INDEX

Notes for Disaster Mitigation and Management (latest syllabus AY-2021-2022)

Disaster Management & Mitigation - UNIT-I

Disaster Management & Mitigation - UNIT-II

Disaster Management & Mitigation - UNIT-III

Disaster Management & Mitigation - UNIT-IV

Disaster Management & Mitigation - UNIT-V

IMPORTANT ABBREVIATIONS

Types of hydrometeorological disasters and geographical based disasters

Ways in which remote sensing and GIS help in disaster mitigation and management

Bhopal gas tragedy as a chemical industrial disaster

Differences between human induced and human made disasters

Natural Disasters

Crowdsourcing and ICT in disaster management

Instruments used to predict occurrence of natural disasters

Landslides and use of remote sensing to predict their occurrence

APPLICATIONS OF REMOTE SENSING & GIS IN DISASTER MANAGEMENT - 1

List of Indian Remote Sensing Satellites

Disaster Management Information System (DMIS)

Traffic accidents becoming a hazard - An example (Case study)

Effects of a major power breakdown

Risk and Vulnerability in the context of disaster management

Vulnerability of India to disasters

Classification of disasters

Desertification

Drought

Avalanche

Landslides

DRR - Disaster Risk Reduction

Definition of Disaster

International Decade for Natural Disaster Reduction - IDNDR

Floods in India

What is disaster management & Disaster Management Cycle

Tsunami

Disaster Management Continuum

National Disaster Management Structure

Avalanche

Cyclones

Natural Disasters - Hydrometeorological based disasters

Introduction to Disaster Management

Geospatial technologies currently used for Disaster Mitigation and Management

The following questions for the course on Disaster management and mitigation have actually appeared on previous final examination question papers!

IMPORTANT QUESTIONS IN DISASTER MANAGEMENT & MANAGEMENT

Important material for disaster management (Overall in brief - few topics in the syllabus might not be covered)

Geo-spatial technologies in disaster management

Major power breakdowns as a disaster

Warning and forecasting methods in disaster management

Vulnerability and Risk in disaster management

GIS in disaster management

What is GIS

What is Remote Sensing

Notes, and website links - REFERENCES

Man-made and Human-Induced disasters in detail

Very useful website (blog)

Disaster Mitigation

Names given to cyclones in different parts of the world

Landslide Vs Avalanche - The difference

Methods to measure an earthquake

Characteristics of natural disasters

Man-made disasters and Human-induced disasters

Natural Disasters - Tsunami: Causes, Effects and response

Warning and forecasting of Earthquakes

Warning and forecasting of Tsunami

Warning and early forecasting of droughts

Forecasting and warning of landslides

Warning & forecasting of floods

Ways in which remote sensing and GIS help in disaster mitigation and management

Geographic Information System (GIS) is a computer based application of technology involving spatial and attributes information to act as a decision support tool. It keeps information in different layers and generates various combinations pertaining to the requirement of the decision making. GIS has emerged as an effective tool in management of disasters since, geo-spatial data and socio-economic information need to be amalgamated for the better decision making in handling a disaster or to plan for tackling a disaster in a better way. GIS could be utilized by the different line departments and agencies who are stakeholders in the disaster management process. Some basic hardware like computer system, printer, network systems, along with GIS software are required to set up the GIS in any organisation.
The prime objectives of developing the GIS database are to help disaster managers at local and regional levels for:

1. Pre-disaster planning and preparedness
2. Prediction and early warning
3. Damage assessment and relief management

GIS combines layers of information on various themes to enable the managers to take the most appropriate decisions under the given circumstances. For disaster management, a GIS database could be a useful managerial tool for the reasons listed below:

1. Disaster Managers could generate maps both at micro and macro level indicating vulnerability to different extents under different threat perceptions.
2. Locations likely to remain unaffected or remain comparatively safe could be identified.
3. Alternate routes to shelters, camps, and important locations in the event of disruption of normal surface communication can be planned
4. Smooth rescue and evacuation operations could be properly planned.
5. Rehabilitation and post-disaster reconstruction works could be properly organized.
6. Locations suitable for construction of shelters, godowns, housing colonies, etc. can be scientifically identified.
7. Areas where no construction should be taken up or existing habitations require relocation, could be identified.

