Heat Waves

HEAT WAVES

• Heat wave is defined as a period of excessively hot weather coupled with excessive humidity.
• A heat wave occurs when there are a number of consecutive days with high temperature that the body cannot tolerate
• A a result of heat wave animals and plants suffer from 'heat stress'.
• Human beings suffer from sunstroke, severe dehydration with vomiting, fever and ultimately die.
• Based on physical meteorological perspective, heat-wave events can be classified into 
• Dry heat wave
• Dry heat-waves are characterised by dry weather conditions with clear skies and large inputs of solar radiation
• Windy conditions can increase the heat stress
•  Dry heat waves usually occur where air is warmed adiabatically
• Moist heat waves
• They are characterized with  very warm, oppressive conditions throughout the day and night
• They normally occur under a cloud cover at night which prevents loss of accumulated heat during the day
• Such heat waves are a feature of mid-latitude temperate

• A heat wave is caused by a system of high atmospheric pressure
• In a high pressure system, air from upper levels of the atmosphere descends and rotates outward
• As it comes down, it becomes compressed, which increases the temperature

The following are the effects of a heat wave on the human body

1. Headaches
2. Muscular cramps
3. Swollen hands, feet and ankles
4. Appearance of heat rash on the skin
5. Unusual fatigue
6. General discomfort
7. Signs of dehydration like
1. Excessive thirst
2. Less frequency of urination
3. Dark urine
4. Dark skin
5. Rapid pulse and breathing

 Medical intervention is required in the following situations

1. Difficulty breathing
2. Convulsions
3. Deterioration of consciousness
1. Confusion
2. Unusual behaviour
3. Agitation
4. Hallucination
5. Lack of response to external stimuli
4. Loss of consciousness

Heat stroke is the most serious effect of heat. It can occur suddenly and quickly leas to death if not treated quickly. Signs of heat stroke are

1. Oral temperature more than 39.5 C and rectal temperature more than 40 C
2. Dry skin, hot and red 
3. Dizziness and vertigo
4. Confused and illogical speech
5. Aggressive or strange behaviour 
6. General discomfort

Role of PRi in Disaster Management

ROLE OF PANCHAYAT RAJ INSTITUTIONS (PRIs) IN DISASTER MANAGEMENT 

 The PRi is a statutory body elected by the local people through a well defined democratic process with specific responsibilities and duties. Elected members are accountable to the people of the ward, rural community, block and the district. The PRIi being a representative body of the people, is the most appropriate institution from the village to the district level in view of its proximity, universal coverage and enlisting people's participation on an institutionalized basis. Their close involvement is crucial in getting people prepared for countering natural disasters as well as involving people in all possible preventive and protective activities so that the impact of the disasters are mitigated and the people save their lives and property. PRis act as catalysts to social mobilization process an tap the traditional wisdom of local communities to complement modern practices in disaster mitigation efforts. PRis also provide a base for integration of various concerns of the community that of NGOs and CBOs that are engaged in various developmental activities at the grassroots level. If PRi's are not consulted for preparedness, planning, relief and rehabilitation work, it leads to lack of accountability and transparency resulting in loss of money.

Activities like distribution of immediate relief in the form of money, food grains, medical care, clothes, tent, vessels, drinking water and other necessities, activities of restoration, rehabilitation and reconstruction efforts of damaged villages and towns can be implemented better with the involvement of local bodies. PRi plays a crucial role in mobilizing people in various situations of crisis. The impact of disasters on people living in vulnerable areas and losses to their property can be minimized by a pro-active role played by PRis at the grassroots level. PRi members can play a role of leadership in disaster management at all stages.
Role played by PRis at various levels of disaster management is given below:

PRE-DISASTER
-Organizing awareness campaigen and promoting community education on disaster preparedness
-Articulation of community need for developing preparedness plan through community involvement and panchayat ownership
-Identifying the resource gaps both physical and manpower and replenish the same through capacity building
-Establishing synergy with local agencies including NGOs / CBOs
-Dovetailing risk reduction into various development programs of national and state governments
-Establish convergence with local institutional structures created for implementing education, health, livelihood, social justice, etc
-Activating the disaster management plans with the participation of the community
-Formation of task forces and their capacity building

DURING DISASTER
-Arranging emergency communication through available resources
-Evacuation to temporary shelter and running relief camps
-Supplementing rescue and relief efforts in coordinating different agencies
-Monitoring of relief distribution
-Safe disposal of carcass along with setting sanitation facilities and safe drinking water

POST DISASTER
-Damage assessment particularly assisting in identifying victims for compensation and its distribution
-Formulating rehabilitation and reconstruction plan of houses and other local infrastructure
-Enforce minimum specification for safe reconstruction
-Supervise and monitor long term reconstruction and mitigation projects
-Mobilising special funds to use disaster resistant construction technology in vulnerable areas.

