CLASS: VIII

SUBJECT: Geography

CHAPTER: Natural and man-made disasters

CHAPTER 5 : NATURAL AND MAN-MADE DISASTERS

EXPLANATION:

A disaster is a serious disruption occurring over a short or long

period of time that causes widespread human, material, economic

or environmental loss which exceeds the ability of the affected

community or society to cope using its own resources.

Disasters are routinely divided into natural or human-made.

Types of disasters:

(i)Natural disasters:

A natural disaster is a major adverse event resulting

from natural processes of the Earth. ( beyond the control of

human beings)

Examples: floods, hurricanes, tornadoes, volcanic

eruptions, earthquakes, tsunamis, storms, and

other geologic processes.

(ii)Man-made disasters:

Man-made disasters are those for which human beings

themselves are responsible.

Examples: wars, riots, nuclear explosions, industrial accidents,

etc.

Disaster Management:

Disaster management is a planned steps taken to

minimize the effects of a disaster.

In general, it is a continuous process by which all individuals,

groups and communities manage hazards in an effort to

avoid pr minimize the impact of disasters resulting from

hazards.

Need for disaster management:

Disaster management aims to reduce, or avoid, the

potential losses from hazards, assure prompt and

appropriate assistance to victims of disaster, and achieve

rapid and effective recovery.

Disaster management is an important component of all the

communities. History has shown us that where communities

have been prepared to face disasters, lesser lives have been

lost, less significant damage to the environment has

occurred, and property has been better conserved.

Phases of disaster management:

Migration: Its aim is to minimise the effects of disaster

through building codes and zoning; vulnerability analyses;

public education.

Preparedness: It focuses on understanding how a

disaster might impact the community and how education,

outreach and training can build capacity to respond to and

recover from a disaster.

Response: The aim of emergency response is to provide

immediate assistance to maintain life, improve health and

support the morale of the affected population. Search and

rescue; emergency relief are important components of

response.

Recovery: It is fourth phase of disaster management. It

includes actions taken to return to a normal or an even safer

situation following an emergency. Getting financial

assistance, temporary housing, medical care are important

components of recovery phase.

Flood

A flood is an abnormal rise of river or any water body due to

heavy rainfall, tsunami, cyclone etc.

Floods are the most common and wide spread of all natural

disasters. India is one of the highly flood prone countries in

the world. Though it is not possible to control the flood

disaster totally, by adopting suitable structural and non -

structural measures the flood damages can be minimised.

Before a Flood

Avoid building in a floodplain.

Construct barriers to stop floodwater from entering

your home.

If a flood is likely in your area, listen to the radio or

television for information.

Know the difference between a flood watch and flood

warning. A watch means flooding is possible. A warning

means flooding is occurring or will occur soon.

When a flood is imminent

Be prepared! Pack a bag with important items in case

you need to evacuate. Don’t forget to include needed

medications.

If advised to evacuate your home, do so immediately.

If there is any possibility of a flash flood, move

immediately to higher ground.

If possible, bring in outdoor furniture and move

essential items to an upper floor.

Turn off utilities at the main switches.

Disconnect electrical appliances.

During a flood

Do not walk through moving water.

Use a stick to check the firmness of the ground in front

of you.

Do not drive into flooded areas. If floodwaters rise

around your car, abandon the car and move to higher

ground if you can do so safely.

Do not touch electrical equipment if you are wet or

standing in water.

After a flood

Listen for news reports to learn whether the community

and water supply is safe to drink.

Avoid floodwaters; water may be contaminated by oil,

gasoline, or raw sewage.

Be aware of areas where floodwaters have receded.

Return home only when the authorities indicate it is

safe.

Stay out of any building if it is surrounded by

floodwaters.

Earthquake

It is the trembling or sudden shaking of ground that happens

when rock masses on the earth’s surface are abruptly

displaced.

Indoors

Do not rush outside, get your family into doorways,

under the tables, or, if they are bedridden, under their

beds; keep away from windows and chimneys.

Outdoors

Stay away from buildings, high walls or dangling electric

wires.

Do not re-enter damaged buildings.

Driving

If you feel the earthquake when riding in a car or bus,

ask the driver to pullover and stop. Stay inside the

vehicle.

As soon as you can

Put out all the domestic fires and turn off heaters.

Turn off electricity, gas and water, if the house is

damaged.

Leave the house if a fire starts that cannot be put out at

once.

Move to the nearest shelter or evacuate the area if this

is ordered by the appropriate government agency.

Fire

As long as fire is under our control, it serves a lot of useful

purposes for us, but, once it goes out of our control, it can

create a lot of destruction.

What to do in case of a fire

Immediately pull the nearest fire alarm pull station as

you exit the building.