Department of Space (DOS, India) has embarked upon the Disaster Management Support to extend the benefits of the aerospace technology for the resolution of disaster management in the country. The Decision Support Centre (DSC) established at National Remote Sensing Centre (NRSC) is the single window delivery point for aerial and space enabled inputs together with other important data layers for its use in disaster management of pre-disaster, during-disaster and post-disaster phases. The natural disasters being addressed are  Flood, Cyclone, Agricultural Drought, Forest Fire, Earthquake and Landslide. Depending upon the satellite pass, cameras are tilted and data is acquired and analysed. The information is monitored on a regular basis for damage assessment. DSC has provision to mobilize aircraft equipped with Synthetic Aperture Radar (SAR), Air-borne Laser Terrain Mapping unit (ALTM) and High Resolution Digital Camera for obtaining aerial data. DSC is working on space inputs for long-term disaster mitigation and rehabilitation. Use of remote sensing data for various natural disasters is discussed below:

FLOOD: To keep watch on the flood situation in the country through hydrological and meteorological information from various sources, mapping & monitoring of major flood/cyclones with the satellite data from optical and microwave satellites, Generation of flood maps showing flood. The most flood-prone areas in India are the Brahmaputra, Ganga and Meghana River basins in the Indo-Gangetic-Brahmaputra plains in North and Northeast India. ISRO/DOS is playing a vital role in supporting the flood management activities, by providing space as well as aerial remote sensing based services and products. Using satellite data from Indian Remote Sensing Satellite (IRS) System and from foreign satellites, the impact of floods in the country is assessed. The services provided in this context include:

1. Near Real Time Flood Mapping and Monitoring
2. Flood Damage Assessment
3. Flood Hazard Zone Mapping
4. River Bank Erosion Mapping and
5. Mapping changes in the river course

CYCLONES: Cyclones are wind-systems of relatively low pressure which spiral inwards towards a centre in the lowest atmospheric levels and cause immense destruction and loss of life when they strike coastal areas. Satellite communications provide an effective mechanism for real-time dissemination of information and early warning besides establishing communication link after cyclone hit. Earth observation satellites enable continuous monitoring of atmospheric as well as surface parameters. Information acquired by satellite remote sensing covers wide area, periodicity and spectral characteristics and especially in the easiness to compare the data before and after a disaster.

DROUGHT: Agricultural drought assessment using space technology inputs has been operational in India since 1989, through a project 'National Agricultural Drought Assessment and Monitoring System (NADAMS)'. NADAMS provides near real-time information on prevalence, severity level and persistence of agricultural drought at regional and local levels through remote sensing.

FOREST FIRES: Indian Remote Sensing Satellite images were acquired and processed to monitor the forest fire incidence. The Decision Support Center (DSC) is established at National Remote Sensing Centre (NRSC) as part of Disaster Management Support Programme of Department of Space (DOS), for working towards effective management of disasters in India. A comprehensive Indian Forest Fire Response and Assessment System (INFFRAS) is invoked under DSC activities of NRSC, which integrates multi-sensor satellite data and ground data through spatially and temporally explicit GIS analysis frame work. This system provides information on:

1. Fire alerts
2. Fire progression
3. Burnt area assessment and
4. Forest fire mitigation plans

Bhopal gas tragedy as a chemical industrial disaster

On the night of December 2, 1984, the chemical, methyl isocyanate (MIC), spilled out from Union Carbide India Ltd’s (UCIL’s) pesticide factory turned the city into a vast gas chamber. People ran on the streets, vomiting and dying. This was India’s first (and so far, the only) major industrial disaster. This was a chemical industrial disaster and the Government had no clue how to respond in this case. The US-based multinational company, Union Carbide Corporation (UCC), which owned the plant through its subsidiary UCIL(Union Carbide India Limited), failed to deal with the human tragedy.

Bhopal was struck by two tragedies: the one that happened immediately, and the other that unfolded in the years that followed.

The problem was nobody knew much about the toxin or its antidote. Within weeks of the accident many claimed that people were suffering from common ailments of the poor, such as tuberculosis and anaemia. However, till date nobody knows the health impacts of MIC and how to treat patients exposed to the gas. The children born after the disaster are also its victims because of exposure to the deadly gas while they were in their mothers’ wombs.
Additionally, chemical wastes remain dumped in and around the premises of UCIL factory, contaminating the water that people drink.
Union Carbide used trade secrecy as a prerogative to withhold information on the exact composition of the leaked gases. MIC, when reacts with water at high temperatures and releases as many as 300 highly toxic chemicals.
In the first few days, there was evidence that people could be suffering from cyanide poisoning—intravenous injections of sodium thiosulphate, an antidote, imagewas found to be working on the patients. But soon, it was discontinued.

In 1989, UCC paid some US $470 million (worth Rs 750 crore that year) as compensation for the disaster. This was one-seventh of the original demand from the Indian government. However, all civil and criminal cases against the company were terminated. Later, it was realised that many more were suffering from exposure to the poisonous gas. So, when the case was decided, compensation was doled out to virtually the entire city. The final settlement was less than Rs 15,000 per victim.

