marche (or Marches) and Umbria as well. The earthquake killed 278 people and several people remain missing. About 400 people were injured. The mountain towns hit by the quake are popular with tourists, and many of the dead were travelers staying in hotels and hostels. Because many of the missing people are not residents, authorities are not sure how many people may yet be found buried in the devastation.

Survivors and rescue workers begin searching the ruins of Amatrice, Italy, after an earthquake struck on Aug. 24, 2016. Credit: © Antonio Nardelli, Shutterstock

The earthquake struck at 3:36 a.m. local time and centered near the mountain village of Amatrice, about 85 miles (140 kilometers) east of Rome, the Italian capital. The quake reduced much of the town to ruins, including several historic buildings dating from the 1400’s. The majority of the earthquake victims were in Amatrice, but scores died in such nearby villages as Accumoli, Arquata del Tronto, and Pescara del Tronto. The earthquake woke startled residents in Rome, and was felt as far away as Bologna to the north and Naples to the south. In the first 12 hours after the initial quake, the region trembled through some 150 aftershocks, the strongest of which measured 5.5 on the Richter scale. Survivors stumbled about the destruction, helping those who could be reached, and huddled in vehicles and tents as rescue workers arrived on the scene. Helicopters carried rescue workers to the area’s more isolated villages to retrieve survivors trapped by landslides and rubble.

This map shows the location of the earthquake that devastated Amatrice and other mountain towns in central Italy on Aug. 24, 2016. Credit: WORLD BOOK map

Amatrice has a population of about 2,000 people, but that number swells many times during the summer tourist season. Last year, Amatrice was voted one of Italy’s most beautiful historic towns, and the town’s popular spaghetti festival was scheduled for this weekend. Amatrice’s heartbroken mayor, Sergio Pirozzi, surveyed the destruction, saying, “The town is no more.”

Wednesday’s earthquake was the worst in Italy since 2009 when 308 people died in a powerful quake just south of Amatrice in the region of Abruzzo. That earthquake destroyed parts of the medieval city of L’Aquila. Italy sits on a major fault line, making it one of the most seismically active areas of Europe.

April 18, 2016

Most of the world’s earthquakes occur in the area of the Pacific Ocean known as the Ring of Fire. Both Japan and Ecuador are located in this seismically active region. Credit: WORLD BOOK map

Deadly earthquakes struck in Asia and South America over the last few days. In Japan, an earthquake with a magnitude of 6.2 struck the island of Kyushu on Thursday, April 14. Another 7.0-magnitude earthquake struck the same island two days later. Nine people were killed in the April 14 earthquake and more than 30 people died on April 16. After the second quake, heavy storms began in Japan, hampering rescuers racing to save people buried in landslides. Another earthquake—an aftershock—with a magnitude of 5.3 shook Japan today.

On April 16, Ecuador experienced a 7.8-magnitude earthquake. More than 300 people died in this quake. Although the strength of the Japan and Ecuador earthquakes may seem similar, because of how Richter magnitude is computed, each number on the Richter Scale represents a release of about 32 times the energy represented by the next lowest number. At a magnitude of 7.8, the Ecuador earthquake was about 20 times stronger than the 7.0-magnitude quake in Japan on April 16.

Both Japan and Ecuador are located on the Ring of Fire, a seismically active section of Earth created by the movement of tectonic plates. Experts state, however, that the Japan and Ecuador earthquakes were unrelated events. The areas are 9,000 miles ( 14,484 kilometers) apart, and they experienced different types of earthquakes. The earthquakes in Japan were of the strike-slip variety at a fault line (a break in Earth’s crust). In Ecuador, the quake was caused by tectonic plate activity at a subduction zone, where the Nazca Plate is slipping beneath the South America Plate.

August 25, 2014

A magnitude-6.0 earthquake struck Napa Valley—a famous wine-growing region of California—early yesterday morning. It was the most powerful earthquake to affect the area in 25 years. There were no fatalities in the quake, but more than 100 people were injured. A score of buildings in the older, central area of the town of Napa were badly damaged. In addition,  water mains were broken, and thousands of people were without electric power.

Napa Valley specializes in wineries, some of which lost valuable inventory to an earthquake on August 24. (Fred Lyon)

The worst-hit segment of the region was Napa Valley’s wineries. There are hundreds of wineries in the valley, producing some of the world’s premium wine. California’s wine industry was already struggling because of weather-related conditions. The drought of 2014—California’s worst in decades—led to a premature harvest of wine grapes this year.

The earthquake caused a number of Napa wineries to lose a substantial portion of the wine they held. Barrels collapsed and bottles smashed; some of the region’s top-of-the-line, premium wines were spilled out. Some experts estimated that the economic cost of the earthquake to Napa Valley could reach $100 million.

Additional World Book articles:

• Agriculture

• The Colorado River: Lifeline to the Southwest (A Special Report)

• Wine

June 19, 2014

Evidence of a vast reservoir of water long thought to exist deep within Earth has been revealed in two recent studies. The reservoir, which may contain as much water as all of Earth’s oceans, is more than 300 miles (480 kilometers) below the surface in the mantle, the enormously thick layer of rock between Earth’s crust and inner core. One line of evidence for the reservoir was reported this month by scientists who analyzed seismic waves passing through the mantle beneath the United States. Another line of evidence, reported earlier this year, came from a battered diamond found in Brazil.

