Natural Hazards, miltigation and adaptation. Powerpoint Presentation for students

1. NATURAL HAZARDS,
MITIGATION,
ADAPTATION

2. INTRODUCTION
NATURAL HAZARDS
Events that occur as a part of the natural cycles
of Earth and may cause damage to a community.
The disruption of the normal functioning of a
community is called disaster.
VUNERABILITY
Defines by the United Nations Office of Disaster
Risk Reduction-
It refers to the “characteristic and circumstances
of a community, system, or asset that make of it
susceptible to the damaging effects of a hazard.”

3. HAZARDS CAUSED BY GEOLOGIC
PROCESSEARTHQUAKES
a. Ground Shaking
Ground shaking or ground motion, a principal cause of the
partial or total collapse of structures, is the vibration of the
ground caused by seismic waves during an earthquake.
b. Surface Faulting
Surface faulting is the offset or tearing of the ground surface
by differential movement along a fault during an earthquake.
C. Tsunamis
Very high, large waves or seismic sea waves caused by the
sudden movement of the ocean floor.

4. HAZARDS CAUSED BY GEOLOGIC
PROCESS VOLCANIC ERUPTIONS
a. Lahars and Floods
A lahar (or mudflow) is a flowing slurry of volcanic debris and
water that originates on a volcano. The eruption of a snow-
covered volcano can melt enough snow to cause a lahar.
b. Lava Flows and Domes
Fluid lava forms long thin flows on slopes and flat-topped lava
lakes in flat areas and topographic depressions, while
viscous lava forms short stubby flows on slopes and steep-
sided domes around their vents. In either case lava flows
seldom threaten human life because they move slowly and
their path can be predicted.
Volcanic Eruption may only be predicted a week or days
before occurrence. Despite Philippines being part of the Ring
of Fire.

5. HAZARDS CAUSED BY GEOLOGIC
PROCESSLANDSLIDES
Occur in a sloping terrain. It can be triggered by
rainfall or earthquake.
1. Rainfall-induced- caused by heavy rains
that can loosen soil and makes the
foundations of the structures weak.
2. Earthquake-induced- occurs during or after
an earthquake due to gravity.
Earthquakes may either be a natural occurance
or man-made.

6. PREVENTION MANAGEMENT of GEOLOGICAL
HAZARDS

7. PREVENTION MANAGEMENT of GEOLOGICAL
HAZARDS
What to Do Before an Earthquake
Make sure you have a fire extinguisher, first
aid kit, a battery-powered radio, a
flashlight, and extra batteries at home.
Learn first aid.
Learn how to turn off the gas, water, and
electricity.
Make up a plan of where to meet your family
after an earthquake.
Don't leave heavy objects on shelves (they'll
fall during a quake).
What to Do During an Earthquake
Stay calm! If you're indoors, stay inside. If you're
outside, stay outside.
If you're indoors, stand against a wall near the center of
the building, stand in a doorway, or crawl under
heavy furniture (a desk or table). Stay away from
windows and outside doors.
If you're outdoors, stay in the open away from power
lines or anything that might fall. Stay away from
buildings (stuff might fall off the building or the
building could fall on you).
Don't use matches, candles, or any flame. Broken gas
lines and fire don't mix.
If you're in a car, stop the car and stay inside the car

8. PREVENTION MANAGEMENT of GEOLOGICAL
HAZARDS
What to Do After an Earthquake
Check yourself and others for injuries. Provide first
aid for anyone who needs it.
Check water, gas, and electric lines for damage. If
any are damaged, shut off the valves. Check
for the smell of gas. If you smell it, open all
the windows and doors, leave immediately,
and report it to the authorities (use someone
else's phone).
Turn on the radio. Don't use the phone unless it's an
emergency.
Stay out of damaged buildings.
Be careful of chimneys (they may fall on you).
Stay away from beaches. Tsunamis and seiches
sometimes hit after the ground has stopped
shaking.
Stay away from damaged areas.
If you're at school or work, follow the emergency
plan or the instructions of the person in
charge.
Expect aftershocks.

