Cuenca Institute

JUNIOR High School Department

Gen. Malvar Street, Brgy 3, Cuenca, Batangas
2.3
Module No.
(043) 342-2045 | cuenca_institute@yahoo.com
SY 2020-2021 | First Semester

Name of Learner ___________________________________________

Strand & Section ___________________________________________

Understanding Typhoon

GRADE 8-SCIENCE
NESTORA C. MENDOZA
0929-252-8767

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Module 2.3 2nd Quarter
Learning Competency:
Explains how typhoon develops
Infer why the Philippines is prone to typhoon

INTRODUCTION

Every year the Philippines is hit by typhoons. No part of the

country is spared. All provinces have been visited by a typhoon
at one time or another. In recent years, the Philippines had been
overwhelmed by powerful tropical cyclones. Who could forget
the terrible flood brought by Tropical Storm Ondoy in 2009 or
the people swept out to sea during Tropical Storm Sendong in
2011or the poor community of New Bataan buried in mud
spawned by Typhoon Pablo in 2012? According to the Philip-
pine Atmospheric, Geophysical, and Astronomical Services Ad-
ministration (PAGASA), about 20 tropical cyclones enter the
Philippine Area of Responsibility each year. We have to be
knowledgeable about tropical cyclones if we want to prevent
the loss of more lives.
PRE TEST
Direction: For each item, encircle the letter of the correct answer.

1. Typhoons ______ power as they move over warm bodies of water.

a. lose b. equate
c. gain d. drop

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2. Where do typhoon forms?
a. in a river or stream b. under the earth
c. over the ocean d. at plate boundaries

3. All of the following will occur when wind blows over a warm ocean
water except
a. wind collects moisture b. warm air rises
c. pressure not affected d. cold air moves down

4. All of the following are conditions needed for a typhoon to form ex-
cept
a. a pre-existing disturbance b. warm ocean water
c. low atmospheric stability d. insufficient Coriolis force

5. Severe weather occurs, fiercest rains and most intense winds are
happening in what part of the typhoon?
a. Eye b. Inner Rain bands
c. Eye Wall d. Outer Rain Bands

6. When pressure is being created during the formation of typhoon,

winds do
a. move very quickly b. move slightly quick
c. move very slowly d. move slightly slow

7. The usual pattern of cold air movement is

a. risig up b. moving down
c.move horiontally d. move diagonally

8. Where are hurricanes/typhoons most likely do the most

damage?

a. in a desert b. in a forest
c. on the North pole d. near the seaboards

9. What part of a typhoon is known to us as “buntot ng bagyo?

a. Eye b. Rain bands
c. Eye Wall d. Rain tail

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10. All of the following are the same types of typhoons that differs
only in strength, location,speed and direction except one

a. Tropical Depression c. Typhoon & Hurricane

b. Tropical Storm d. Tropical Cyclone

Activity 2 – Picture Analysis Direction:

The following pictures below are the correct sequence on typhoon for-
mation. To give you an idea of how it happens, all you have to do is to de-
scribe the 3 pictures below.

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Direction: Number the following events of typhoon formation as to
your own understanding.

______All the heat and air flow toward the eye creating the typhoon.
______The thunderstorms convert the moisture into heat. The heat causes
more air to flow to the center of the storm causing evaporation.
______Typhoons start from tropical thunderstorms. The strong winds pull
in the moisture from the oceans.

HOW TYPHOONS ARE FORMED?

Typhoons start as a tropical thunderstorm. The strong winds pull in

moisture from the ocean

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 What is a Typhoon?

We all know what a typhoon is. or more accurately, we know what to

expect when a typhoon comes. We get a lot of rain and strong
winds. Now, you may not have noticed it but the winds in a typhoon
move in a certain direction. They go around a central area. Take a
look at Figure 1.

Figure 1. A super typhoon as seen from high above the Earth; at the cen-
ter is the” eye” of the super typhoon. Image by NASA Earth Observatory

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The picture shows a super typhoon as viewed from up above the
Earth. A typhoon looks the same, only smaller. See the clouds in a
spiral arrangement? They are being blown by winds in a counter-
clockwise direction. In a super typhoon, the wind speed is greater
than 200 kilometers per hour (kph).

If the wind speed is less, from 119 to 200 kph, then it is called a ty-
phoon. If the wind speed is between 65 and 118 kph, it is called a
tropical storm. When the wind speed is between 35 to 64 kph, it is a
tropical depression.

