This describes the dangers of cyclones and other natural disasters

1. UNIT 1 CHAPTER 4
DANGER ZONE
Reported by Eman Madoh

2. UNDER THIS CHAPTER…
I. NATURAL PROCESSES AND HAZARDS
II. HYDROMETEOROLOGICAL PHENOMENA AND HAZARDS
III. MARINE AND COASTAL PROCESSES AND HAZARDS

3. CONCEPT MAP
Natural
Processes
geological
earthquake
volcanic eruption
landslide
tsunami
hydrometeorological
tropical cyclone
monsoon
flood
tornado
coastal
erosion
submersion
saltwater intrusion
such as
cause cause cause

4. NATURAL PROCESSES AND
HAZARDS

5. The natural phenomena involving geologic, hydrometeorological, and marine and coastal
processes could lead to natural disasters.
A natural hazard is a naturally-occurring event or phenomenon that has negative anthropogenic
and environmental effects.

6. A natural disaster is any natural hazard or
threat that causes fatality or damage to
property.

7. Hazard Mitigation
Even though the risk from natural
hazards cannot be eliminated, they
could be understood enough to
minimize the hazards, and, in effect,
risks.
describes actions taken to help reduce or
eliminate long-term risks caused by hazards
or disasters

8. Geologic Hazards and
Mitigation
The processes that have shaped Earth continually act
on or beneath the surface.
Geologic hazards brought by earthquakes,
earthquake-induced landslides, volcanic eruption, and
tsunamis are due to the movement of plates and local
concentration of geologic heating.

9. Earthquakes
Due to the Philippine’s location within the Pacific Ring of Fire, there have been
earthquake events in all parts of the Philippines (except for Palawan).
Since 1968, the Philippine Institute of Volcanology and Seismology (PHIVOLCS), the
government agency monitoring all seismic and volcanic activities in the Philippines, has
recorded 12 destructive earthquakes.

11. Top Ten Provinces that are
at Risk for Earthquakes
1. Surigao del Sur
2. La Union
3. Benguet
4. Pangasinan
5. Pampanga
6. Tarlac
7. Ifugao
8. Davao Oriental
9. Nueva Vizcaya
10. Nueva Ecija

12. https://www.phivolcs.dost.gov.ph/index.php

13. Landslides
When earthquakes happen in humanmade embankments and natural slopes in
mountainous areas, the hazard and potential devastation greatly increases.
Most of the provinces are susceptible to landslide hazards.

14. Top Ten Provinces that are
at Risk for
Earthquake-induced
Landslides
1. Ifugao
2. Lanao del Sur
3. Sarangani
4. Benguet
5. Mountain Province
6. Bukidnon
7. Aurora
8. Davao del Sur
9. Davao Oriental
10. Rizal

15. Volcanic Eruptions
The Pacific Ring of Fire describes the distribution of most volcanoes in the Philippines.
There are 22 historically-active volcanoes distributed all over the Philippine
archipelago.
Since volcanoes are not present in some provinces, these particular areas have no risk
to volcanic eruptions.

16. Howel Williams
Howel Williams was a world-famous
volcanologist known as the father of modern
volcanology. He finished his bachelor’s
degree in geography in 1923 and master’s
degree in archeology in 1924 at the
University of Liverpool.

17. Williams was most notable for his
work on Crater Lake National Park
in California, where her cited the
nature and collapse of the crater.

18. Top Ten Provinces that are
at Risk for Volcanic
Eruptions
1. Camiguin
2. Sulu
3. Biliran
4. Albay
5. Bataan
6. Sorsogon
7. South Cotabato
8. Laguna
9. Camarines Sur
10. Batanes

19. Tsunamis
The Philippines is constantly at risk for tsunami.
Most coastal areas have higher hazard potential.

20. Top Ten Provinces that are
at Risk for Tsunamis
1. Sulu
2. Tawi-tawi
3. Basilan
4. Batanes
5. Guimaras
6. Romblon
7. Siquijor
8. Surigao del Norte
9. Camiguin
10. Masbate

21. Earthquake Engineering To be earthquake-proof, buildings,
structures, and their foundations need to be
built to be resistant to sideways loads.

