SCIENCE

The death toll from Guatemala’s Fuego volcano has risen to at least 99, with at least 192 missing. There have been no fatalities resulting from volcanic activity at Hawaii’s Kilauea. Why the disparity? (National Geographic)

Why is Fuego more deadly than Kilauea? Use our lesson to help support the video and article from Nat Geo.

Teachers, scroll down for a quick list of key resources in our Teachers Toolkit, including a link to today’s MapMaker Interactive map.

Discussion Ideas

• Guatemala experienced its deadliest volcanic event in more than 30 years when the Fuego volcano erupted. Where is Fuego?
  • Fuego is one of three large volcanoes overlooking Guatemala’s former capital, Antigua, only 43 kilometers (27 miles) from its current capital and largest urban area, Guatemala City. (Another one of those volcanoes, Pacaya, has started to spew lava.) More than 7 million people live within 100 kilometers (62 miles) of the volcano.
  • Fuego is one of Central America’s most active volcanoes, having erupted at least 79 times over the past 400 years and six times in 2017 alone. Learn more about Fuego from the good folks at the Global Volcanism Program here.
  • Fuego and the western coast of Central America are eastern extents of the “Ring of Fire”, a pattern of volcanic and seismic activity roughly ringing the Pacific Ocean.

• Take a look at today’s MapMaker Interactive map. What tectonic plates are influencing volcanic activity around Fuego and western Guatemala?
  • Seismic and volcanic activity are largely influenced by the interaction between the Cocos plate to the west and the Caribbean plate to the east. The subduction zone formed where the Cocos plate is subducting beneath the Caribbean and North American plates is called the Middle American trench.

• Read through the short Nat Geo article. Why has Fuego proven more deadly than Kilauea? A quick look at our reference resource might help—both Fuego and Kilauea are used as examples!
  • Fuego is a stratovolcano. Stratovolcanoes are some of the most easily recognizable and imposing volcanoes, with steep, conic peaks rising up to several thousand meters above the landscape. Also known as composite volcanoes, they are made up of layers of lava, volcanic ash, and fragmented rocks. These layers are built up over time as the volcano erupts through a vent or group of vents at the summit’s crater. Other stratovolcanoes include Vesuvius, Italy, and Krakatoa, Indonesia.
  • Kilauea is a shield volcano. Shield volcanoes are built almost exclusively of lava, which flows out in all directions during an eruption. These flows, made of highly fluid basalt lava, spread over great distances and cool in thin layers. Over time, the layers build up and create a gently sloping dome that looks like a warrior’s shield. While they are not as eye-catching as their steep stratovolcano cousins, shield volcanoes are often much larger in volume because of their broad, expansive structure.  All of the Hawaiian islands are made up of shield volcanoes.
  • “Whereas Kilauea, a shield volcano, is characterized by large globs of slow-moving lava inching out of fissures, Fuego, a stratovolcano, is prone to spewing fast-moving flows of ash, lava, and mud.
  • “‘The magma itself is quite different,’ says one expert. “The magma at Kilauea is quite runny, which means the gases can easily escape. At Fuego, the magma is stickier and more viscous.’
    • “That sticky magma traps enough air to build up pressure until an explosive eruption occurs.”

• Take a look at the “Volcanic Hazards” section of our reference resource. What volcanic hazards do you think are associated with the explosive eruption of Fuego?
  • pyroclastic flows. Probably the most dangerous of all volcanic hazards, a pyroclastic flow is a fast-moving torrent of volcanic ash, lava, and gas that flows from a volcano. Pyroclastic flows are responsible for almost all the deaths associated with Fuego and other stratovolcanoes.
  • lahars. “After these pyroclastic flows disperse, the loose rock stays behind. Because much of Guatemala is tropical, it experiences frequent and heavy rainfall. When this mixes with the volcanic debris, rainfall can form dangerous mudflows called lahars. With minimal rainfall, the lahars move like wet concrete, but after intense rains, they can turn into watery flash floods that inundate valleys.” Lahars are responsible for many of the most recent deaths at Fuego, as a fast-moving current suddenly changed direction and buried the town of El Rodeo before residents were done evacuating.
  • volcanic ash. Volcanic ash can reduce visibility, prevent air travel, damage infrastructure, and harm human health.
    • lowered visibility. Plumes of volcanic ash can spread over large areas of sky, turning daylight into complete darkness and drastically reducing visibility.
    • air travel. Airborne volcanic ash is especially dangerous to moving aircraft. The small, abrasive particles of rock and glass can melt inside an airplane engine and solidify on the turbine blades—causing the engine to stall. La Aurora International Airport, serving Guatemala City and the country’s largest airport, was closed for two days following the eruption.
    • destroyed infrastructure. Ash can enter and disrupt machinery found in power supply, water supply, sewage treatment, and communication facilities. Heavy ash fall can also inhibit road and rail traffic and damage vehicles. When mixed with rainfall, volcanic ash turns into a heavy, cement-like sludge can collapse roofs. This has already happened throughout communities impacted by the Fuego eruption.
      • reduced crop yield. Fuego’s last major eruption, in 1974, destroyed all vegetation surrounding the volcano. Crops were destroyed, making residents economically vulnerable, and loss of trees made the region more vulnerable to flooding during Guatemala’s frequent storms.
    • poor health. Carbon dioxide and fluorine, gases that can be toxic to humans, can collect in volcanic ash. The resulting ash fall can lead to animal death and deformity, as well as human illness. Ash’s abrasive particles can scratch the surface of the skin and eyes, causing discomfort and inflammation. If inhaled, volcanic ash can cause breathing problems and damage the lungs. Inhaling large amounts of ash and volcanic gases can cause a person to suffocate. Almost all emergency personnel at Fuego have been wearing thick masks to block the harmful ash.
  • volcanic gas. “In addition to ash, the plume contains gaseous components invisible to the human eye, including sulfur dioxide (SO2). The gas can affect human health—irritating the nose and throat when breathed in—and reacts with water vapor to produce acid rain.”
  • displacement. Fuego will continue to erupt, although not as explosively. Authorities fear thousands of Guatemalans will be internally displaced people—a population without homes, jobs, schools, businesses, hospitals, community centers, or neighborhoods.

TEACHERS TOOLKIT

Nat Geo: Why Guatemala’s Volcano Is Deadlier Than Hawaii’s

Nat Geo: Types of Volcanic Eruptions

Nat Geo: Where is Fuego?

Global Volcanism Program: Fuego

NASA Earth Observatory: A Deadly Eruption Rocks Guatemala

Nat Geo: What is a volcano?

Nat Geo: What is a pyroclastic flow?

Nat Geo: What is volcanic ash?