Download Natural Hazards Notes

Natural Hazards Notes
What are they?
Where do they happen?
What kind of damage happens?
How have people adapted?
Earthquakes
• An earthquake is the result of a
sudden release of stored energy in
the Earth's crust along a fault line.
Earthquakes originate directly above the
focus point which is called the epicenter.
Damage
• Damage can be minor to major.
Adaptation/Modification
• Humans can build structures that
sway, expand, or contract to absorb
the shaking of the earth.
Volcanoes
• What is a volcano?
•
When pressure from the
molten rock beneath the
earth's surface becomes too
great, the rock, usually
accompanied by lava or
gases, escapes through a
fissure or vent in the crust of
the earth.
"Volcano" is the term given
to both the vent and the
conical mountain left by the
overflow of the erupted lava,
rock and ash.
Volcanoes happen along seduction
plate boundaries or where the
Earth’s crust is thin.
Damage
•
Adaptation/Modification
• People may live in
volcanic areas, but
no modifications to
the environment
can be made to
protect them from
their destructive
force.
Hurricanes
• When the winds in a tropical storm reach 75mph,
the storm is called a hurricane.
Where do they Occur?
• They happen over warm ocean waters in the low
latitude regions around the world.
• They are called: “hurricane” in the Atlantic Ocean,
“typhoon” in the Pacific Ocean, and “cyclone” in
the Indian Ocean
Damage
Winds determine the intensity of a hurricane
• Strong winds are the most
common means of destruction
associated with hurricanes. They
uproot trees, knock over buildings
and homes, fling potentially
deadly debris around, sink or
ground boats, and flip cars.
• Still, flooding kills more people
than the strong winds do.
Damage, Storm Surge
• One major cause of hurricane damage is storm
surge. Storm surge is the rising of the sea level
due to the low pressure, high winds, and high
waves associated with a hurricane as it makes
landfall. The storm surge can cause significant
flooding and cost people their lives if they're
caught unexpected.
Adapting for Hurricanes
• Homes and building are constructed with
extra supports systems to handle high
winds, but even these methods will not
prevent damage from storm surge or
winds that are extreme.
Tsunamis
• What causes a tsunami?... A tsunami is a
large ocean wave that is caused by sudden
motion on the ocean floor. This sudden
motion could be an earthquake, a powerful
volcanic eruption, or an underwater
landslide.
• Tsunamis travel across the open ocean at
great speeds and build into large deadly
waves in the shallow water of a shoreline.
Tsunamis can happen in any
ocean, but tend to originate at
plate boundaries
Earthquakes and Tsunamis
Tsunami Damage
Adapting to Tsunami’s
• One way people adapt to Tsunami’s is to
•
have early warning devices that will alert
others that a tsunami is on its way.
Plans call for the U.S. Tsunami warning
network to total 39 DART™ II buoy
stations by mid-summer 2008 (32 in the
Pacific and seven in the Atlantic Basin).
Flooding
• When an area receives more rainfall then
it can handle flooding occurs. This can
happen almost anywhere in the world.
Damage From Flooding
• Physical damage- Structures such as buildings get
damaged due to flood water. Landslides can also take
place.
• Casualties- People and livestock die due to drowning. It
can also lead to epidemics and diseases.
• Water supplies- Contamination of water. Clean
drinking water becomes scarce.
• Crops and food supplies- Shortage of food crops can
be caused due to loss of entire harvest
• Floods account for more than $1 billion in
property losses in the United States each year.
Adapting
• Flood planning and mitigation is based on
•
gathering high-quality information related
to a variety of physical, environmental, and
human conditions.
Flooding causes more damage in the United
States than any other severe weather related
event, an average of $4.6 billion a year in the
past 20 years (1984-2003). Flooding can occur
in any of the 50 states or U.S. territories at
anytime of the year.
Droughts
• Drought is a natural phenomenon, like
hurricanes, tornadoes, or earthquakes.
Unlike 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.
Where can Droughts happen
• Anywhere that climate change effects the
normal amount of precipitation over a period of
time.
Damage from Droughts
• Droughts causes between $6 billion and $8
billion a year in direct estimated losses to the
U.S. economy.
Adapting to Droughts
• Drought planning and mitigation is based on
gathering high-quality information related to a
variety of physical, environmental, and human
conditions.
• Notice
that
Texas one
of the top
five
States
that has
had major
weather
related
damage
Having a
family
emergency
plan can
save lives