Community Based DRR

COMMUNITY BASED DISASTER RISK REDUCTION

 

Community Based  Disaster Risk Reduction refers to locally appropriate and locally "owned" strategy for disaster preparedness and risk reduction.This has been designed to improve the effectiveness of specialist and non-specialist professionals in disaster response, helping them to link the disasters with risk reduction and development in a sustainable manner.

Communities are at the core of disaster risk reduction (DRR), and community based approaches are getting increasing focus in national DRR plans.

Reducing the risk and losses of disasters is a collective effort. It requires collective action.

Without engagement at the local level, it’s very difficult to cope with any disaster.

The following factors determine the success of a  Community Based  Disaster Risk Reduction (CBDRR) program:

1. Motivation and capacity of the community and community leaders
2. Motivation and capacity of community and the stakeholders coupled with the strength of partnerships between them
3. The capacity of external agencies and the strength of partnership with them
4. The level of community participation and ownership of the CBDRR program
5. The level of integration of CBDRR programs with other sectors
6. Maintaining an appropriate balance between standardisation and flexibility in terms of program design
7. Time constraints to implement CBDRR programs
8. Availability of funds to implement CBDRR programs
9. Presence of adequate assessment, monitoring and evaluation procedures

Community based Disaster Risk Reduction (CBDRR) is the core of any risk reduction program as communities are the first responders to any disaster. Disaster Risk Reduction focuses on reducing the underlying risk and encourages preventive action before a disaster. Communities become actively involved in search and rescue, relief and post-disaster recovery. CBDRR emerged as a result of shift from reactive emergency management to disaster risk reduction. In order to enhance community participation in before a disaster occurs, it is important to focus on risk reduction issues. This led to development of Community based Disaster Risk Reduction (CBDRR) . CBDRR focuses on predisaster interventions such as prevention, mitigation and preparedness related activities. Prevention aims at avoiding the occurrence of disasters. While this is not possible in the case of natural disasters, the intensity and frquency can be reduced by
-poverty alleviation
-asset redistribution plans
-provision of basic services such as education and health care
Mitigation measures reduce and limit the impact  of natural hazards on elements of risk such as population, infrastructure and properties through structural measures such as bridges, protective dykes, embankments and safety building design. Non-structural measures include community risk assessment, community risk reduction planning, public awareness, food security programs, group savings, cooperatives, strengthening community disaster management organizations and advocacy on disasters and development issues, legislation, land use zoning, etc. Disaster mitigation is an essential component of sustainable development. The essential elements and features of CBDRR form the core of community based approaches for disaster risk reduction. They are
-People's participation
-Setting priorities for the most vulnerable groups, families and people in the community
-Community-specific risk reduction measures
-Recognition of existing capacities and coping mechanisms
-Understanding the link between disaster risk reduction and development
-Supporting and facilitating role of exterternal (non-government) agencies

Community based approaches can be defined as a broad coverage of approaches that involve beneficiaries in their identification, design and management. It also refers to a collection of approaches applied within community level projects or as part of national programs. It also varies from consultation with communities to decision making to devolution of resources at the community level.
Community based disaster risk reduction is important since
-People in the community are the ultimate sufferers
-The people of the community are the first responders who have an in-depth knowledge of the area
-External help take time to arrive at the area
-It has been proved that top-down disaster risk management and response programs fail to address specific local needs of vulnerable communities and ignore the potential of local resources.
-The top-doen disaster risk management approach may also increase people's vulnerability

CBDRR is a process in which risk communities are actively engaged in identification, analysis, treatment, monitoring and evaluation of disaster risks in order to reduce their vulnerabilities and enhance capacities. People are at the heart of decision making and implementation of disaster risk reduction activities.

