Hazards

Natural Hazards, Mitigation, and

Adaptation

LEARNING TARGETS

LEARNING TARGETS

LEARNING TARGETS

CANVAS LEARNING MATERIALS

CANVAS LEARNING MATERIALS

Poll

How are you feeling right now?

• I can focus!

• I'm fine...

• I can't focus right now 🥲

Open Ended

Lights, Camera, Action!

What disaster-themed movie or TV series scared or impacted you the most? Why?

It is a weak or
violent shaking of
the ground
produced by the
sudden movement
of rock materials
below the earth’s
surface.

EARTHQUAKE

Earthquake is
measured through:

1. Magnitude
2. Intensity

EARTHQUAKE

Earthquake Hazards
lifted off a flyer from
PHIVOLCS:

EARTHQUAKE HAZARDS

Earthquake
Hazards lifted
off a flyer from
PHIVOLCS:

EARTHQUAKE HAZARDS

EARTHQUAKE HAZARDS

​Tsunami Video

EARTHQUAKE HAZARDS

Earthquake
Hazards lifted off
a flyer from
PHIVOLCS:

Earthquake
Hazards lifted off
a flyer from
PHIVOLCS:

EARTHQUAKE HAZARDS

EARTHQUAKE HAZARDS

​Liquefaction video

Earthquake
Hazards lifted
off a flyer from
PHIVOLCS:

EARTHQUAKE HAZARDS

The largest recorded
earthquake in modern history occurred on May 22, 1960, in Chile. The earthquake triggered
a powerful tsunami that
traveled across the Pacific
Ocean, causing devastation as far away as Japan, New
Zealand, and the Philippines.

What a FACT!

Open Ended

What is your most vivid memory of an earthquake? How did you react to the situation?

EARTHQUAKE

Earthquake Hazards

Definition

1.Ground Rupture

Deformation of the ground that marks the
intersection of the fault with earth’s surface.

2. Tsunami

Series of waves caused commonly by an
earthquake under the sea.

3. Ground Shaking

Disruptive up, down, and sideways vibration
of the ground.

4. Liquefaction

Sediments behave like a liquid due to
emergence of groundwater.

5. Earthquake-Induced Landslide

Downslope movement of rocks, soil, and
other debris commonly triggered

Open Ended

What is your family's emergency plan before, during, and after an earthquake?

Vent, hill, or
mountain from
which molten or hot
rocks with gaseous
material have been
ejected.

Volcano

Volcanic Hazards

Volcanic hazards directly associated with an

eruption

Volcanic hazards indirectly associated with an

eruption

1.Lava Flow

1.Lahar, flooding

2. Tephra fall or ashfall and ballistic
projectiles

2. Debris avalanche, landslide

3. Pyroclastic density currents or PDCs
(pyroclastic flow, pyroclastic surge, base
surge)

3. Volcanic tsunami

4. Lateral blast

4. Ground deformation (subsidence,
fissuring)

5. Volcanic gas

5. Secondary explosion

Volcanic hazards directly associated with an eruption

Definitions

1.Lava Flow

These are rivers of incandescent molten rock or lava moving
downslope or away from an eruption vent.

2. Tephra fall or ashfall and ballistic
projectiles

These are propelled through the atmosphere in an eruption
plume or an eruption column eventually fall or gravitationally
settle over areas downwind of an erupting volcano, forming
blankets of tephra fall or ashfall.

3. Pyroclastic density currents or PDCs
(pyroclastic flow, pyroclastic surge, base surge)

Theseare mixtures of fragmented volcanic particles
(pyroclastics), hot gases, and ash that rush down the
volcanic slopes or rapidly outward from a source vent at
high speeds.

4. Lateral blast

These are laterally-directed thrusts of hot gas and ash that
can be generated from an exploding dome on the summit
vent or inside the edifice when sudden mass failure of the
volcanic flanks occurs.

5. Volcanic gas

These form a dissolved component of magma that is
released into the atmosphere in large quantities during
eruptions.

Open Ended

What is the most dangerous among the mentioned volcanic hazards? Why?

Reference:
https://volcanoes.usgs.gov/Imgs/Jpg/Mayon/32923351-020_caption.html

A landslide is a mass
movement of rock, soil, and debris down a slope due to gravity. It occurs when the driving force is
greater than the resisting force

LANDSLIDE

Image source:
https://www.nbcnews.com/news/world/typhoon-hit-philippin
es-rescuers-use-bare-hands-look-survivors-massive-n910111

●Natural triggers such as earthquakes
and mass wasting due to steep
slopes, weakening of slope material,
weathering of rocks, and overloading
on the slope

●Intense rainfall

●Weathering of rocks

●Ground vibrations created during
earthquakes

●Volcanic activity

●Man-made triggers such as mining
activities, construction of villages, and
high rise buildings

What triggers landslides to occur?

Landslides

A girl trapped in a landslide

Open Ended

Has your family (or you) ever been drastically affected by a typhoon? What was your experience? What actions did you take afterward?

TROPICAL
CYCLONES-
Hazard Map

Effects of a Tropical Cyclone

Strong winds

A squall is defined as an event in which the surface wind increases in
magnitude above the mean by factors of 1.2 to 1.6 or higher and is
maintained over a time interval of several minutes to one-half hour.

