8/4/2021
SURVAYING THE KEY CONCEPTS
AGE 405: Geography of
Introduction:
Hazards
The terms hazards, disaster,
Instructor: vulnerability and risk are often
used interchangeably although each
Dr. Calvine Kayi has a precise and distinct meaning.
email:
These terms may be defined as
follows:
Hazard cont..:
Hazard:
For instance, a flood in an unoccupied
Refers to a potentially damaging or an unused flood plain is a hazard
physical event, phenomenon, or and nothing more. Similarly an
human activity that may cause the earthquake in a remote unpopulated
loss of life or injury, damage to area is also a hazard. In other words,
property, and/or lead to social and hazards are threats to people, and
economic disruption as well things they value and are, in part,
environmental degradation. socially constructed by people‘s
perceptions and their experiences.
Hazard cont..: Vulnerability:
The perceptions may vary by culture, Refers to the conditions
gender, race, socioeconomic status, determined by physical,
and political situation. socioeconomic and environmental
Hazards can be singular, sequential, factors or processes which
or combined in their origin and increase an individual‘s or
effects. Each hazard is society‘s, or community‘s
characterized by its location,
intensity, frequency & probability. exposure to adverse effects
and/or impacts of hazards.
1
, 8/4/2021
Risk: Risk is expressed in terms of
likelihood, chance or probability
This is a measure of of any event of a given size
vulnerability of a particular area occurring.
to events of a given size or The evaluation of risks may be
magnitude that can cause loss of based on records of past events,
life or injury, damage to and the longer and more detailed
property, social and economic the records, the better the
disruption, or environmental estimation of risks.
degradation.
Disaster: When an extreme event occurs in
areas occupied or used by people the
effects of these events is what is
It is a sudden damaging or calamitous called a disaster or a catastrophe.
event that seriously disrupts the
functioning of a community, or
society and causes human, material, For a disaster to be entered into the
socioeconomic or environmental database of the United Nations‘
losses that exceed the community‘s International Strategy for Disaster
or society‘s ability to cope using its Reduction (ISDR), at least one of the
own resources. following criteria must be met:
(a) A report of 10 or more people CLASSIFICATION OF DISASTERS
killed. Disasters arise from many
(b) A report of 100 or more people different situations, but many of
affected. the typologies use the causes or
(c) A declaration of state of origins of disasters as the
emergency by the relevant classifying principle.
government
In most cases, however, disasters
(d) A request by the national are multi-causal. Thus single-cause
government for international based typologies are not the best.
assistance.
2
, 8/4/2021
The following description provides a -In other words, these are events
broad classification of three types associated with normal*
of disasters: geophysical and biological
a) Natural disasters processes that cause death,
-Are major adverse events resulting injury or loss of home, property
from natural processes of the Earth; or income.
e.g. floods, hurricanes, tornadoes, * the intensity of the hazard may be influenced
volcanic eruptions, earthquakes, by human modifications of the landscape (e.g.
tsunamis, storms, and other geologic deforestation and urbanization influence flood
frequency and magnitudes) or climate (e.g. heat
processes. waves in urban areas).
Natural disasters can further be ii. Geological
classified as follows: -Include internal earth processes of tectonic
origin such earthquakes, faulting, Tsunamis,
i. Hydro-meteorological volcanic eruption, as well as external processes
-Are natural processes or phenomena that are such as mass movement of landslides, rock
atmospheric, hydrological or oceanographic in falls among others.
nature that may cause loss of life, or injury, -These phenomena vary regionally and
property damage, socioeconomic disruption or seasonally and may trigger secondary
environmental degradation. disasters. For example, landslides and
-Hydro-meteorological disasters include Tsunamis can follow earthquakes.
floods, mud-flows, tropical cyclones, thunder Thunderstorms may be accompanied by heavy
and hailstones, blizzards, frost, drought, rains that can cause mudflows, flash floods,
wildfires, permafrost, heat waves, sand and and conventional flooding.
dust storms, snow and ice avalanches etc.
iii. Biological -In addition, a wide range of diseases
are caused or transmitted by
-These are processes of organic origin organisms and are considered
or those conveyed by biological vectors biological disasters.
including exposure to pathogenic micro- -Examples of biological disasters
organisms, toxin and bioactive include outbreaks of epidemic diseases
substances, which may cause loss of life
or injury, property damage, such as Covid-19, HIV/AIDS,
socioeconomic disruption or typhoid, cholera, wheat stem rust,
environmental degradation. rabies, rinderpest, foot and mouth,
and plagues such as locusts,
armyworms and water hyacinth etc.