Bhopal disaster 2.0

The factory used to manufacture three pesticides: carbaryl (trade name Sevin), aldicarb (trade name Temik) and a formulation of carbaryl and gamma-hexachlorocyclohexane (g-HCH), sold under the trade name, Sevidol. For 15 years till the disaster, it dumped process wastes, by-products, solvents, sub-standard products, wastes from machinery and polluted water at dump sites inside and outside the plant. Another 350 tonnes of waste has been kept in a leaking shed at the site. These wastes are still lying at the site, polluting soil and groundwater. This second legacy—Bhopal Disaster 2.0—now threatens even a larger number of people than the first one. Many of the chemicals degrade slowly and are likely to remain in the environment for hundreds of years. They will keep spreading unless they are taken out and the site is decontaminated.

Most studies found groundwater surrounding the UCIL site to be contaminated with chlorinated benzenes and HCH isomers. Carbaryl, aldicarb, carbon tetrachloride and chloroform were also detected in some studies. All these can be linked to the wastes dumped by UCIL plant.

The Union government asked Dow to deposit Rs 100 crore for environmental remediation. Dow has continued frantic lobbying to get the Indian government to withdraw its application.

The disaster had impacts far beyond the boundary of the ill-fated city and its people. It made a difference worldwide to the way that chemical and hazardous waste management was reinforced; workers’ safety precautions mandated; and legislation for environmental management strengthened. Perhaps, this is why we have not seen another Bhopal-like disaster in the past 30 years.

After 30 years, the government of India is still struggling to establish the liability of UCIL, its parent company UCC and its buyer, Dow Chemical.

Differences between human induced and human made disasters

Differences between Human induced and Human made disasters
The primary difference between human induced disasters is that human induced disasters happen unintentionally while human made disasters are intentional. This difference is illustrated below with the help of an example.

Love canal disaster can be termed as a human induced disaster while pollution of the air affecting the health of the population can be termed as a human made disaster.

The love canal tragedy occurred when the toxic chemicals buried underground by the hooker chemical company contaminated the groundwater. The company responsible for this tragedy did not do it on purpose. Hence this disaster can be classified as a human induced disaster.

The increased usage of automobiles in urban areas, has resulted in a very high concentration of pollutants. These pollutants pose a great health risk to new born babies and the elderly. Some of the consequences of this are lung infections, reduced immunity and lack of concentration. Growing population and urbanisation has made this a human-made disaster as this is being done intentionally.

Effects of a major power breakdown

Electricity plays an essential role in our lives. We require electricity for almost all our daily activities at work or home. Failure of electricity or power breakdown paralyses our lives. Power breakdown has been experienced by everyone. Failure of companies to supply electricity to a large area or city for an extended duration is termed as a major power breakdown. The various effects of a major power breakdown are listed below:

1. Inability to use any appliance (at home or work) that depends on electric power. Example: Iron box, Grinding machine, Fans, Lights, AC's, etc., at home and Computers, Copying machines, AC's, Lights, etc., at work
2. Farmers and residents will be unable to use electric pumps to draw water from wells
3. Traffic lights will be non-operational in the affected area causing chaos and leading to traffic accidents
4. Health services will be interrupted and all medical equipment depending on electric power will be non-operational leading to trauma and possible loss of life.
5. A major power breakdown will have a severe negative effect on the socioeconomic fabric of the society
6. Major power breakdowns cause severe financial losses to the Government and private industries.

Risk and Vulnerability in the context of disaster management

RISK is generally defined as the expected impact caused by a particular phenomenon. It combines the likelihood or possibility of a disaster happening and the  negative effects that result if the disaster occurs. Risk is hazard multiplied by vulnerability less the capacity of the population to cope. Risk is defined as the probability of a damaging event or circumstance.

Vulnerability is the extent to which an individual, community, sub group, structure, service or geographical area is likely to be damaged by the impact of a particular disaster. The factors that influence vulnerability include physical, economical, social, political, technical, idealogical, cultural, ecological, institutional and organisational. Vulnerability is the potential for experiencing loss.

Vulnerability is comprised of three elements:

1. Exposure: It is the degree of risk of an event experienced in daily life from the probability of a hazard to actual occurrences of events of all sizes.
2. Resilience: It is the ability to recover, ranging in degree from simply achieving stability at any level of functioning to recovering the full range of resources and positive momentum that existed prior to the event
3. Resistance: It is the ability to withstand the impacts and continue to function. 

Vulnerability of India to disasters

VULNERABILITY PROFILE OF INDIA

India is vulnerable in varying degrees to a number of disasters.

1. More than 55% of the landmass is prone to Earthquakes of moderate to very high intensity
2. More than 10% of its landmass is prone to floods and river erosion
3. More than half of its long coastline of 7500 kms is prone to cyclones and tsunamis
4. More than 65% of its cultivable area is vulnerable to droughts and its hilly areas are at risk from landslides and avalanches.
5. India is also vulnerable to CBRN (Chemical, Biological, Radiological & Nuclear) emergencies and other man-made disasters
6. Disaster risks in India are further compounded by vulnerabilities related to changing demographics & socio-economic conditions like unplanned urbanization, development in high risk zones, environmental degradation, climate change, geological hazards, epidemics (SARS) and pandemics (AIDS)

Creation of a vulnerability atlas containing a combination of local hazard intensity & vulnerability of existing house types to formulate pro-active policies to face threat of natural hazards.

