4th quarter

Natural hazard

is the treat of an event that will likely have a negative impact 

Disasters

• disruption of the function of a community or a society involving widespread human, material, economic, or environmental losses

• Natural disasters are rarely completely natural.

• It is important to recognize the anthropogenic or human induced factors that have converted the natural hazard into a disaster. 

  
  

4 categories of disasters

Geological, climatological, hydrometeorological, slowly acting process

Geological hazards

caused by internal earth processes and related geophysical processes 

Volcanic eruption

• Volcanism

• occurs when magma escapes through weak spots in Earth’s crust

Effusive eruption

• happens when lava flows out gently from a volcano 

• it is slow and steady, allowing molten rock to move easily across the ground 

Explosive eruption

• happens when magma is thick and traps gas 

• pressure builds up inside the volcano until it bursts violently

Lava flows, pyroclastic flows, ashfall, toxic gases

Volcanic eruptions hazards include:

Active, inactive, potentially active

Classification of volcano

Active

has a recorded history of eruption 

Inactive

has no recorded history of eruption

Potentially active

young looking and has no history of eruption

PHIVOLCS Volcano Alert Levels

a reference guide to understanding the state of an active volcano 

Mount Apo

tallest volcano in the PH

Apolaki Caldera

world’s largest known caldera volcano

Earthquake

• weak to violent shaking of the ground produced by the sudden movement of the rocks materials

• sudden release of energy in the Earth’s crust causes the ground to shake; caused by movement along the fault line

Tectonic and volcano

2 types of earthquake

Tectonic

produced by sudden movementalong faults and plate boundaries

Volcanic

caused by rising magma

Focus or hypocenter

place inside Earth’s crust where an earthquake originates

Epicenter

the point on Earth’s surface directly above the focus

Fault

a fracture between two blocks of rock

Seismic waves

waves of energy that travel through Earth’s layers

Intensity

the strength of an earthquake perceived by people in a certain location

Magnitude

the energy released at the surce/focus of the earthquake

Richter scale

measures earthquake magnitude (strength) logarithmically

PHIVOLCS Earthquake Intensity Scale

• is a seismic scale used and developed by the PHIVOLCS to measure the intensity of earthquakes

• it was developed as upon a specific response to the 1990 Luzon earthquake.

1990 Luzon Earthquake

• occured on July 16, 1990

• recorded magnitude of 7.7

• 1,621 people were killed

Liquefaction

occurs when vibrations cause the soil particles to lose contact with each other, creating excess water pressure

Landslide

• a mass movement of material down a slope

• can happen suddenly or more slowly over long periods of time

• downslope movement of rock, soil, or debris

  • rockfalls

  • mudflows

  • debris flows

Tsunami

• giant waves caused by earthqakes or volcanic eruptions under the sea

• can be also a risk associated with earthquake

Hydrometeorological hazards

phenomena of atmospheric, hydrological, or oceanographic nature

Typhoon

• intense tropical stroms with strong winds and heavy rainfall

• forms over warm ocean waters

• intense tropical cyclone

• with maximun sustained winds of 118 kilometers per hour

• named differently

Tornado

• violently rotating column of air

• in contact witj both the surface of the Earth and the base of a cumolonimbus cloud

• often visible as a funnel-shaped cloud

Flood

• pertains to the overflow of water onto normally dry land

  • river floods

  • flash floods

  • coastal floods

• leads to loss of life, property damage, and soil erosion

Storm surge

an abnormal rise of sea water caused by the strong winds and low pressure of a typhoon or tropical cyclone

Rockfall

occurs when individual rocks or boulders break loose from a steep cliff or slope and fall freely before hitting the ground

Mudflow

• a fast-moving flow of water mixed with soil, clay, and silt

• behaves like wet cement rushing down a slope

Debris flow

a rapid movement of water, rocks, soil, trees, and other debris down a slope

Soil erosion

• gradual removal of tapsoil by wind, water, or ice

• a natural process, accelerated by human activities

Salt water intrusion

• movement of salt water into freshwater aquifers

• impacts water supplies and agriculture

Neolithic period or new stone age

• represents one of the most transformative eras in human history

• a radical shift in hoe human societies organized themselves and interacted with their environment

Neolithic 1

• arrival of Austronesian farmers

• introduction of swidden farming

• small-scale rotational farming

Metal age 2

• more intensive forest clearing with metal tools

• early wet rice cultivation in river valley floodplains

• beginning of permanent agriculture in some areas

Pre-colonial 3

• Ifugao rice terraces (Cordillera)

• coastal settlement

• early river channel modification

Spanish period 4

1565-1898

• hacienda agriculture

• timber extraction for shipbuiling and trade

• forced resettlement to lowlands (reduccion)