Tornadoes

These are tropical cyclones spawned which are expected for about half of
the storms of tropical storm intensity.

Rainfall and
flooding

Rainfall associated with tropical cyclones is both beneficial and harmful.
Although the rains contribute to the water needs of the areas traversed by
the cyclones, the rains are harmful when the amount is so large as to cause
flooding.

Storm surge

This is an abnormal rise of water due to a tropical cyclone and it is an
oceanic event responding to meteorological driving forces.

TROPICAL CYCLONES

Let's Check your Understanding!

Multiple Choice

Which of the following associated with tropical cyclones is both beneficial and harmful?

• Rainfall and flooding

• Tornado

• Storm surge

• Strong winds

Multiple Choice

Which typhoon signal no. has a minimal to minor threat to people and properties?

• Storm signal no. 1

• Storm signal no. 2

• Storm signal no. 3

• Storm signal no. 4

Multiple Choice

Which refers to an
oceanic event responding to meteorological driving forces?

• Rainfall and flooding

• Tornado

• Strong winds

• Storm surge

Multiple Choice

Which typhoon signal no. refers to moderate to significant threat to life and property?

• Storm signal no. 1

• Storm signal no. 2

• Storm signal no. 3

• Storm signal no. 4

Multiple Choice

Refer to the photo. Which regions in the Philippines is usually hit by Storm signal no. 5?

• Region V and Region IX

• Region II and Region VIII

• Region III and Region XI

• Region IV and Region VI

Open Ended

Wishful Thinking:

If you would be given a "superpower" to "eliminate" one of these four phenomena (earthquake, volcanic eruption, landslide, tropical cyclones), which one would you want to get rid of? Why?

What are the primary natural factors contributing to shoreline

changes in the Philippines, and how do they interact with

human activities to shape the coastal landscape?

MARINE AND COASTAL PROCESSES
AND THEIR EFFECTS

MARINE AND COASTAL PROCESSES AND
THEIR EFFECTS

Waves, currents,
and tides

They can influence the coastal areas in many ways and are the primary causes of
coastal abrasion/erosion and to some extent, coastal accretion. Stronger wave
energy equates to a higher rate of erosion and/or accretion.

Geology of a
coastline

A vital factor in shoreline change including the coast’s rock assemblage and its
tectonic imprints.

Climate

Monsoons and cold fronts may increase precipitations which can propagate high
and stronger waves. Moreover, the relative sea-level rise causes shoreline retreat
and may aggravate coastal erosion.

Anthropogenic
factors

These coastal alterations alter natural processes since some will interrupt littoral
drift and impoundment of sand at the expense of the beach downdrift of the
structures.

The isolated rock stock outcropping
along the beach of Bgy. Omawas,

Maydolong, Samar were originally part
of the promontory (black dashed lines

suggest the original outline of the
promontory). Due to the actions of
waves, erosion, and weathering, it

became a sea cave and then a sea ark
(as shown by the arrow), and eventually

a sea stack.

MARINE AND COASTAL PROCESSES
AND THEIR EFFECTS

The photo beside shows a

sea stack photographed at El
Nido, Palawan. A sea stack is
a coastal erosional landform
formed by wave action and is
typically exemplified by steep

and vertical columns.

MARINE AND COASTAL PROCESSES
AND THEIR EFFECTS

Headland (encircled) is
made up of harder rocks,
hence the last to erode

while the bay is composed
of softer rocks and the first

to erode.

MARINE AND COASTAL PROCESSES
AND THEIR EFFECTS

Another prominent
limestone block with

contorted bedding that

served as wave dissipator
in Caramoan, Camarines

Sur.

MARINE AND COASTAL PROCESSES
AND THEIR EFFECTS

Coastal submergence contributes to
land loss in several ways. The most

easily recognized effects of

submergence are land losses

caused by permanent flooding. The

passive inundation of the shore

typically expands estuaries, lakes,

and lagoons at the expense of
adjacent uplands and wetlands.

Submergence and Salt Intrusions

Saltwater intrusion is the

movement of seawater into
freshwater aquifers due to
natural processes or human

activities. Seawater intrusion is

caused by decreases in

groundwater levels or by rises in

seawater levels.

Submergence and Salt Intrusions

Let's Check your Understanding!

Multiple Choice

What is the term for the scale used to measure the magnitude of an earthquake?

• Intensity Scale

• Richter Scale

• Storm Scale

• Cyclone Scale

Multiple Choice

The term "storm surge" is most closely associated with:

• Earthquakes

• Typhoons

• Saltwater intrusion

• Tornadoes

Multiple Choice

Which earthquake hazard pertains to sediments that behave like a liquid due to
the emergence of groundwater?

• Waves

• Ground rupture

• Tsunami

• Liquefaction

Multiple Choice

Which refers to the movement of saltwater to freshwater due to human activities?

• Freshwater intrusion

• Saltwater intrusion

• Lake intrusion

• Ocean intrusion

Multiple Choice

Which of the following triggers of a landslide DOES NOT BELONG to the group?

• Earthquake

• Volcanic eruption

• Weathering of rocks

• Saltwater intrusion

Open Ended

As a Lasallian Leader, how would you take care of the environment and how would you promote it to the other people?

Poll

The topics under Module is:

• Sunny

• Cloudy

• Stormy

Natural Hazards, Mitigation, and

Adaptation