Scientists were quick to explain that the reservoir does not look like an underground sea. Instead, the water is locked within tiny grains of a kind of mineral called ringwoodite that forms in the searing temperatures and crushing pressures of the mantle. The water is not even a liquid or a vapor. It consists of hydroxide ions, negatively charged atoms of hydrogen and oxygen bound together. One scientists described the reservoir as a layer of “mushy rock.”

Beneath Earth's solid crust are the mantle, the outer core, and the inner core. Scientists can learn about the inside of Earth by studying how waves from earthquakes travel through the planet. (World Book illustration by Raymond Perlman and Steven Brayfield, Artisan-Chicago)

The seismic evidence was collected by scientists analyzing data collected by the Transportable Array (TA), an ambitious earth science observatory funded by the National Academy of Sciences. The TA consists of hundreds of portable seismic stations that measure waves of energy passing through Earth’s layers during earthquakes or other seismic events. Arranged in a grid pattern, the stations were rolled eastward across North America over a 10-year period. The scientists found that the speed of the waves changed as they passed through a part of the mantle called the transition zone. This suggested that the ringwoodite in this zone was melting. Finding evidence of melting at such an unusual depth, the scientists concluded, indicated that the ringwoodite was releasing water as it was carried deeper into the mantle.

The other study involved an analysis of a diamond shot from the transition zone to the surface through a volcanic eruption called a kimberlite. The diamond, which scientists said, looked like it had been “to hell and back,” contained a sample of water-bearing ringwoodite. It is the only known piece of ringwoodite ever found naturally on Earth’s surface. All other samples of the mineral, which lies too deep to be obtained by drilling, have come from meteorites or have been produced in scientific laboratories.

Scientists said that in addition for providing evidence of Earth’s hidden ocean, the research may shed new light on the movement of the tectonic plates that make up Earth’s outer surface. The findings also bolster the theory that the water in Earth’s oceans and lakes came from rocks that formed early in Earth’s history, not from icy comets that bombarded the surface.

Additional Woirld Book articles:

• Water cycle

May 12, 2014

The Washington Monument in Washington, D.C., reopened today, after a nearly three-year effort to repair damage caused by an earthquake in August 2011. The 5.8-magnitude quake, whose epicenter lay about 85 miles (135 kilometers) southwest of the capital, had rumbled under much of the northeastern United States. The shaking loosened stones in the hollow monument, damaged an elevator, and caused some 150 cracks to appear on its outer surface. The cracks left the structure vulnerable to Hurricane Irene, which rolled over the Eastern Seaboard a few days after the earthquake. Water seeped in, especially at the monument’s pyramid top. Despite the damage, National Park Service officials said that the monument remained structurally sound.

A team of engineers inspects the Washington Monument for damage in September 2011. A month earlier, a 5.8-magnitude earthquake rattled Washington, D.C., and other parts of the northeastern United States. (AP Photo)

The 555-foot (169-meter) obelisk was built as a tribute to George Washington, the American colonists’ military leader during the American Revolution and the first president of the United States. Completed on Dec. 6, 1884, the monument was dedicated on Feb. 21, 1885. It opened to the public on Oct. 9, 1888. The construction was financed by public donations and some government funds. The recently completed $15-million repair project was funded equally by a donation from David Rubenstein, an American financier and philanthropist, and an appropriation by Congress. The monument is among the most popular attractions in Washington, D.C. Added during the repair project were new exhibits on the top floor.

Additional World Book articles:

• Martha Custis Washington
• Mount Vernon
• First in War, First in Peace… But Not in Libraries (a Special Report)

April 2, 2014

A magnitude-8.2 earthquake slammed northern Chile last night, setting off a tsunami that forced tens of thousands of people to evacuate the country’s 2,650-mile- (4,260-kilometer-) long coastline. Waves as high as 6 feet (2.1 meters) were reported in some areas as well as along the Peruvian coast. The coasts of Peru, Ecuador, Colombia, Panama, Costa Rica, and Nicaragua were put on alert, and an advisory was issued for Hawaii. However, no major damage was reported. Electric power failed across much of Arica, a port city of about 200,000 people. The death toll across the region remains uncertain.

The quake was felt as far away as Bolivia’s capital, La Paz, some 300 miles (480 kilometers) from the earthquake’s epicenter off the coast near the Chilean copper mining city of Iquique, which is also a major port. During an evacuation in that city, some 300 prisoners escaped from a woman’s prison.

An earthquake occurs when Earth’s rock suddenly breaks and shifts, releasing energy in vibrations called seismic waves. The point on Earth where the rock first breaks is called the focus. The point on the surface above is known as the epicenter. (World Book illustration)

A tsunami can occur when an underwater earthquake displaces a large part of the sea floor. In this illustration, a tsunami wave spreads from a fast-rising section of ocean floor. The rising plate lifts the water above it, raising a hump of water that quickly ripples outward. As the ripple enters shallow water, it slows and grows in height. (World Book illustration by Matt Carrington)

Chile lies in one of the world’s most earthquake-prone zones. In 2010, a magnitude-8.8 earthquake off the coast of central Chile left more than 500 people dead. In 1960, a magnitude-9.5 earthquake hit off Chile’s coast near the city of Valdivia. More than 1,600 people were killed, largely from a subsequent tsunami. Seismologists believe the 1960 quake was the largest of the 20th century.

Additional World Book articles:

• Plate tectonics
• Big Waves: Tracking Deadly Tsunamis (a special report)
• When the Earth Moves (a special report)
• Chile 1960 (a Back in Time article)
• Chile 2010 (a Back in Time article)