When evacuating the building, be sure to feel doors for

heat before opening them to be sure there is no fire

danger on the other side.

If there is smoke in the air, stay low to the ground,

especially your head, to reduce inhalation exposure.

Do’s

Use I.S.I. Certified appliances.

Use good quality fuses of correct rating, miniature

circuit breakers and earth leakage circuit breakers.

Switch off the electric supply of the fire affected areas.

Replace broken plugs and switches.

Switch off the ‘Main’ switch when leaving home for a

long duration.

Elder’s supervision is a must when children play with

firecrackers.

It is safe to play firecrackers in open grounds and open

places.

Don’ts

Don’t use substandard fixtures, appliances.

Never have temporary or naked joints on wiring.

Don’t lay wires under carpet, mats or doorways. They

get crushed, resulting in short circuiting.

Role of government in disaster management

The Central Government supplements the efforts of the State

Government by providing financial and logistic support.

The Ministry of Home Affairs is the Nodal Ministry at the

Centre for coordinating disaster management activities for all

natural hazards. National Disaster Management Authority is

the apex body which lays down the policies, plans and

guidelines for Disaster Management to ensure timely and

effective response to disaster.

The district administration is the focal point for

implementation of all governmental plans and activities. The

actual day-to-day function of administering relief is the

responsibility of the District Magistrate/ District Collector/

Deputy Commissioner who exercises coordinating and

supervising powers over all the departments at the district

level. District Disaster Management Committee involves

people from various blocks and villages.

CASE STUDY -1

Floods in Assam and Bihar

As like as the other calamities, flood is the most devastating

natural calamity that effects Assam and Bihar every year.

Barak and Brahmaputra are important rivers of Assam. Kosi

one of the largest tributary of the river Ganga is known as

‘Sorrow of Bihar’ as it has caused widespread human

suffering in the past due to flooding and very frequent

changes in course.

The river of Bihar and Assam carry high discharge and

very high sediment load and drops it in the plains. The

silt deposits raises the river beds causing widespread

floods.

A majority of the rainfall in this region is concentrated in

the 3 months of monsoon during which the flow of

rivers increases.

Over the years destruction of wetlands and filling up of

the natural catchment areas, rapidly increasing

population, rising urbanization and faulty planning

without taking into consideration the natural contours

of water flow are the major factors responsible for

floods.

Effects of flood

The effects of flood are diverse and manifold which effects

the land, roads, and other means of communication, water,

forests, wildlife, beels, agriculture livestock and all these

leading to diverse effects on biodiversity, ecology and

environment.

Soil erosion and degradation of land and water leads to

damage of the production base, thus adversely affecting

the sustainable agriculture as well as development.

Floods also leads to the damage of irrigation channels.

The irrigation channels in the flood prone areas either

damaged or covered with soil.

Large scale damages are seen on the live-stock and

population. Heavy floods wash away and kill the live-

stocks such as domestic and wild animals. People are

also affected by floods in various ways such as washed

way or attacked by diseases after flood.

Every year, Brahmaputra floods the national park, thus

forcing animals to encroach into human settlements.

This leads to man-animal conflict, making animals

vulnerable to poaching and road accidents.

CASE STUDY-2

Earthquake in Nepal (2015)

Earthquakes constitute one of the most terrible natural

hazards which often turn into disaster causing extensive

devastation and loss of human lives and their properties.

Earthquake of Nepal and India along the Himalayan belt

were caused mainly due to collision of Indian plate and

Eurasian plate.

The earthquake resulted in a significant loss of standing

crops : wheat, barley and potato (close to harvest in

higher altitude areas) and maize (newly planted in lower

altitude areas).

Earthquake also damaged additional food storage

facilities reducing already limited stocks. Malnutrition

rates in certain areas of Nepal are among the highest in

the world.

Water supplies were severely affected increasing public

health risks including the spread of WASH related

disease.

Key infrastructure – including schools, health facilities,

access roads, temples and heritage sites – were

damaged or destroyed.

Over 1,000 health facilities were destroyed or severely

damaged including primary health care centres, village

health posts and birthing centres.

CASE STUDY-3

Oil Spill in USA

An oil spill is the release of a liquid petroleum

hydrocarbon into the environment, especially marine areas,

due to human activity.

Oil spill occurs when liquid petroleum is released into

water by vehicles, pipelines or oil tankers. Among these the

accidents and grounding of oil tankers are the chief reasons

for oil spill.

When oil spills and mixes with water it can contaminate

drinking water, kill fish and poison wildlife. Just one quart of

oil may pollute up to 150,000 gallons of water. Oil is harmful

to shellfish, finfish, marine mammals and waterfowl who live

near the spill.

