Volcanoes affect Earth’s land, air and water

GomaCongo, Africa2002

NyiragongonE-"ir-&-'go[ng]-(")gO

The Damage:• Lava cut off routes into Goma, dividing the city in two.• 40% of the town was destroyed.• Tens of thousands of people left homeless.• Tremors kept shaking the area, collapsing remaining structures.

Naples, ItalyPopulation: 1.7 million

"Mount Vesuvius is currently the most threatening volcano in the world, because of the dense population living in the area.” - Prof. Franco Barberi, Rome University

Danger: Pyroclastic Flows

Immediate Effects

• Lava flows• Ash• Mudflows• Pyroclastic flows• Landslides• Tsunamis• Steam Explosions

Lava flows

• Most flows move very slowly.

• Will knock down, cover, or burn nearly everything in their path.

Volcanic Ash• Heavy, made of

tiny pieces of volcanic rock.

• Causes roofs to collapse, makes roads slippery, clogs up machinery, suffocates plants and animals.

Mudflows• Loose rocks and

soil mixed with ice and snow from the top of the volcano.

• Rivers of ash.• Fast moving

mudflows have buried entire towns long distances away.

• Knocks down and burns everything in its path.

• Fast moving flows can sweep up and over hills then race back downhill.

• Saint Pierre, West Indies (1902): 30,000 people killed in minutes.

Pyroclastic flows

Landslides• Caused when

part of a volcano collapses.

• Rapid downhill movement of rock and soil.

• Large landslides into the sea may cause tsunamis.

Tsunamis

• Series of huge waves that are started by earthquakes and volcanoes.

• Can travel at speeds of 450mph and reach heights of 100 feet.

Steam explosions

• Uncommon, but can be devastating.

• Happens when lava hits water.

• May be responsible for the entire island of Krakatau exploding in 1883, causing tsunamis that killed over 36,000.

Long-term effects

• After eruptions volcanoes can remain dangerous for many years.

• Residual ash can combine with water to form mudflows in areas that receive heavy rains like the Philippines.

How dangerous?Rank the following in the order of most to

least dangerous.______ Lava Flows______ Mudflows______ Volcanic Ash______ Pyroclastic flows______ Landslides______ Tsunamis______ Steam Explosions

Be ready to

defend

your choice

s!