9. PREVENTION MANAGEMENT of GEOLOGICAL
HAZARDS
MANAGING VOLCANIC ERUPTIONS
1. Take note of surroundings.
2. Gather all members of household.
3. Put together an emergency supply kit.
4. Put important things on containers etc.
preventing from ashfall.
5. Follow instruction of local authorities.
Volcanic activities is being watched by the-
Philippine Institute of Volcanology and Seismology or
PHILVOCS

10. PREVENTION MANAGEMENT of GEOLOGICAL
HAZARDS
MANAGING LANDSLIDES
1. Plant more trees.
2. Build channels for diversion of
mudflow
3. Put together an emergency
supply kit.
4. Put important things on
containers etc. preventing from
ashfall.
If landslides occur without warning:
1. Stay alert
2. Be attentive
3. Stay away from lower elevations
or paths of debris
4. Take shelter under sturdy table
or structure.

11. Hazards caused by
Hydrometeorologica
l Phenomena
FACTS:
Intertropical Convergence Zone
-the area that encircles the Earth near the
equator where trade winds meet.
The Philippines is in the Northern
Hemisphere, near the equator.
PAGASA or Philippine Atmospheric,
Geophysical and Astronomical Services and
Administration- the govern ment agency that
provides information on meteorological,
astronomical and climatological activities in
the Philippine territory.
Common Hydrometeorological Phenomenon
1. Tropical Cyclones-
Typhoons (Northwest Pacific) or hurricanes (Atlantic and
Northeast region) are storm system characterized by rapid
spiraling storms, low-pressure center, and intensely strong winds.
Cyclones can increase the Strength of winds, which may cause
tropical depression (45-62 km/h), storm (63-117 km/h), a typhonn
(118-239 km/h), and a super typhoon (240 km/h or higher).

12. Hazards caused by Hydrometeorological
Phenomena
2. Monsoons
These are seasonal winds. The Philippines
expect two monsoons every year:
Amihan - or northeast monsoon is
characterized by cold gusty winds with little
precipitation. It begins in early Sptember -
May or June. Winds vlow in the east.
Habagat- or southwest monsoon is
characterized by hot and humid atmosphere
with fequent or heavy rainfall. It begins in
June snd Ends in August or September.
Winds blow in the west

13. 3. Tornado
Locally known as ipo-ipo. It is a rapidly swirling
condensation funnel whose narrow end comes in contact
with the ground. It usually carries debris and other objects
that can be picked up from the ground.
Tornadoes occur anywhere in an average number of 12-24
times a year.
Characterized by:
Storm
Debris
Fire
Hazards caused by Hydrometeorological
Phenomena

14. Common
Coastal Hazard COMMON COASTAL HAZARDS:
Coastal Erosion
Submersion
Storm Surges
Saltwater Intrusion
Coastal areas are transition places
between land and sea. These areas
are considered low-lying. It is very
dynamic, It interacts with all
natural systems and proocesses
that happened on land, in the
marine environment and in the
atmosphere.

15. Submersion
-s the sustainable cyclic portion of coastal erosion
where coastal sediments move from the visible
portion of a beach to the submerged near shore
region, and later return to the original visible portion of
the beach. The recovery portion of the sustainable
cycle of sediment behaviour is (accretion).
Coastal Erosion
-is the wearing away of land and the removal of
beach or dune sediments by wave action, tidal
currents, wave currents, drainage or high winds
(see also beach evolution).

16. Saltwater Intrusion
-Saltwater intrusion is the movement of saline water
into freshwater aquifers, which can lead to
contamination of drinking water sources and other
consequences. Saltwater intrusion occurs naturally to
some degree in most coastal aquifers, owing to the
hydraulic connection between groundwater and
seawater.
Storm Surges
-is a rise in sea level that occurs during tropical
cyclones, intensestorms also known as typhoons or
hurricanes. The storms produce strong winds that push
the water into shore, which can lead to flooding. This
makes storm surges very dangerous for coastal
regions.

17. Coastal Hazard-prone areas in the PH
Local government units in areas that are ranked
extremely high in susceptibility to landslide and
flooding are advised to immediately relocate the
residents of these zones to safer areas. Especially
typhoons that can cause coastal hazards.
The figure shows the areas prone to coastal
hazard.

18. Prevention and Management of Marine and Coastal Hazards
1. Prepare and emergency survival
kit.
2. Create an evacuation plan.
3. Know where the evacuation
center is and how to get there.
4. Listen to news from any means.