International research institute (IRI) for climate prediction provides a seasonal climate forecast. This information is provided from a variety of climate prediction tools. For example:

1. Dynamic models of the atmosphere
2. Statistical models of climate variability related to sea surface temperature variability and
3. knowledge of current state of climate system.

Classification of disasters

Classification of disasters
Disasters are generally classified into natural and technological which is again classified as listed below.
Natural Disasters are classified into:
    -Geophysical disaster
    -Meteorological disaster
    -Hydrological disaster
    -Climatological disaster
    -Biological disaster and
    -Extraterrestrial disaster
Technological disasters are classified into:
    -Industrial accident
    -Transport accident and
    -Miscellaneous accident

A geophysical disaster originates from solid earth. It is used interchangeably with the term  geological hazard. Earthquakes, mass movements and volcanic activity fall under this category.

Meteorological disasters are short lived and caused by micro to meso-scale extreme weather and atmospheric conditions that last from minutes to days. Extreme temperature, fog and storm are examples of this type of disaster.

Hydrological disasters are caused by the occurrence, movement, and distribution of surface and subsurface freshwater and saltwater. Flood, landslide, wave action are examples of this type of disaster.

Climatological disasters are caused by long-lived, meso to macro-scale atmospheric processes ranging from intra-seasonal to multi-decadal climate variability. Drought, glacial-lake outburst and wildfires are examples of this type of disaster.

Biological hazards are caused by  the exposure to living organisms and their toxic substances (e.g. venom, mold) or vector-borne diseases that they may carry. Examples are venomous wildlife and insects, poisonous plants, and mosquitoes carrying disease-causing agents such as parasites, bacteria, or viruses (e.g. malaria). Epidemic, insect infestation and animal accident are examples of this type of disaster.

An Extraterrestrial hazard is caused by asteroids, meteoroids, and comets as they pass near-earth, enter the Earth’s atmosphere, and/or strike the Earth, and by changes in interplanetary conditions that effect the Earth’s magnetosphere, ionosphere, and thermosphere. Impact of celestial bodies and space weather are examples of this type of disaster.

Examples of industrial accidents are chemical spill, collapse, explosion, fire, gas leak, poisoning, radiation, etc.

Examples of transport accidents include disasters involving transport of hazardous material via air, water, rail or road.

Miscellaneous disasters under technological disasters include collapse, explosion, fire and other related accidents

Sub-types under:
    -    Earthquakes are ground shaking and tsunami
    -    Volcanic activity are ash fall, lahar, pyroglastic flow, lava flow and liquefaction
    -    Storms are Extra-tropical, Tropical and convective. Convective storms are
        further     classified into:   
                    -Derecho
                    -Hail
                    -Lightening/Thunderstorm
                    -Rain
                    -Tornado
                    -Sand/Dust storm
                     -Winter storm/Blizzard
                    -Storm/Surge
                    -Wind
Extreme temperature is classified into:
    -    Cold wave
    -    Heat wave and
    -    severe winter conditions (this is again classified into snow/ice and          
         frost/freeze)
    -    Fog
Under hydrological disaster
    floods are classified into:
    -    Coastal flood
    -    Riverine flood
    -    Flash flood and
    -    Ice jam flood
    Example of a landslide is debris, mud flow, rock fall or avalanche (snow)
Examples of wave action are rogue waves or seiche

Examples of extraterrestrial disasters are Airburst, Energetic particles, Geomagnetic storm and shockwaves

Desertification

Desertification is a type of land degradation in which a relatively dry land region becomes increasingly arid, typically losing its bodies of water as well as vegetation and wildlife. It is caused by a variety of factors, such as climate change and human activities.
Desertification is a significant global ecological and environmental problem. It is defined as "the process of
fertile land transforming into desert typically as a result of deforestation, drought or improper/inappropriate
agriculture"
The immediate cause is the removal of most vegetation. This is driven by a number of factors, alone or in combination, such as drought, climatic shifts, tillage for agriculture, overgrazing and deforestation for fuel or construction materials. Vegetation plays a major role in determining the biological composition of the soil.
Twenty- five per cent of India's total land is undergoing desertification while 32 per cent is facing degradation that has affected its productivity, critically affecting the livelihood and food security of millions across the country. Rajasthan accounts for the most desertified land (23 Mha), followed by Gujarat, Maharashtra
and Jammu and Kashmir(13 Mha each) and Orissa and Andhra Pradesh (5 Mha each) 68 per cent of the country is prone to drought, and this will be further heightened because of the impact of climate change,
particularly in dry lands.
The prime causes of desertification are:
-Overgrazing
-over-exploitation
-deforestation
-inappropriate irrigation
-population pressure
-urbanisation
-poverty and
-inequitable sharing of resources.