22. HYDROMETEOROLOGICAL PHENOMENA
AND HAZARDS

23. A monsoon is a consistent reversal of wind pattern or wind system generated by a large
weather affecting a large area over a period of several months.
There are two prevailing wind
patterns which affect the
Philippines:
❖ southwest monsoon (locally
known as Habagat) – occurs
within May to October
❖ northeast monsoon (locally
known as Anihan) – occurs
within November-February
The southwest monsoon brings heavy rain to the Philippines, with the highest percentage of
rainfall attributed to the occurrence of tropical cyclones.

24. Tropical cyclone or bagyo
a rapid rotating storm originating over tropical oceans from where it draws the energy to
develop
The Philippine Atmospheric, Geophysical,
and Astronomical Services Administration
(PAGASA) is the government weather
bureau that monitors atmospheric
conditions within the Philippine Area of
Responsibility (PAR), its
internationally-recognized jurisdiction.
PAGASA records an average of 20 tropical
cyclones entering the PAR annually, with
about five being destructive.

25. There are five categories of tropical cyclones based on their wind
speed
TYPE Sustained Wind Near the Center
Tropical depression 30-60 km/h
Tropical storm 61-88 km/h
Severe tropical storm 89-117 km/h
Typhoon 118-219 km/h
Super typhoon faster than 220 km/h

26. Typhoon-risk in the
Philippines

27. Tropical Cyclone & Flooding
Mitigation and Prevention
To mitigate the effects of tropical
cyclones and flooding, PAGASA
has implemented some measures.

28. Floods and 3-D Hazard
Maps
Floods and 3-D hazard maps are made and
disseminated to areas which are usually hit by
typhoons and areas which are prone to
flooding.

29. public storm warning
signal (PSWS)
PAGASA issues public weather
forecasts and advisories called public
storm warning signal (PSWS) in several
mass media to provide warnings
related to weather conditions.
Level Wind and Lead Time
1 30-60 km/h; within 36
hours
2 61-100 km/h; within 24
hours
3 101-185 km/h; within 18
hours
4 186-220 km/h; within 12
hours
5 faster than 220 km/h;
within 12 hours

30. Using PAGASA’S PSWS, the Department of Education (DepEd) has
adopted the following guidelines with regards to class suspension:
PSWS 1 – All classes in kindergarten are suspended
PSWS 2 – All classes in elementary and high school are suspended
PSWS 3 – All classes in all levels, including college and graduate schools, are suspended

31. color-coded rainfall
warning system
Aside from the PSWS. PAGASA also
provides color-coded rainfall warning
system in their storm forecasts to help
communities prepare for incoming
heavy rain and potential flooding, and
act accordingly.

32. Dr. Carlo Arcilla
Dr. Carlo Arcilla specializes in igneous
petrology and geochemistry, and
country’s leading expert on the
geochemistry and geology of the
Philippine ophiolites. Dr. Arcilla is also
involved In hazard assessment in the
Philippines including natural weather
disasters, earthquake hazards, and
mining.

33. Nationwide
Operational
Assessment of Hazards
(NOAH)
One of the many programs that the
Philippine government has
undertaken to address disaster
prevention and mitigation in the
country.

34. Nationwide
Operational
Assessment of Hazards
(NOAH)
The NOAH program currently has nine
projects under their wing, including
advanced disaster science research
and technologies. In one of their
projects, they have provided the
public with high-resolution flood
hazard maps which are useful in
identifying areas prone to flooding.

35. MARINE AND COASTAL
PROCESSES AND HAZARDS

36. Coastal area refers to the land and sea areas bordering the shoreline. It comprises the natural
boundary between the land and ocean which may include the beach, dunes, mangroves,
estuary, delta, or lagoon, among others.
The hazards of living near the coastlines include dangers of waves, tides, erosion, flood or
submersion, and saltwater intrusion.

37. Submersion and Coastal
Erosion
The process of wave action, wave currents,
and tidal wear away the land and remove
sediments near the coastline. This effect is
called coastal erosion.

38. Submersion and Coastal
Erosion
Waves, which are caused by wind and storm,
cause large impacts around the coastline.
Tides, which are the result of the gravitational
attraction of the sun and moon on the oceans,
cause the frequent rise and fall of ocean
levels.

