Natural Hazards NotesNatural Hazards Notes

What are they?What are they?

Where do they happen?Where do they happen?

What kind of damage happens?What kind of damage happens?

How have people adapted?How have people adapted?

Earthquakes Earthquakes • An earthquake is the result of a An earthquake is the result of a

sudden release of stored energy sudden release of stored energy in the Earth's crust along a fault in the Earth's crust along a fault line.line.

Earthquakes originate directly above Earthquakes originate directly above the focus point which is called the the focus point which is called the epicenter.epicenter.

DamageDamage

• Damage can be minor to major.Damage can be minor to major.

Adaptation/ModificationAdaptation/Modification

• Humans can build structures Humans can build structures that sway, expand, or contract to that sway, expand, or contract to absorb the shaking of the earth.absorb the shaking of the earth.

Volcanoes Volcanoes

• What is a volcano?What is a volcano?When pressure from the molten When pressure from the molten rock beneath the earth's surface rock beneath the earth's surface becomes too great, the rock, becomes too great, the rock, usually accompanied by lava or usually accompanied by lava or gases, escapes through a gases, escapes through a fissure or vent in the crust of fissure or vent in the crust of the earth. the earth.

• "Volcano" is the term given to "Volcano" is the term given to both the vent and the conical both the vent and the conical mountain left by the overflow of mountain left by the overflow of the erupted lava, rock and ash.the erupted lava, rock and ash.

Volcanoes happen along Volcanoes happen along seduction plate boundaries or seduction plate boundaries or

where the Earth’s crust is thin.where the Earth’s crust is thin.

DamageDamage

•

Adaptation/ModificationAdaptation/Modification

• People may live in People may live in volcanic areas, but volcanic areas, but no modifications to no modifications to the environment the environment can be made to can be made to protect them from protect them from their destructive their destructive force. force.

HurricanesHurricanes

• When the winds in a tropical storm reach When the winds in a tropical storm reach 75mph, the storm is called a hurricane.75mph, the storm is called a hurricane.

Where do they Occur? Where do they Occur? • They happen over warm ocean waters in the They happen over warm ocean waters in the

low latitude regions around the world.low latitude regions around the world.• They are called: “They are called: “hurricanehurricane” in the Atlantic ” in the Atlantic

Ocean, “Ocean, “typhoontyphoon” in the Pacific Ocean, and ” in the Pacific Ocean, and ““cyclonecyclone” in the Indian Ocean” in the Indian Ocean

DamageDamageWindsWinds determine the intensity of a hurricane determine the intensity of a hurricane

• Strong winds are the most Strong winds are the most common means of destruction common means of destruction associated with hurricanes. associated with hurricanes. They uproot trees, knock over They uproot trees, knock over buildings and homes, fling buildings and homes, fling potentially deadly debris potentially deadly debris around, sink or ground boats, around, sink or ground boats, and flip cars. and flip cars.

• Still, flooding kills more people Still, flooding kills more people than the strong winds do.than the strong winds do.

Damage, Storm SurgeDamage, Storm Surge• One major cause of hurricane damage is One major cause of hurricane damage is

storm surge. Storm surge is the rising of the storm surge. Storm surge is the rising of the sea level due to the low pressure, high winds, sea level due to the low pressure, high winds, and high waves associated with a hurricane and high waves associated with a hurricane as it makes landfall. The storm surge can as it makes landfall. The storm surge can cause significant flooding and cost people cause significant flooding and cost people their lives if they're caught unexpected.their lives if they're caught unexpected.

Adapting for Hurricanes Adapting for Hurricanes • Homes and building are constructed Homes and building are constructed

with extra supports systems to with extra supports systems to handle high winds, but even these handle high winds, but even these methods will not prevent damage methods will not prevent damage from storm surge or winds that are from storm surge or winds that are extreme.extreme.

                           

TsunamisTsunamis

• What causes a tsunami?... A tsunami is a large ocean What causes a tsunami?... A tsunami is a large ocean wave that is caused by sudden motion on the ocean wave that is caused by sudden motion on the ocean floor. This sudden motion could be an earthquake, a floor. This sudden motion could be an earthquake, a powerful volcanic eruption, or an underwater powerful volcanic eruption, or an underwater landslide. landslide.