Drought

A drought is a situation caused due to an extended period of rain deficiency. Droughts can affect large countries or a small village. A drought normally occurs when a region receives below average rainfall. It can have substantial impact on the ecosystem and agriculture of the affected region. Droughts can persist for a long period of time, even a short intense drought can cause significant damage and harm to the local communities. An area is declared by the government as drought affected when rainfall is less than 25% of the average annual rainfall for that area. It is declared as severely drought affected when deviation of rainfall from normal is more than 50%. Droughts are of three types:
1. Meteorological drought is when rainfall is 25% less than average
2. Agricultural drought when rainfall is not conducive to the growth of monsoon crop
3. Hydrological drought when water bodies dry up in surface and in aquifers under the surface.

In India, the western parts of Odhisha, Madhya Pradesh, Jharkhand, Chhattisgarh, Western Rajasthan, regions of Andhra Pradesh bordering Odhisha, Madhya Pradesh, Parts of Maharashtra and western West Bengal are prone to recurrent droughts.

Drought is a slow onset disaster; hence it is predictable. A few tools to predict droughts are: satellite imageries, rainfall data, increase in cost of food in local market, migration of able bodied men and overlay of GIS map and grid population map. Government and Non government agencies use such data to plan appropriate response to mitigate the effects of drought.

Avalanche

Avalanche is a rapid movement of snow down a slope triggered either naturally or by human activity. This occurs typically in mountain terrain. Avalanches are divided into four classes:
1. Dry powder avalanches
2. Wet new snow avalanches
3. Snow slabs or Wind slabs and
4. Wet old snow avalanches.

Avalanches are river like speedy flow of snow or ice descending from the mountain tops. Avalanches are very damaging and cause huge loss to life and property. 

In Himalayas, avalanches are common in Drass, Pir Panijat, Lahaul-Spiti and Badrinath areas. As per Snow and Avalanche Study Establishment (SASE), of Defence Research and Development Organisation (DRDO), on an average around 30 people are killed every year due to this disaster in various zones of the Himalayas. Beside killing people, avalanches also damage the roads and others properties and settlements falling in its way. 

Area Prone to Avalanches

Avalanches are common in Himalayan region above 3500m elevation.

Very frequent on slopes of 30-45°.

Convex slopes more prone to this disaster.

North facing slope have avalanches in winter and south facing slopes during spring.

Slopes covered with grass more prone to this hazard.

Landslides

Landslides
Landslides are simply defined as the mass movement of rock, debris or earth down a slope and have come to include a broad range of motions whereby falling, sliding and flowing under the influence of gravity dislodges earth material. They often take place in conjunction with earthquakes, floods and volcanoes. At times, prolonged rainfall causing heavy block the flow or river for quite some time. The formation of river blocks can cause havoc to the settlements downstream on it's bursting. In the hilly terrain of India including the Himalayas, landslides have been a major and widely spread natural disaster the often strike life and property and occupy a position of major concern.
The two regions most vulnerable to landslides are the Himalayas and the Western Ghats. The Himalayas mountain belt comprise of tectonically unstable younger geological formations subjected to severe seismic activity. The Western Ghats and nilgiris are geologically stable but have uplifted plateau margins influenced by neo- tectonic activity. Compared to Western Ghats region, the slides in the Himalayas region are huge and massive and in most cases the overburden along with the underlying lithology is displaced during sliding particularly due to the seismic factor.

Incidences of landslides in India

Himalayas                                                                      - High to very high
North-eastern Hills                                                         - High
Western Ghats and the Nilgiris                                        - Moderate to high
Vindhayachal                                                                  - Low

Landslides Zonation Mapping is a modern method to identify landslides prone areas and has been in use in India since 1980s
The major parameters that call for evaluation are as follows:
-Slope-Magnitude, length and Direction
-Soil thickness
-Relative relief
-Land use
-Drainage-pattern and density
-Landslide affected population

Causes of Landslides 
Landslides can be caused by
1. Poor ground conditions
2. Geomorphic phenomena
3. Natural physical forces
4. Quite often due to heavy spells of rainfall coupled with impeded drainage.

Ground causes of landslides:
1.Weak, sensitivity, or weathered materials
2.Adverse ground structure (joints, fissures etc.)
3.Physical property variation (permeability, plasticity etc)

Morphological Causes
-Ground uplift (volcanic, tectonic etc)
-Erosion (wind, water)
-Scour
-Deposition loading in the slope crest.
-Vegetation removal (by forest fire, drought etc)

Physical Causes
-Prolonged precipitation
-Rapid draw-down
-Earthquake
-Volcanic eruption
-Thawing
-Shrink and swell
-Artesian pressure

Man- made Causes
-Excavation (particularly at the toe of slope)
-Loading of slope crest
-Draw -down (of reservoir)
-Deforestation
-Irrigation
-Mining
-Artificial vibrations
-Water impoundment and leakage from utilities

DRR - Disaster Risk Reduction

The concept and practice of reducing disaster risks through systematic efforts to analyse and manage the causal factors of disasters, including through 

- reduced exposure to hazards, 

-lessened vulnerability of people and property, 

-wise management of land and the environment, and 

-improved preparedness for adverse events. 