Oil floating on the water contaminate plankton (very

small, swimming or floating plants and animals). When small

fish eat these plankton, they also consume the oil.

When oil gets on a bird’s feathers, the feathers lose

their insulation capability and the bird can’t adjust its body

temperature and dies. Oil may obstruct the germination and

growth of marine plants.

Oil spills are ugly and are expensive to clean up. In

addition, damage to fisheries places a hardship on those who

make their living by fishing.

Less oil is used when people conserve energy by driving

smaller cars, using public transportation or alternatively-

fuelled vehicles or other ways of travel, like walking and

bicycling.

If everyone used less oil, fewer tankers would sail the

seas. This could reduce the risk of oil spills.

WORKSHEET-1

Q.1 Match the following:

Column A Column B

1.NDMA (a) Bihar

2. Deputy Commissioner (b) Brahmaputra

3. Kosi (c) Oil spill

4. Assam (d) Implementation of

government plans

5. Alaska (e) Apex body for

Disaster Manage-

ment in India

Q.2 Fill in the blanks

1. ________ is the apex body which lays down the policies,

plans and guidelines for Disaster Management in India.

2. ______ and _______ are man-made disasters.

3. If you feel the earthquake while driving you should ______

4. ___________ and __________ play a major role during any

kind of disaster.

5. An __________ is the release of a liquid petroleum

hydrocarbon into the environment.

ANWERS OF WORKSHEET-1

Q.1 Match the following

1. e

2. d

3. a

4. b

5. c

Q.2 Fill in the blanks

1. NDMA

2. Wars, riots

3. pullover and stop and stay inside the vehicle

4. Paramilitary force, civil

5. oil spill

SHORT AND LONG QUESTION ANSWERS

A. Answer the following questions briefly:

Q.1. Define disaster.

Ans: A disaster is a sudden, calamitous event that seriously

disrupts the functioning of a community or society and

causes human, material and economic or environmental

losses.

Q.2. What are two major types of disasters?

Ans: Natural and man-made disasters.

Q.3. What are natural disasters?

Ans: Natural disasters are the disasters which are caused by

the forces of nature and are beyond the control of human

beings.

Q.4. What are man-made disasters?

Ans: Man-made disasters are those for which human beings

themselves are responsible.

Q.5. Define disaster management

Ans: Disaster management is a planned steps taken to

minimize the effects of a disaster.

Q.6. What is flood?

Ans: A flood is an abnormal rise of river or any water body

due to heavy rainfall, tsunami, cyclone etc.

Q.7. Define earthquake

Ans: It is the trembling or sudden shaking of ground that

happens when rock masses on the earth’s surface are

abruptly displaced.

Q.8. Name the ministry which coordinates disaster

management activities in India.

Ans: Ministry of Home Affairs.

Q.9. Name the important rivers of Assam.

Ans: (i) Brahmaputra (ii) Barak

Q.10. Which river is known as ‘Sorrow of Bihar’?

Ans: Kosi

Q.11. What was the cause of Nepal’s earthquake of 2015?

Ans: Earthquake of Nepal and India along the Himalayan belt

were caused mainly due to collision of Indian plate and

Eurasian plate.

Q.12. What is an oil spill?

Ans: An oil spill is the release of a liquid petroleum

hydrocarbon into the environment, especially marine areas,

due to human activity.

Q.13. Define planktons

Ans: Planktons are very small, swimming or floating plants

and animals in water.

Q.14. Analyse the impact of oil spill on birds.

Ans: When oil gets on a bird’s feathers, the feathers lose

their insulation capability and the bird can’t adjust its body

temperature and dies.

Q.15. State any two ways through which you can help to

stop oil spill.

Ans: (i) Less oil is used when people conserve energy by

driving smaller cars, using public transportation or

alternatively-fuelled vehicles or other ways of travel, like

walking and bicycling.

(ii) If everyone used less oil, fewer tankers would sail the

seas. This could reduce the risk of oil spills.

B. Answer the following questions in detail:

Q.1. Distinguish between man-made and nature disaster.

Ans:

NATURAL DISASTERS MANMADE DISASTERS

(i) Natural disasters are (i) Man-made disasters

the disasters which are are those for which hum-

caused by the forces of an beings themselves

nature and are beyond are responsible.

the control of human

beings.

(ii) Earthquakes, floods, (ii) Wars, riots, nuclear

landslides, volcanic explosions, industrial

eruptions, etc. are accidents, etc. are some

natural disasters. the man-made disasters.

Q.2. Analyse the need for disaster management.

Ans: (i) Disaster management aims to reduce, or avoid the

potential losses from hazards, assure prompt and

appropriate assistance to victims of disaster, and achieve

rapid and effective recovery.