Analysis of disaster management lifecycle

ANALYSIS OF THE DISASTER MANAGEMENT CYCLE

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. The Disaster management cycle illustrates the ongoing process by which governments, businesses, and civil society plan for and reduce the impact of disasters, react during and immediately following a disaster, and take steps to recover after a disaster has occurred. Appropriate actions at all points in the cycle lead to greater preparedness, better warnings, reduced vulnerability or the prevention of disasters during the next iteration of the cycle. The complete disaster management cycle includes the shaping of public policies and plans that either modify the causes of disasters or mitigate their effects on people, property, and infrastructure.
The mitigation and preparedness phases occur as disaster management improvements are made in anticipation of a disaster event. Developmental considerations play a key role in contributing to the mitigation and preparation of a community to effectively confront a disaster. As a disaster occurs, disaster management actors, in particular humanitarian organizations, become involved in the immediate response and long-term recovery phases. The four disaster management phases need not necessarily occur in isolation or in this precise order. Often phases of the cycle overlap and the length of each phase greatly depends on the severity of the disaster.

• Mitigation - Minimizing the effects of disaster.
  Examples: building codes and zoning; vulnerability analyses; public education.
• Preparedness - Planning how to respond.
  Examples: preparedness plans; emergency exercises/training; warning systems.
• Response - Efforts to minimize the hazards created by a disaster.
  Examples: search and rescue; emergency relief .
• Recovery - Returning the community to normal.
  Examples: temporary housing; grants; medical care. 

Mitigation
Mitigation activities actually eliminate or reduce the probability of disaster occurrence, or reduce the effects of unavoidable disasters. Mitigation measures include building codes; vulnerability analyses updates; zoning and land use management; building use regulations and safety codes; preventive health care; and public education.
Mitigation will depend on the incorporation of appropriate measures in national and regional development planning. Its effectiveness will also depend on the availability of information on hazards, emergency risks, and the countermeasures to be taken. The mitigation phase, and indeed the whole disaster management cycle, includes the shaping of public policies and plans that either modify the causes of disasters or mitigate their effects on people, property, and infrastructure.
 
Preparedness
The goal of emergency preparedness programs is to achieve a satisfactory level of readiness to respond to any emergency situation through programs that strengthen the technical and managerial capacity of governments, organizations, and communities. These measures can be described as logistical readiness to deal with disasters and can be enhanced by having response mechanisms and procedures, rehearsals, developing long-term and short-term strategies, public education and building early warning systems. Preparedness can also take the form of ensuring that strategic reserves of food, equipment, water, medicines and other essentials are maintained in cases of national or local catastrophes.
During the preparedness phase, governments, organizations, and individuals develop plans to save lives, minimize disaster damage, and enhance disaster response operations. Preparedness measures include preparedness plans; emergency exercises/training; warning systems; emergency communications systems; evacuations plans and training; resource inventories; emergency personnel/contact lists; mutual aid agreements; and public information/education. As with mitigations efforts, preparedness actions depend on the incorporation of appropriate measures in national and regional development plans. In addition, their effectiveness depends on the availability of information on hazards, emergency risks and the countermeasures to be taken, and on the degree to which government agencies, non-governmental organizations and the general public are able to make use of this information.

Response
The aim of emergency response is to provide immediate assistance to maintain life, improve health and support the morale of the affected population. Such assistance may range from providing specific but limited aid, such as assisting refugees with transport, temporary shelter, and food, to establishing semi-permanent settlement in camps and other locations. It also may involve initial repairs to damaged infrastructure. The focus in the response phase is on meeting the basic needs of the people until more permanent and sustainable solutions can be found. Humanitarian organizations are often strongly present in this phase of the disaster management cycle.
 
Recovery
As the emergency is brought under control, the affected population is capable of undertaking a growing number of activities aimed at restoring their lives and the infrastructure that supports them. There is no distinct point at which immediate relief changes into recovery and then into long-term sustainable development. There will be many opportunities during the recovery period to enhance prevention and increase preparedness, thus reducing vulnerability. Ideally, there should be a smooth transition from recovery to on-going development.
Recovery activities continue until all systems return to normal or better. Recovery measures, both short and long term, include returning vital life-support systems to minimum operating standards; temporary housing; public information; health and safety education; reconstruction; counseling programs; and economic impact studies. Information resources and services include data collection related to rebuilding, and documentation of lessons learned.

Disaster Cycle

The disaster life cycle includes several phases:

• Mitigation: Disaster mitigation work involves directly preventing future emergencies and/or minimizing their negative effects. It requires hazard risk analysis and the application of strategies to reduce the likelihood that hazards will become disasters, such as flood-proofing homes or buying insurance. 

 

• Disaster preparedness: Disaster preparedness efforts include plans or preparations made in advance of an emergency that help individuals and communities get ready. Such preparations might include the stocking of food and water, or the gathering and screening of willing volunteers.

