This document defines typhoons and their development. It explains that typhoons form over warm ocean waters through the process of cyclogenesis, where converging winds and rising humid air lead to the formation of clouds and rotating storm systems. The Philippines is prone to typhoons because it is located in the western Pacific Ocean, an area where typhoons frequently develop and make landfall due to its warm waters and location within the typhoon belt.

1. ALARMING
TYPHOONS
OBJECTIVES (DAY 1)
• DEFINE TYPHOONS
AND DISCUSS ITS
DIFFERENT TERMS.
• EXPLAIN HOW
TYPHOONS DEVELOP.
• INFER WHY THE
PHILIPPINES IS PRONE
TO TYPHOONS.
SCIENCE 8
PREPARED BY: LOUIE JANE T.

2. KEY CONCEPTS
• PRESSURE - THE CONTINUOUS PHYSICAL FORCE EXERTED
ON OR AGAINST AN OBJECT BY SOMETHING IN CONTACT
WITH IT.
• ATMOSPHERIC PRESSURE - SOMETIMES ALSO CALLED
BAROMETRIC PRESSURE, IS THE PRESSURE WITHIN THE
ATMOSPHERE OF EARTH.
• LOW PRESSURE - IS A REGION WHERE THE
ATMOSPHERIC PRESSURE IS LOWER THAN THAT OF

3. KEY CONCEPTS
• CONVERGENT WIND – THE DIFFERENCE BETWEEN
HIGH AND LOW PRESSURE SYSTEMS IN THE
ATMOSPHERE CREATING WINDS.
• HUMIDITY - A QUANTITY REPRESENTING THE
AMOUNT OF WATER VAPOR IN THE ATMOSPHERE OR
A GAS.

4. WHAT IS WEATHER?
•WEATHER IS A DAY-TO-DAY CONDITION OF
THE ATMOSPHERE AT A PARTICULAR TIME
AND PLACE.
•WEATHER TAKES PLACE AT THE
TROPOSPHERE.
•WEATHER CHANGES FROM DAY-TO-DAY
BECAUSE THE AIR IN THE ATMOSPHERE IS

6. CLOUD WATCH
Cirru
s
Cumulus
Cirrocumul
us
Stratocumulu
s Nimbu
s
Clear
Sky

7. WEATHER WATCH
Anemomet
er
Rain
Gauge
Thermome
ter
Barometer

8. TYPHOON
HURRICANE
CYCLONE

9. Hurricane
Florence
Tropical Cyclone
Ingrid
Super Typhoon Haiyan

10. PARTS OF A TYPHOON
• EYE -- THIS IS THE CENTER.
IT IS THE CALM PART OF
THE STORM.
• EYE WALL -- THIS PART IS
AROUND THE EYE. THIS
PART HAS THE STRONGEST
WINDS AND RAINS. THE
WINDS MAY BLOW 200
MILES PER HOUR.
• RAIN BANDS -- THESE ARE

11. PARTS OF A TYPHOON

12. DEVELOPMENT OF A TYPHOON
(TROPICAL CYCLONE)
CYCLOGENESIS
• THE PROCESS BY
WHICH A
CYCLONE
DEVELOPS AND
STRENGTHEN

13. THE FORMATION OF A TYPHOON INVOLVES
THE FOLLOWING PROCESSES:
1. EVAPORATION OF WATER AT OCEAN SURFACE TEMPERATURE
OF 26.5 DEGREE CELSIUS.
2. CONVERGENCE OF AIR MASSES OF DIFFERENT
CHARACTERISTICS.
3. HIGH HUMIDITY
4. WARM AIR RISES TOWARD THE COOLER PARTS OF THE
ATMOSPHERE, IT COOLS OFF AND THE WATER VAPOR BEGINS
TO FORM CLOUDS.

14. WHY PHILIPPINES A TYPHOON-PRONE
AREA?

15. DEADLIEST CYCLONES

16. GENERALIZATION
•WHAT IS TYPHOON AND HOW IS IT
DIFFERENT FROM HURRICANE AND
CYCLONE?
•HOW ARE TYPHOONS FORMED?
•WHY PHILIPPINES IS PRONE TO TYPHOONS?