• Tsunamis travel across the open ocean at great Tsunamis travel across the open ocean at great speeds and build into large deadly waves in the speeds and build into large deadly waves in the shallow water of a shoreline.shallow water of a shoreline.

Tsunamis can happen in any Tsunamis can happen in any ocean, but tend to originate ocean, but tend to originate

at plate boundariesat plate boundaries

Earthquakes and Earthquakes and Tsunamis Tsunamis

Tsunami DamageTsunami Damage

Adapting to Tsunami’sAdapting to Tsunami’s• One way people adapt to Tsunami’s is to have early warning One way people adapt to Tsunami’s is to have early warning

devices that will alert others that a tsunami is on its way.devices that will alert others that a tsunami is on its way.• Plans call for the U.S. Tsunami warning network to total 39 Plans call for the U.S. Tsunami warning network to total 39

DART™ II buoy stations by mid-summer 2008 (32 in the DART™ II buoy stations by mid-summer 2008 (32 in the Pacific and seven in the Atlantic Basin).Pacific and seven in the Atlantic Basin).

FloodingFlooding•When an area receives more rainfall then

it can handle flooding occurs. This can happen almost anywhere in the world.

Damage From FloodingDamage From Flooding• Physical damagePhysical damage- Structures such as buildings get - Structures such as buildings get

damaged due to flood water. Landslides can also take damaged due to flood water. Landslides can also take place.place.

• CasualtiesCasualties- People and livestock die due to drowning. It - People and livestock die due to drowning. It can also lead to epidemics and diseases.can also lead to epidemics and diseases.

• Water suppliesWater supplies- Contamination of water. Clean drinking - Contamination of water. Clean drinking water becomes scarce.water becomes scarce.

• Crops and food suppliesCrops and food supplies- Shortage of food crops can be - Shortage of food crops can be caused due to loss of entire harvestcaused due to loss of entire harvest

• Floods account for more than $1 billion in property losses in Floods account for more than $1 billion in property losses in the United States each year.the United States each year.

AdaptingAdapting • Flood planning and mitigation is based Flood planning and mitigation is based

on gathering high-quality information on gathering high-quality information related to a variety of physical, related to a variety of physical, environmental, and human conditions.environmental, and human conditions.

• Flooding causes more damage in the United Flooding causes more damage in the United States than any other severe weather related States than any other severe weather related event, an average of $4.6 billion a year in the event, an average of $4.6 billion a year in the past 20 years (1984-2003). Flooding can occur past 20 years (1984-2003). Flooding can occur in any of the 50 states or U.S. territories at in any of the 50 states or U.S. territories at anytime of the year.anytime of the year.

DroughtsDroughts• Drought is a natural phenomenon, like hurricanes, tornadoes, or earthquakes. Unlike Drought is a natural phenomenon, like hurricanes, tornadoes, or earthquakes. Unlike

these examples, however, drought develops slowly, lasts longer, and often is very these examples, however, drought develops slowly, lasts longer, and often is very subtle – it can creep up on a region and cause damage before being identified. subtle – it can creep up on a region and cause damage before being identified.

Where can Droughts happenWhere can Droughts happen• Anywhere that climate change effects the normal amount of precipitation over a period of time.Anywhere that climate change effects the normal amount of precipitation over a period of time.

Damage from DroughtsDamage from Droughts• Droughts causes between $6 billion and $8 billion a year in direct estimated losses to the U.S. Droughts causes between $6 billion and $8 billion a year in direct estimated losses to the U.S.

economy.economy.

Adapting to DroughtsAdapting to Droughts • Drought planning and mitigation is based on gathering high-quality information related to a variety Drought planning and mitigation is based on gathering high-quality information related to a variety

of physical, environmental, and human conditions.of physical, environmental, and human conditions.

• Notice Notice that that Texas one Texas one of the top of the top five five States States that has that has had major had major weather weather related related damagedamage

Having a Having a family family emergencemergency plan can y plan can save livessave lives