 

• Disaster response: Disaster response work includes any actions taken in the midst of or immediately following an emergency, including efforts to save lives and to prevent further property damage. Ideally, disaster response involves putting already established disaster preparedness plans into motion. Typically, this phase of the disaster life cycle draws the most attention.

 

• Disaster recovery: Disaster recovery happens after damages have been assessed, and involves actions to return the affected community to its pre-disaster state or better – and ideally to make it less vulnerable to future risk. Risk identification includes understanding the nature of hazards as well as understanding the nature of vulnerabilities. Subsequent efforts may range from physical upgrades to education, training, and public awareness campaigns.

This is depicted diagrammatically below:

culture of safety

CULTURE OF SAFETY:

Safety ofpeople in a community depends on several factors such as; training, and the systems, protocols and technology in place to prevent incidents from becoming disasters. This concept should
be deeply important as a community wide culture of safety. In order to improve the culture of safety in a community, major disasters in the past should be analysed in the contestxt of safety.
Thus, culture of safety is defined as "the individual and group values, attitudes and patterns and behaviour determine the commitment to, style and efficiency of a community's health and safety program"
It was found that tolerance of inadequate systems was thew most common cause of failures; as well as acceptance of deviance, production pressure and complacency. Experrs in the field of safety
propound that "it is not possible to be safe without a supporting culture and that "improvement in safety performance is only possible by improving or establishing a culture of safety". Culture of safety
can be brought about by introducing:

• Safety Culture Improvement tool and
• Safety culture metrics.

Safety culture improvement tool involves an audit of the health and safety management systems currently in place and suggest ways to improve these systems
Safety culture metrics focusses on quality of safety activities rather than the quantity and compares current activities to those of an earlier time frame

Culture of safety cannot be  measured with any level of precision but can be assessed.
Metrics have been developed to enable leaders to track the things they do on a day-to-day basis and identify areas with weakest performance. Experts recommend that basic safety training should be imparted to workers and employees and establish a culture of safety at the workplace and thus minimize
the occurrence of accidents. The fundamental objective of having a culture of safety  not only enhances working environment but also increases the overall productivity. It should be the the aim of every 
industrialist to use safe industrial equipment and products along with providing a safe working environment to his employees.

QUIZ-I

QUIZ-I

Covering Unit-I & Unit-II

Answer ALL

1. A disaster is a __________, ____________ event that seriously disrupts the functioning of a community or society and causes __________, ___________, and _____________ or environmental losses that exceed the ________________ or _____________ ability to cope using its own resources
2. List four examples of natural disasters
3. How can the impact of disasters be minimized
4. Define disaster, Hazard and the three components of vulnerability
5. What is risk and express risk as a formula
6. List two examples of man-made disasters
7. List the various impacts of droughts
8. List the indirect effects of drought
9. List the negative effects of drought on people. 
10. List the economic impacts of drought
11. Explain briefly, the political impact of drought as a "focussing event".
12. List few environmental impacts of droughts
13. List the various impacts (six typical and ten delayed) of drought on the health of a community
14. List the various disasters that the Indian subcontinent and the northern himalayan region are prone to
15. What percentage of India is prone to drought, earthquake, floods and cyclones.
16. List the various major famines in India
17. What is the average drought frequency in India
18. Who are the worst affected by droughts
19. What are the two broad classifications of disasters in India
20. What is the meaning of Hydrometeorology and list examples of hydrometeorological disasters
21. What are geological disasters also known as 
22. List examples of geological disasters
23. List the common characteristics of natural disasters
24. State the conceptual and operational definitions of drought
25. List the various types of drought
26. List the causes of drought
27. List the various direct and indirect impacts of drought
28. List the economic, environmental and social impacts of drought
29. What is the impact of drought on the health of a community
30. List the initial and delayed responses with regard to psychosocial impacts of drought on people in the affected community
31. Explain in brief the phrase, "differential impacts of disasters"
32. What is meant by "global trends"
33. List the factors contributing to an increasing trend in number of disasters over the past few decades
34. What is an urban disaster
35. Define pandemics
36. List the four types of stability found in complex emergencies
37. List the factors contributing to rapid climate change
38. Why are slums in cities a major center of crime
39. List the reasons for high hazard intensity in urban areas
40. List examples of pandemics that occurred in the past
41. List the characteristics of complex emergencies
42. List the effects of national and international level complex emergencies
43. List the various climate change indicators
44. List the various risks due to climate change
45. List the direct and indirect impacts due to climate change
46. List the impacts that climate change has on ecosystems and environmental relationships
47. List the various causes due to floods and cyclones
48. Where are tropical cyclones generated
49. What is the 'eye' of a cyclone
50. What is the wind direction in a cyclone
51. What is an 'eye wall' and a 'rain band' in a cyclone
52. What causes 'local storms'
53. List the primary, secondary and tertiary hazards due to a cyclone with examples
54. List the damage caused due to local storms
55. Define atmospheric hazards. What are they also known as 
56. What is a cumulative atmospheric hazard
57. List the various atmospheric hazards
58. List the common types of toxic gases encountered in confined spaces
59. Define a cold wave and list the criteria for determining a cold wave
60. List the effects of cold waves
61. Can cold waves be forecasted
62. Define heat wave and heat stress
63. On what basis are heat waves classified
64. List the characteristics of dry heat wave and moist heat wave
65. List the effects of heat wave on the human body
66. List the signs of heat wave
67. ___________% of rainfall occurs in ___________ months in India
68. Define flood
69. Floods in India are caused due to _________________________ basin that carries ___% of total river flow in India
70. List the various causes of floods in India
71. List the various flood prone regions of India
72. Define a road accident
73. List the various causes of traffic accident
74. List the elements of good driving
75. List the effects of a traffic accident

