Natural Hazards

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Natural Hazards
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Natural Hazards

• Different types of Natural Hazards

Volcanoes
Forest Fires
Tsunamis
Avalanches
Earthquakes
Lightning
Hurricanes, Cyclones, Typhoons
Landslides
Floods
Tornadoes
Extreme Temperatures
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Geohazards

• A natural event on the Earth that causes loss of
  life or property

Geo-Process
HumanProcess
HazardousResult
Courtesy of Swisseduc.ch
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Human Process

• Earths population increasing
• More people will live in hazard areas

2008 6 billion people 2025 8 billion people
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Types of Natural Hazards
Mt. St. Helens

• Precursors are warnings

Japan
Photo by D. Frank, March 27, 1980
Cyclone Tracy, Australia
Mt. St. Helens
Photo by Harry Glicken, May 17, 1980
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Examples of Natural Hazards

• 3 geohazards which recently affected a lot of
  people

Tsunamis
Cyclones
Earthquakes
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Earthquakes

• What are earthquakes?
• Richter Scale
• San Francisco earthquake

Photo by J.K. Nagata
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What is an earthquake?

• The focus and epicentre

Izmit, Turkey
Photo by T. Fumal
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Earthquake Epicentre

• Body and Surface Waves

USGS Check cc
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Earthquake Magnitude

• Richter Scale

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Where do earthquakes happen?

• Earthquake locations on world map

Atlantic Ocean
Pacific Ocean
Strike-slip
Normal
Thrust
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San Francisco Earthquake, 1906

• The Great Earthquake
• Magnitude 7.7 to 8.3

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Loma Prieta Earthquake, 1989

• Quake of 89
• San Francisco Bay area
• Magnitude 6.9 to 7.1

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Largest and Deadliest Earthquakes
Largest Earthquakes
Deadliest Earthquakes
4. 9.2
3. 9.3
5. 9.0
D. 230,000
B. 255,000
A. 830,000
E. 200,000
2. 9.3
C. 230,210
1. 9.5
Source USGS

• World map of top 5 largest and deadliest
  earthquakes

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Tsunami

• What are tsunamis?
• Boxing Day tsunami

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What is a tsunami?

• Tsunami means harbour wave

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2004 Boxing Day Tsunami

• Epicentre near Sumatra
• Earthquake magnitude 9.3
• Thrust fault

Epicentre
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2004 Boxing Day Tsunami

• Ao Nang, Thailand

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2004 Boxing Day Tsunami

• Village in Sumatra

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2004 Boxing Day Tsunami

• Phuket, Thailand

After
Before
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Tropical Storms

• Cylclones, Hurricanes and Typhoons

NASA
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What are tropical storms?

• Cyclones, Hurricanes, Typhoons

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How do cyclones form?

• Strong winds (63 km/h) Tropical Storm
• Stronger winds (gt119 km/h) Tropical Cyclone

Warm water
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Cyclone Damage

• Wind
• Flying debris
• Tree loss

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Cyclone Damage

• Storm Surge
• Water pushed toward shore by cyclone winds

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Cyclone Categories

• Saffir-Simpson Hurricane Scale

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Largest and Smallest Tropical Storms

• Typhoon Tip and Cyclone Tracy

Typhoon Tip
Cyclone Tracy
cc. Bidgee
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Cyclone Gorky

• Bangladesh 1991
• 138,000 dead

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Hurricane Katrina

• USA, 2005

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Hurricane Katrina

• Damage

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Question
?

• What can we do to help people who live in hazard
  areas?

1. Look and Learn
2. Watch/Early Warnings

• How often?
• How powerful?
• How big an area?

4. Infrastructure
3. Escape Plans
5. Teach
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Earthquake Mitigation

• Make buildings stronger
• Education
• Disaster plan

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Tsunami Mitigation

• Education
• Warning systems
• Evacuation plans

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Tsunami Mitigation

• Infrastructure

Hilo Harbour, Hawaii
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Tsunami Mitigation

• Infrastructure
• Seawalls

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Cyclone Mitigation

• Infrastructure
• Cyclone walls
• Shelters

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Brain Challenge

• Questions about Natural Hazards

1. Natural hazards are natural events that
happen on Mars Earth.
Landslide
2. Circle the geo-hazards a) tornado b)
building a house near a volcano c) landslide
d) earthquake
3. A fault is a large crack worm in the
Earth.
4. Which earthquake is stronger a magnitude
3 or 8 ?
5. Tsunami is a Japanese word for harbour
wave front.
6. An earthquake that happens under the stars
ocean could cause a tsunami.
7. Tropical storms are storms that spin
dance and have calm centres.
8. The equator is an imaginary friend line
which runs along the middle of the Earth,
dividing it in half.
9. Cyclones form over warm forest fires
ocean water.
10. A storm surge is caused by strong winds
hands pushing on the oceans surface.
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Activity
World total loss of life by disaster type 1947 -
1980
450048
180
Loss Of Life
Number Of Events
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The End
Typhoon Tip