Tropical depression, tropical storm, typhoon, and superty-

phoon are categories of tropical cyclones (Table 1). In simple terms,
a tropical cyclone is a system of thunderstorms that are moving
around a center. As the winds intensify or weaken, the category is
upgraded or downgraded accordingly.

The term typhoon is used only in the northwestern part of the Pa-
cific Ocean. In the northeastern part of the Pacific Ocean and in the
northern part of the Atlantic Ocean, the equivalent term is hurricane.
Thus, a hurricane on one side of the Pacific Ocean will be called a ty-
phoon if it crosses into the other side

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 In the Philippines, we use the same word for all categories of tropi-
cal cyclones. We call it “bagyo” whether it is a tropical depression, a
tropical storm or a typhoon

Philippine Area of Responsibility

When a weather disturbance enters the Philippine Area of Responsi-

bility (PAR), the weather bureau begins to monitor it. Do you know
where the PAR is? Do the following activity to find out.

ACTIVITY NO.1

PLOTTING THE PAR

Objectives:
After performing this activity, you should be able to:
1. read map,
2. given the latitude and longitude of a tropical cyclone, tell if it has
entered the Philippine Area of Responsibility, and
3. explain what is meant when a typhoon has entered the Philippine
Area of Responsibility.

Materials Needed:
map of the Philippines and vicinity
pencil
Procedure:
1. Plot the following points on the map below (Figure 2).

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 2.Connect the plotted points. The region within is the Philippine Area
of Responsibility or PAR. It is the job of PAGASA to monitor all tropical
cyclones that enter this area.

QUESTIONS TO BE ANSWERED:

Q1. If a typhoon is located at 15°N, 138°E, is it within the PAR?

Q2. How about if the typhoon is at 19°N, 117°E, is it inside the PAR?

Activity 2

Tracking a tropical cyclone

Objectives:

After performing this activity, you should be able to:

1. determine if your location is in the path of a tropical cyclone, given

the latitude and longitude position and

2. explain why PAGASA regularly monitors when a tropical cyclone is

within PAR.

Materials Needed:

map with the PAR (from Activity 1) tracking data pencil

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 a whirlpool is carried along by a flowing stream.

As you can observe, all four tropical cyclones struck the northern
part of the Philippines. Now you know why the southern part of the
Philippines is often untouched by tropical cyclones. Where do you think
should a tropical cyclone form so it would hit the Mindanao area?
Three of the tropical cyclones mentioned above weakened and died
out near land. Agaton dissipated in Luzon, Yoyong in Taiwan, and
Huaning near Mainland China. This means that when tropical cyclones
reach land, they die out because they are cut off from the warm ocean
waters that keep them going.
Now you know where tropical cyclones start to form, why they
form there, and in what direction they generally move. Can you now
explain why the Philippines is prone to typhoons?
In the following activity, you will try your hand in tracking a
tropical cyclone as it enters and leaves the PAR.

ACTIVITY NO. 2

Tracking a tropical cyclone

Objectives:
After performing this activity, you should be able to:
1. determine if your location is in the path of a tropical cyclone, given
the latitude and longitude position and
2. explain why PAGASA regularly monitors when a tropical cyclone is
within PAR.

Materials Needed:
map with the PAR (from Activity 1)
tracking data
pencil

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QUESTIONS TO BE ANSWERED ON A YELLOW/ PAD PAPER

Q1. Where did Sendong form?

Q2. When did Sendong enter the PAR?
Q3. When did Sendong leave the PAR?
Q4. In what direction did Sendong move?

Sendong started out in the Pacific as an area of low pressure.

Since it was just a low-pressure area, it was not given a name then
it intensified into a tropical depression. Again it was not yet given a
name because it was still outside the PAR.

When it finally entered the PAR, it had already strengthened into

a tropical storm. Since it was within the PAR by then, PAGASA gave
it a name—Sendong— from its prepared list. Internationally, the
tropical storm was called Washi.

Sendong brought hours of torrential rains to Mindanao. Some

places received more than 200 mm of rain because with the excess
rain, flash floods, and landslide that took place. Nearly a thousand
people were killed, many in the cities of Cagayan de Oro and
Iligan. Damage to houses, roads, and bridges reached up to 2
billion pesos.

After the Sendong disaster, who would have thought that

another tropical cyclone would again hit Mindanao the following
year. Tropical cyclone Pablo (international name, Bopha) was so
strong it was categorized as a supertyphoon. Clearly, we need to
learn about tropical cyclones in order to survive.