(ii) Disaster management is an important component of all

the communities. History has shown us that where

communities have been prepared to face disasters, lesser

lives have been lost, less significant damage to the

environment has occurred, and property has been better

conserved.

Q.3. Explain the four phases of disaster management.

Ans: Four phases of disaster management are:

(i) Migration: Its aim is to minimise the effects of disaster

through building codes and zoning; vulnerability analyses;

public education.

(ii) Preparedness: It focuses on understanding how a disaster

might impact the community and how education, outreach

and training can build capacity to respond to and recover

from a disaster.

(iii) Response: The aim of emergency response is to provide

immediate assistance to maintain life, improve health and

support the morale of the affected population. Search and

rescue; emergency relief are important components of

response.

(iv) Recovery: It is fourth phase of disaster management. It

includes actions taken to return to a normal or an even safer

situation following an emergency. Getting financial

assistance, temporary housing, medical care are important

components of recovery phase.

Q.4. Suggest any four ways to minimize the loss occurring

due to floods.

Ans: (i) Avoid building in a floodplain.

(ii) Construct barriers to stop floodwater from entering

your home.

(iii) If a flood is likely in your area, listen to the radio or

television for information.

(iv) Know the difference between a flood watch and

flood warning. A watch means flooding is possible. A

warning means flooding is occurring or will occur soon.

Q.5. State any four action which you will take immediately

after an earthquake.

Ans: (i) Put out all the domestic fires and turn off heaters.

(ii) Turn off electricity, gas and water, if the house is

damaged.

(iii) Leave the house if a fire starts that cannot be put

out at once.

(iv) Move to the nearest shelter or evacuate the area if

this is ordered by the appropriate government agency.

Q.6. Mention some do’s and don’ts to avoid fire accidents.

Ans: Do’s

Use I.S.I. Certified appliances.

Switch off the electric supply of the fire affected areas.

It is safe to play firecrackers in open grounds and open

places.

Don’ts

Don’t use substandard fixtures, appliances.

Never have temporary or naked joints on wiring.

Don’t lay wires under carpet, mats or doorways.

Q.7. Analyse the role of government in Disaster

Management.

Ans: (i) The Central Government supplements the efforts of

the State Government by providing financial and logistic

support.

(ii) The Ministry of Home Affairs is the Nodal Ministry at the

Centre for coordinating disaster management activities for all

natural hazards. National Disaster Management Authority is

the apex body which lays down the policies, plans and

guidelines for Disaster Management to ensure timely and

effective response to disaster.

(iii) The actual day-to-day function of administering relief is

the responsibility of the District Magistrate/ District

Collector/ Deputy Commissioner who exercises coordinating

and supervising powers over all the departments at the

district level.

Q.8. “The effects of floods are diverse and manifolds”.

Explain the statement by taking examples from Assam and

Bihar.

Ans:

(i) Soil erosion and degradation of land and water leads

to damage of the production base, thus adversely

affecting the sustainable agriculture as well as

development.

(ii) Floods also leads to the damage of irrigation

channels. The irrigation channels in the flood prone

areas either damaged or covered with soil.

(iii) Large scale damages are seen on the live-stock and

population. Heavy floods wash away and kill the live-

stocks such as domestic and wild animals

(iv) Every year, Brahmaputra floods the national park,

thus forcing animals to encroach into human

settlements. This leads to man-animal conflict, making

animals vulnerable to poaching and road accidents.

Q.9. “Earthquakes constitute one of the most terrible

natural hazards which often turn into disaster causing

extensive devastation and loss of human lives and their

properties.” Explain the statement by taking examples from

Nepal.

Ans:

The earthquake resulted in a significant loss of standing

crops : wheat, barley and potato (close to harvest in

higher altitude areas) and maize (newly planted in lower

altitude areas).

Earthquake also damaged additional food storage

facilities reducing already limited stocks. Malnutrition

rates in certain areas of Nepal are among the highest in

the world.

Water supplies were severely affected increasing public

health risks including the spread of WASH related

disease.

Key infrastructure – including schools, health facilities,

access roads, temples and heritage sites – were

damaged or destroyed.

Over 1,000 health facilities were destroyed or severely

damaged including primary health care centres, village

health posts and birthing centres.

Q.10. Analyse the impacts of oil spills.

Ans:

(i) When oil spills and mixes with water it can

contaminate drinking water, kill fish and poison

wildlife

(ii) Oil is harmful to shellfish, finfish, marine mammals

and waterfowl who live near the spill.

(iii) Oil floating on the water contaminate plankton

(very small, swimming or floating plants and

animals). When small fish eat these plankton, they

also consume the oil.

(iv) When oil gets on a bird’s feathers, the feathers lose

their insulation capability and the bird can’t adjust

its body temperature and dies