A comprehensive approach to reduce disaster risks is set out in the United Nations-endorsed Hyogo Framework for Action, adopted in 2005, whose expected outcome is “The substantial reduction of disaster losses, in lives and the social, economic and environmental assets of communities and countries.” 

The International Strategy for Disaster Reduction (ISDR) system provides a vehicle for cooperation among Governments, organisations and civil society actors to assist in the implementation of the Framework. The terms “disaster reduction” (DR) and the term “disaster risk reduction” (DRR) are synonymous. 

DRR provides a better recognition of the ongoing nature of disaster risks and the ongoing potential to reduce these risks.

Definition of Disaster

According to UNISDR (United Nations International Strategy for Disaster Reduction), a disaster is defined as a serious disruption of the functioning of a community or a society involving widespread human, material, economic or environmental losses and impacts, which exceeds the ability of the affected community or society to cope using its own resources.

According to WHO, "A disaster is an event that causes damage, economic disruption, loss of human life and deterioration of human health and the health of societies on a scale sufficient to warrant an extraordinary response from outside the affected community or area."

International Decade for Natural Disaster Reduction - IDNDR

The United Nations General Assembly designated the 1990s as the International Decade for Natural Disaster Reduction (IDNDR).

Its basic objective was to decrease the loss of life, property destruction and social and economic disruption caused by natural disasters, such as earthquakes, tsunamis, floods, landslides, volcanic eruptions, droughts, locust infestations, and other disasters of natural origin.

An International Decade for Natural Disaster Reduction, beginning on 1 January 1990, was launched by the United Nations, following the adoption of Resolution 44/236 (22 December 1989). The decade was intended to reduce, through concerted international action, especially in developing countries, loss of life, poverty damage and social and economic disruption caused by natural disasters. To support the activities of the decade, a Secretariat was established at the United Nations Office in Geneva, in close association with UNDRO.

Floods in India

The Indian subcontinent is highly vulnerable to a number of natural disasters.
Droughts, Floods, Cyclones and Earthquakes are natural disasters in the
country though Landslides, Avalanches and bush fire also occur in most of the states of the Himalayan region.

Due to unique and widely varying geographical and geological conditions of the
India, virtually all types of natural disasters take place with various intensities
and in different regions.

Floods occur when large volume of water from heavy rainfall and/or river overflow canals and is not able to drain quickly through normal channels. Floods are the most frequent and widespread natural disasters resulting in death, destruction, degradation and displacement. Whether sudden onset or slow development, floods take long to subside and they leave prolonged damage.

India is the second most flood affected country where flood is a common national disaster especially during the later part of the monsoon period. Severe floods occur almost every year in one part of the country or the other causing loss of life, large scale damage to property and untold misery to millions of people.

Floods are estimated to affect 6.7 million hectares of land annually. The effects of flood on the affected population are:
1. inundation marooning,
2. drowning,
3. loss of habitat, roads, communications,
4. destruction of crops,
5. industrial shutdown,
6. diarrohea diseases, respiratory infections etc.
Most of the affected population is among the poorer sections.

In India the most affected states due to floods are Bihar, Assam, Uttar Pradesh, the states in the northeast, Orrisa & West Bengal. Floods cause serious damage in states like Andhra Pradesh, Gujarat, Haryana, Punjab, Rajasthan & Tamil Nadu.

To control floods:
- Rashtriya Barh Ayog was established in 1976 and
-Task force on flood management & soil erosion was setup in 2004

Primary responsibility of flood control rests with with state Governments.

Structural measures for flood management include:
-Flood embankments
-Dams & Reservoirs
-Natural detention basins
-Channel improvement
-Drainage improvement
-Diversion of flood waters
-Afforestation
-Catchment Area Treatment
-Anti-erosion works

Non-structural measures include:
-Flood plain zoning & flood proofing
-Flood preparedness & community level awareness
-Flood forecasting & early warning system
-Afforestation
-Public relief and flood insurance

Increased vulnerability due to floods occurs due to:
-Indiscriminate encroachment
-Increasing economic and developmental activity in flood plains
-Lack of regulations
-Inadequate maintenance
-Inadequate drainage
-Lack of disaster preparedness

Flood management strategies
Flood forecasting and warning steps involve:
-Data collection of hydrological data including river water level and river discharge
-Data collection of hydrometeorological data including rainfall and other precipitation like hail, snow, etc..
-Wireless. telephone, fax, satellite, telegraph, etc
-Correlation, mathematical models
-Civil authorities, Press, AIR, Doordarshan, other users, local representatives

-Flood plain zoning is an important non-structural resource. It regulates land use in flood plains to restrict damage by floods. It involves demarcation by zones in flood plains compatible with flood risks involved.
-The floor of lowest storey of buildings should be raised above the normal minimum flood level of adjoining land.
-People living in flood banks should be shifted to other places.
-Road side drains should be provided to rain drain water from urban areas.