References and Links Tarbuck, E.J., & Lutgens, F.K. (2004). Earth Sci-
ence (10th ed.). First Lok Yang Road, Singapore: Pearson Education
(Asia) Pte Ltd.

Science Learner’ Module G8

May R. Chavez

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References
Cockburn, Carrie. “Explainer: How are Typhoons Formed.” November 11,
2019 p.1. https://www.theglobeandmail.com. Shiel, Willem. Typhoons.
https://slideserve.com
References and Links
Tarbuck, E.J., & Lutgens, F.K. (2004). Earth Science (10th ed.).
First Lok Yang Road, Singapore: Pearson Education (Asia) Pte Ltd. http://
www.pagasa.dost.gov.ph/ http://www.ready.gov/hurricanes http://
www.noaawatch.gov/themes/tropical.php

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 The two sides of a non-vertical fault are known as the hanging
wall and footwall. The hanging wall occurs above the fault
plane and the footwall occurs below it. This terminology comes
from mining: when working a tabular ore body, the miner stood
with the footwall under his feet and with the hanging
wall above him.

DO THESE SLOGAN

Make a slogan about earthquake that make use of the words

focus and epicenter.

References:
USGS: What is a fault and what are the different types?
USGS: Fault
University of Saskatchewan: Fault Types
University of Wisconsin System: Types of Earthquakes & Faults

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 Make a slogan about earthquake that make use of the words focus and
epicenter.

References & Links

Science Learner’s Module
Pia C. Ocampo
May R, Chavez
pp.116-120

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 2

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Cuenca Institute - JUNIOR High School 22 TYPHOON
 Reference:
USGS: What is a fault and what are the different types?
USGS: Fault
University of Saskatchewan: Fault Types
University of Wisconsin System: Types of Earthquakes & Faults

https://www.youtube.com/watch?v=A_ZRtS3QGHw

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 Procedure:

1. Attach the rubber band to the paper clip. Then attach the paper
clip to one end of one box. (See Figure 5. The ruler is included for
scale

2. Place the boxes side by side. Put a toy house on the box with the
rubber band. Then tape (lightly?) the two boxes together as shown in
Figure 6. Important: Do not stick the tape on the boxes too much. The
tape is meant to come off.

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 2. Place the boxes side by side. Put a toy house on the box with the
rubber band. Then tape (lightly?) the two boxes together as shown
in Figure 6. Important: Do not stick the tape on the boxes too much.
The tape is meant to come off

3 With your left hand, hold the box without the rubber band in
place. With your other hand, slowly pull on the rubber band in the
direction shown in Figure 7.

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 QUESTIONS

Q1 What happens to the rubber band?

Q2. Keep on pulling on the rubber band. What happens to the box
attached to the rubber band? Note: The tape is supposed to come off,
so stick it on very lightly.
Q3. What happens to the “house”?
Q4. Which is the “fault” in this setup?

ANSWERS

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 Imagine the boxes as the ground, and the boundary between them as
a fault. Energy from inside the Earth makes the ground move. You
simulate this by pulling on the rubber band. There is no movement
right away because of friction. (What represents friction in the
activity?)
Once friction is overcome, the ground suddenly moves and an
earthquake occurs. Some scientists describe this process as stick and
slip. At first, the rocks are stuck together due to friction. Later, the
rocks suddenly slip, generating an earthquake. Every time a fault
slips, the Earth quakes.
In the activity, there was a sudden jerk, but no shaking. The boxes
did not shake as in a real earthquake. Let us see what the next model
does (shows?).
Directions: Pair the given term according to your observation. Write
your answer on the number below.

1. two box - ___________ a. earthquake

2. fault-_______________ b. shaking
3. as you pull the rubber band______ c. fault
4. a crack on the ground _________ d. frictional force
5. a sudden jolt ____________ e opposing plate

References

Science Learners Module

Pages—115-119

Pia C. campo, May R chavez

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Step 3: place numbers for V and R and divide to find I.
I = 120/50

Complete the table below

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 ANSWERS

SCIENCE LEARNER’ MODULE 8

pages 53-58
Marlene B. Ferido, Ph.D., Ian Kendrich C. Fontanilla, Ph.D.,
Jacqueline Rose M. Gutierrez, Shirley R. Jusayan,

Breaking Through Science 8

pages– 148-153
Sol Saranay M. Baguio

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