American period 5

1898-1946

• commercial logging

• road and railroad construction

• growth of export agriculture and mining

Post-independence 6

1946-1980s

• peak commercial logging era

• dam construction

• rapid urban expansion

Contemporary

1990s-Present

• open-pit mining

• large-scale reclamation (Manila Bay)

• urban sprawl

Human activities

have significantly altered the natural landscapee of the Philippines sinece the Neolithic era, creating both challenges and opportunities

Kaingin

• swidden farming

• the practice of slash and burn agriculture

• involves cutting and burning existing vegetation to clear land for cultivation

Cutting and burning

farmers clear land by cutting down trees and other plants

Ash as fertilizer

the burned vegetation is then cleared away, and the ashes are incorporated into the soil to provide nutrients for the crops

Crop cultivation

various agricultural and agroforestry crops are grown in these cleared areas

Shifting cultivation

where farmers move to a new area of forest after the soil is depleted, repeating the cycle of clearing and burning

Extensive deforestation

Kaingin contributes to significant forest loss in the PH

Soil erosion and degradation

• burning removes tree roots that stabilize the soil, causing erosion and landslides

• ash temporarily fertilizes the soil, but fertility soon declines, necessitating new clearing of forest land

Loss of soil fertility

continous shifting cultivation exhausts soil nutrients, diminishing agricultural productivity and raising concerns for long-term sustainability

Deforestation

severe environmental issue in the PH primarily due to urbanization

Increased CO2 emission

deforestation contributes to the release of caron dioxide into the atmosphere

Soil erosion and landslide

removal of forest cover increases soil erosion and the risk of landslides and flashfloods

Ecosystem damage and biodiversity loss

the destruction of forests eliminates the habitat and food sources for many unique and threatened species, leading to a high risk of extinction

Reclamation

involve creating new land from water bodies for development purposes

Hazard, exposure, vulnerability

3 components of risk

Hazard

is a process, phenomenon, or human activity that may cause loss of life, injury, property damage, and more

Exposure

the situation of people, property, systems and other elements present in hazard zones is therefore subject to potential loss

Vulnerability

the characteristics and circumstances of a community, system, or asset that make it susceptible to the damaging effects of a hazard

iHEAT

• is a monitoring and warning tool developed by the PAGASA

• provides heat index maps and forecasts across the PH

• helps people understand the level of heat stress

Interactive Heat Index Monitoring and Prediction

iHEAT

Color coded heat index levels

the map uses colors to represent different heat danger levels

Geographics coverage

the map displays heat index values across different regions of the PH

• cities

• provinces

• weather monitoring stations

Forecast information

the iHEAT system provides daily heat index forecasts

Heat cramps

painfful muscle spasms caused by dehyration

Heat exhaustion

symptoms include dizziness, nausea, and heavy sweating

Heat stroke

severe condition where body temperature exceeds 40C and can be fatal

RA 10121

Philippine Disaster Risk Reduction and Management Act of 2010

Prevention and mitigation

eliminate or reduce the probability of a disaster

Preparedness

ensure effective response and reduce lossess during a disaster

Response

actions taken during or immediately after a disaster to save lives, reduce impacts, and begin recovery

Recovery and rehabilitation

to restore conditions to acceptable levels after a disaster

Preparedness

• it is important that u are prepares for potential disasters depending on your location

• having an emergency supply kit and an emergency plan are two basic steps to be prepared

Jupiter

has a faint, dusty ring system discovered in 1979

Saturn

features the most extensive and brilliant ring system, primarily composed of water ice

Uranus

possesses thin, dark, narrow rings

Neptune

has faint, dark rings that include unique, incomplete “ring arcs”

Earth

• living planet

• known planet that can sustain life

Goldilocks planet

Earth is often called as this because its conditions are just right

Elliptical orbit

Earth’s distance from the sun varies throughout the year due to this

Perihelion

the sun is closest to earth in january

Aphelion

the sun is farthest to earth in july

Astronomical unit AU

• is the distance within our solar system

• =150 MILLION KM (93 million miles)

Saturn

the most numbers of satellite and it has 200+ moons

Asteroid belt

in between terrestrial planets and jovian planets, separating them

Terrestrial planets

• rocky planets located inside the asteroid belt

• has a concrete solid surface

Jovian planets

• gas giants, located outside the asteroid belt

• made up of large amount of gas

Permafrost

existing as vast, shallow-to-deep deposits of ground water ice beneath the surface

Jupiter’s red spot

a storm that reached the planets for century

Jupiter, saturn, uranus, neptune

4 jovian planets JSUN

Atmosphere

• gaseous envelope that surrounds the earth

• protective layer that protects us from external factors

• 5 layers

Meteor

rock burning up as a streak of light in the atmosphere