What is disaster management

Tsunami

Disaster Management Continuum

National Disaster Management Structure

Avalanche

Avalanche is a rapid movement of snow down a slope triggered either naturally or by human activity. This occurs typically in mountain terrain. Avalanches are divided into four classes:
1. Dry powder avalanches
2. Wet new snow avalanches
3. Snow slabs or Wind slabs and
4. Wet old snow avalanches.

Cyclones

Spiral movement of winds towards a low pressure centre is called a cyclone. Storms associated with low pressure and rising winds are called cyclonic storms. The movement of wind in a cyclone is counter-clockwise in the northern hemisphere and clockwise in the southern hemisphere.
if the wind speed exceeds 73 miles/hr, then it is called a cyclone
if the wind speed is less than 39 miles/hr then it is called a tropical depression and if the wind speed lies between 39 and 73 miles/hr it is called a storm.

control measures of a cyclone:
1. meteorological information should be given to people as soon as possible.
2. Development activities should be minimised along the frequently affected areas.
3. Modified construction techniques should be adopted to suit buildings in frequently affected areas.

Cyclone is a type of rotating storm that occurs over the seas and oceans near the tropic. A tropical cyclone is a storm system characterized by a large low pressure centre and numerous thunderstorms that produce strong winds and heavy rains. India has a long coastline and the second highest number of people in the world exposed to tropical cyclones. Cyclones strike India in May-June and October-November coinciding with the onset and retreat of monsoon. Coastal Andhra Pradesh, Odhisha, Tamil Nadu and Sunderbans of West Bengal are the major cyclone prone areas of India.

The Odhisha Super cyclone in october 1999 was one of the worst cyclones with wind velocities as high as 350 kmph. Cyclones are generally associated with sea surges, when sea level rises upto 7m. Cyclones are associated with heavy rains. The following factors lead to formation of cyclones:
1. Location and temperature are vital for the formation of cyclones
2. The location must be 5 to 15 degrees latitude on either side of the equator over oceans or seas.
3. The surface temperature of seas or oceans must be more than 26.5 C or above
4. Depression with convection current starts to gather clouds.

Cyclones are easy to predict. The Indian Meteorological Department (IMD) continuously monitors for any low pressure developing in the atmosphere above the ocean using radar. Advanced technology is used to predict the intensity of the cyclonic storm and the coastal area to be hit by any potential cyclone. The large belt along the east coast of India is prone to cyclones and the west coast is also prone to cyclones.