39. Hydrologists are involved in monitoring, managing, and protecting the Earth’s water and water
resources. They engineer pipes and channels that would make the flow of water more effective,
efficient, and sustainable.
Their work involves efficient planning, development, and sustainable use of water resources.

40. Seawall and Groynes
To prevent flooding and erosion,
structures can be built to attempt to
stop the transport of sand, uncontrolled
rise of sea level, and the forces of waves
and tides.

41. Seawall and Groynes
Building seawalls which run parallel to
the sea prevents the direct impact of
coastal processes to landforms near the
coast.
Groynes are built perpendicular to the
beach to limit the movement of
sediment and interrupt the natural flow
of water and waves.

42. Saltwater Intrusion
When saline water moves into freshwater aquifers, which are the main source of drinking water
in coastal areas, it leads to contamination. Intrusion of saltwater happens naturally because of
the varying densities of saltwater and freshwater.

43. Saltwater Intrusion
To mitigate the effects of saltwater intrusion, injection wells are built where freshwater is
injected. The addition of freshwater in injection wells creates a hydraulic pressure or barrier to
saltwater intrusion.

44. The Changing
Climate
The Earth’s climate has changed
throughout history. Within the last
650,000 years, there have been seven
glaciations – the last one occurred 7,000
years ago. Most of these climatic changes
are attributed to very small variations in
the Earth’s orbit that changed the amount
of solar energy Earth receives.

45. Thanks for listening!
:3
BUT WAIT!

46. yes you

47. Assessment
Answer the question as follows.
Please get a 1/4th
sheet of paper and;
Don’t worry, kaya niyo yan owo
15 items

48. I. Multiple Choice
Write the letter of your answer.
1. Which of the following is not a hazard caused by natural processes?
a. geological hazards
b. hydrometeorological hazards
c. environmental effects
d. coastal hazards

49. I. Multiple Choice
Write the letter of your answer.
2. This refers to any natural hazard or threat that causes fatality or damage to property.
a. natural phenomena
b. natural disaster
c. natural occurrence
d. natural process

50. I. Multiple Choice
Write the letter of your answer.
3. These are developed to illuminate areas that are affected or vulnerable to a
particular hazard.
a. world map
b. heatmap
c. road map
d. hazard maps

51. I. Multiple Choice
Write the letter of your answer.
4. This occurs when gas and//or lava are released from a volcano, it can sometimes
happen explosively.
a. volcanic eruption
b. earthquake
c. earthquake-induced landslides
d. landslide

52. I. Multiple Choice
Write the letter of your answer.
5. This refers to the sudden violent movement of the Earth’s surface.
a. volcanic eruption
b. earthquake
c. earthquake-induced landslides
d. landslide

53. I. Multiple Choice
Write the letter of your answer.
6. This is a consistent reversal of wind pattern or wind system generated by a large
weather system affecting a large area over a period of several months.
a. monsoon
b. southwest monsoon
c. tropical cyclone
d. northeast monsoon

54. I. Multiple Choice
Write the letter of your answer.
7. Which of the following is not a measure implemented by the PAGASA for the effects
of tropical cyclones and flooding?
a. flood hazard maps
b. color-coded rainfall warning system
c. FaultFinder
d. public storm warning signal

55. I. Multiple Choice
Write the letter of your answer.
8. Which of the following statements is true regarding coastal areas and hazards?
a. Living in coastal areas is dangerous and does not provide any benefits.
b. The hazards of living near coastlines include dangers of waves, rides, erosion, flood,
and saltwater intrusion.
c. The Philippines is not susceptible to coastal hazards despite being an archipelago
located in the tropics.
d. There is nothing that can be done to prevent coastal and marine hazards from
occurring.

56. II. True or False
Write True if the statement is true; otherwise, write False.
________ 9. The Earth’s climate has remained the same throughout history.
________ 10. PHIVOLCS is the government agency monitoring all seismic and volcanic
activities in the Philippines.
________ 11. All areas in the Philippines are at risk to volcanic eruptions.
________ 12. Tropical cyclones are common in the Philippines.
________ 13. The PSWS currently uses a four-level warning system to this day.
________ 14. A natural hazard is a naturally-occurring event or phenomenon which has
negative anthropogenic and environmental effects.
________ 15. Seismic or volcanic activity can cause other natural hazards.