3
SURVAYING THE KEY CONCEPTS
AGE 405: Geography of
Introduction:
Hazards
The terms hazards, disaster,
Instructor: vulnerability and risk are often
used interchangeably although each
Dr. Calvine Kayi has a precise and distinct meaning.
email:
These terms may be defined as
follows:
Hazard cont..:
Hazard:
For instance, a flood in an unoccupied
Refers to a potentially damaging or an unused flood plain is a hazard
physical event, phenomenon, or and nothing more. Similarly an
human activity that may cause the earthquake in a remote unpopulated
loss of life or injury, damage to area is also a hazard. In other words,
property, and/or lead to social and hazards are threats to people, and
economic disruption as well things they value and are, in part,
environmental degradation. socially constructed by people‘s
perceptions and their experiences.
Hazard cont..: Vulnerability:
The perceptions may vary by culture, Refers to the conditions
gender, race, socioeconomic status, determined by physical,
and political situation. socioeconomic and environmental
Hazards can be singular, sequential, factors or processes which
or combined in their origin and increase an individual‘s or
effects. Each hazard is society‘s, or community‘s
characterized by its location,
intensity, frequency & probability. exposure to adverse effects
and/or impacts of hazards.
1
, 8/4/2021
Risk: Risk is expressed in terms of
likelihood, chance or probability
This is a measure of of any event of a given size
vulnerability of a particular area occurring.
to events of a given size or The evaluation of risks may be
magnitude that can cause loss of based on records of past events,
life or injury, damage to and the longer and more detailed
property, social and economic the records, the better the
disruption, or environmental estimation of risks.
degradation.
Disaster: When an extreme event occurs in
areas occupied or used by people the
effects of these events is what is
It is a sudden damaging or calamitous called a disaster or a catastrophe.
event that seriously disrupts the
functioning of a community, or
society and causes human, material, For a disaster to be entered into the
socioeconomic or environmental database of the United Nations‘
losses that exceed the community‘s International Strategy for Disaster
or society‘s ability to cope using its Reduction (ISDR), at least one of the
own resources. following criteria must be met:
(a) A report of 10 or more people CLASSIFICATION OF DISASTERS
killed. Disasters arise from many
(b) A report of 100 or more people different situations, but many of
affected. the typologies use the causes or
(c) A declaration of state of origins of disasters as the
emergency by the relevant classifying principle.
government
In most cases, however, disasters
(d) A request by the national are multi-causal. Thus single-cause
government for international based typologies are not the best.
assistance.
2
, 8/4/2021
The following description provides a -In other words, these are events
broad classification of three types associated with normal*
of disasters: geophysical and biological
a) Natural disasters processes that cause death,
-Are major adverse events resulting injury or loss of home, property
from natural processes of the Earth; or income.
e.g. floods, hurricanes, tornadoes, * the intensity of the hazard may be influenced
volcanic eruptions, earthquakes, by human modifications of the landscape (e.g.
tsunamis, storms, and other geologic deforestation and urbanization influence flood
frequency and magnitudes) or climate (e.g. heat
processes. waves in urban areas).
Natural disasters can further be ii. Geological
classified as follows: -Include internal earth processes of tectonic
origin such earthquakes, faulting, Tsunamis,
i. Hydro-meteorological volcanic eruption, as well as external processes
-Are natural processes or phenomena that are such as mass movement of landslides, rock
atmospheric, hydrological or oceanographic in falls among others.
nature that may cause loss of life, or injury, -These phenomena vary regionally and
property damage, socioeconomic disruption or seasonally and may trigger secondary
environmental degradation. disasters. For example, landslides and
-Hydro-meteorological disasters include Tsunamis can follow earthquakes.
floods, mud-flows, tropical cyclones, thunder Thunderstorms may be accompanied by heavy
and hailstones, blizzards, frost, drought, rains that can cause mudflows, flash floods,
wildfires, permafrost, heat waves, sand and and conventional flooding.
dust storms, snow and ice avalanches etc.
iii. Biological -In addition, a wide range of diseases
are caused or transmitted by
-These are processes of organic origin organisms and are considered
or those conveyed by biological vectors biological disasters.
including exposure to pathogenic micro- -Examples of biological disasters
organisms, toxin and bioactive include outbreaks of epidemic diseases
substances, which may cause loss of life
or injury, property damage, such as Covid-19, HIV/AIDS,
socioeconomic disruption or typhoid, cholera, wheat stem rust,
environmental degradation. rabies, rinderpest, foot and mouth,
and plagues such as locusts,
armyworms and water hyacinth etc.
3