Natural Disasters - Hydrometeorological based disasters

Tropical cyclones:
A tropical cyclone is a rapidly rotating storm system characterized by a low-pressure center, strong winds, and a spiral arrangement of thunderstorms that produce heavy rain.
It is known by different names in different parts of the world.
Tropical cyclones have a geographic origin. They form mostly over tropical seas .They are called cyclones as they have winds blowing counterclockwise in the northern hemisphere and clockwise in the southern hemisphere. The opposite direction of winds is due to the "coriolis effect"
Tropical cyclones typically form over large bodies of relatively warm water. They derive their energy through the evaporation of water from the ocean surface. This water vapour condenses as clouds and falls on Earth as rain when it gets saturated.
Cyclones generate high waves, storm surge and very strong winds. Coastal regions are particularly vulnerable to damage from a cyclone. Heavy rains cause flooding inland while storm surges can cause coastal flooding.
The effect of cyclones on human population is devastating. It has caused loss of life and property since time immemorial.
Tropical cyclones are areas of low pressure.The environment near the center of tropical cyclones is warmer than the surroundings and is called as "warm core". The near-surface wind field of a tropical cyclone is characterised by air rotating rapidly around a centre of circulation while also flowing radially inwards. As air flows radially inward, it begins to rotate cyclonically  in order to conserve angular momentum. Towards the centre, the air begins to rise . Wind speeds are low at the centre and begin to increase rapidly moving outwards. The wind speeds decrease gradually with increasing radii.
There are six Regional Specialized Meteorological Centers (RSMCs) worldwide. These organizations are designated by the World Meteorological Organization and are responsible for tracking and issuing bulletins, warnings, and advisories about tropical cyclones in their designated areas of responsibility. In addition, there are six Tropical Cyclone Warning Centers (TCWCs) that provide information to smaller regions
Worldwide, tropical cyclone activity peaks in late summer, when the difference between temperatures aloft and sea surface temperatures is the greatest. However, each particular basin has its own seasonal patterns. On a worldwide scale, May is the least active month, while September is the most active month. November is the only month in which all the tropical cyclone basins are active.
Most tropical cyclones form in a worldwide band of thunderstorm activity near the equator
The 1990 Andhra Pradesh cyclone or the 1990 Machilipatnam Cyclone was the worst disaster to affect Southern India since the 1977 Andhra Pradesh cyclone. It was first noted as a depression on May 4, 1990. It rapidly intensified into a super cyclonic storm (IMD scale, code named BOB 01) on May 8th. It was given a "category 4" storm on the saffir-simpson scale. The highest wind speeds recorded were greater than 200 kmph.
The storm resulted in the death of nearly 1000 people, 1 lakh animals and estimated samage to crops exceeding 600 million USD.
Cyclonic Storm Nilam  (IMD designation: BOB 02) was the deadliest tropical cyclone to directly affect South India since Cyclone Jal in 2010. Originating from an area of low pressure over the Bay of Bengal on October 28, the system began as a weak depression. northeast of Trincomalee, Sri Lanka. Over the following few days, the depression gradually intensified into a deep depression, and subsequently a Cyclonic Storm by October 30. It made landfall near Mahabalipuram on October 31 as a strong Cyclonic Storm with peak winds of 85 km/h.  In Chennai's Marina Beach, strong winds pushed piles of sand ashore and seawater reached nearly a 100 m (330 ft) inland. Schools and colleges in the city remained closed for more than three days.
More than 3000 people were evacuated around Mahabalipuram in the wake of the storm. Schools and colleges in Chennai declared holidays until November 1 as 282 schools had been converted into relief centers. Government offices and private organisations closed their operations early to ease traffic congestion. Cyclone shelters had been arranged in Nagapattinam and Cuddalore districts. Mahabalipuram faced power outages and several trees were uprooted and huts were damaged. While damages to property were considerable, human casualties were very few 

Search for tropical cyclones in google / wikipedia
List of cyclones in India (Phalin, etc)

Floods:



Droughts:

Introduction to Disaster Management

A disaster is a serious disruption of the functioning of a community or a society involving widespread human, material, economic or environmental losses and impacts, which exceeds the ability of the affected community or society to cope using its own resources.

Developing countries suffer the greatest costs when a disaster strikes.
Hazards are broadly divided into natural or human-made disasters.

A Natural Hazard is a natural process or phenomenon that may cause loss of life, injury or other health impacts, property damage, loss of livelihoods and services, social and economic disruption, or environmental damage. Natural disasters like earthquakes, landslides, volcanic eruptions, floods, hurricanes, tornadoes, blizzards, tsunamis, and cyclones are all natural hazards that kill thousands of people, destroy habitat and property each year.However, the rapid growth of the world's population and its increased concentration often in hazardous environments has escalated both the frequency and severity of disasters. With the tropical climate and unstable land forms, coupled with deforestation, unplanned growth proliferation, non-engineered constructions make the disaster-prone areas more vulnerable, tardy communication, poor or no budgetary allocation for disaster prevention, developing countries suffer more or less chronically by natural disasters. Asia tops the list of casualties caused by natural hazards.

Human-Induced disasters are the consequence of technological hazards. Examples include stampedes, fires, transport accidents, industrial accidents, oil spills and nuclear explosions/radiation. War and deliberate attacks may also be put in this category.

Man-made hazards are events that have not happened, for instance terrorism. Man-made disasters are examples of specific cases where man-made hazards have become reality in an event.

The United Nations General Assembly designated the 1990s as the International Decade for Natural Disaster Reduction (IDNDR).

Its basic objective was to decrease the loss of life, property destruction and social and economic disruption caused by natural disasters, such as earthquakes, tsunamis, floods, landslides, volcanic eruptions, droughts, locust infestations, and other disasters of natural origin.

An International Decade for Natural Disaster Reduction, beginning on 1 January 1990, was launched by the United Nations, following the adoption of Resolution on 22 December 1989. The decade was intended to reduce, through concerted international action, especially in developing countries, loss of life, poverty damage and social and economic disruption caused by natural disasters. To support the activities of the decade, a Secretariat was established at the United Nations Office in Geneva, in close association with UNDRO.

An increase in global industrial activity coupled with population growth and increased fossil fuel consumption has led to the following problems:
-Destruction og green lungs of the earth
-Increased agricultural activity
-Use of toxic pesticides
-Increased green house gases in the atmosphere
-Pollution of air, water and soil
-Acid rain
-Creation of Ozone hole
-Global warming and
-Climate change

There is an increasing trend in the frequency and intensity of both natural & man made disasters. Thic can be attributed to:
-Population explosion
-Rapid industrialization
-Urbanization
-Global warming and
-Environmental pollution