Urban disasters

URBAN DISASTER

An urban area can be defined as an area with large population and high density. An urban disaster occurs mainly due to urbanization. Urban cities have lifelines like electricity line, water line, sewage
line, telephone line etc.
Urbanization of the world's population is accelerating. More than 50% of the global population is already urban with more than one billion people living in slums. This trend continues and it is estimated that by 2050 more than 67% of the world's population will be living in cities.

Based on the damage caused, urban disasters are classified into:

1. Urbanizing natural disaster is seen mostly in the developing world where substantial natural environment is not affected by human activities. It mainly occurs when residential areas and urban infrastructure are developed in rural areas.
2. Pseudo-urban natural disasters are disasters where there is little or no damage to human life whereas urban infrastructure and lifeline systems are completely destroyed. In such type of disasters, population density is not large and only property damages are prevalent.
3. Urban natural disasters are disasters that are largely amplified due to overpopulation and socioeconomic activities.

Urbanization is a major cause of concern in the current time due to the following reasons:

1. The marginalized rural populace invariably lives a nomadic life, constantly on the move, in search of a better life. They live as workers in rural areas toiling in agricultural fields or performing menial jobs
2. Upon arrival in urban cities, they are attracted to the luxurious and comfortable lifestyle preferring to stay back and work as unskilled laborers in the organized as well as unorganized job sector. This leads to formation of slums that lack sanitation services, supply of clean water, reliable electricity, law enforcement and other basic services.
3. Hence, slums in urban cities are a major centres of crime. Lack of healthy environment contributes to vector borne diseases that become the epicenter of epidemics
4. Statistics indicate that crimes originate in slums and spread across entire metropolitan cities making it an unsafe place to stay

EFFECT OF POPULATION ON URBAN NATURAL DISASTER

1. Ratio of amplification
2. Effect of population density on disasters

Urban natural disasters are characterized by catastrophe due to overpopulation and dense concentration of social capital which has not invested enough for disaster prevention. Highly populated cities amplifies the injury to its inhabitants and damage to property.

Other type of urban disasters include:

1.  Chernobyl nuclear disaster that devastated Pripyat city that was a major bustling center of activity
2. 1926 Miami hurricane, Hurricane of 1900 in Galveston, TX, 1994 Earthquake in Northridge, CA, Kanto Earthquake in 1923, Earthquake in San Francisco in 1906, Hwang He floods in 1931 in China, Tropical cyclone in Bangladesh in 1998.
3. The great Chicago fire in1871, Starvation in Bengal in 1943,

Higher losses of life and property in a given hazard intensity in urban areas are due to:

1. Increasing urbanization
2. Expansion of habitat into unsuitable vulnerable areas
3. Higher population densities
4. Vulnerable construction due to loss of traditional skills 
5. Ignorance, apathy and the false belief that disaster will not occur in the area
6. Complacency due to long gap between two events
7. Non-engineered unsafe construction
8. Structurally unsound and unauthorized vertical constructions and additions to houses

ASSIGNMENT QUESTIONS

ASSIGNMENT QUESTIONS

1. Define and discuss risk and capacity with respect to disasters
2. What is mitigation and discuss the structural measures to mitigate the effect of floods

1. Discuss with the help of an example, artificial floods in urban areas
2. Discuss forest fires as natural and man made disaster with the help of an example

1. Discuss the ecological impacts of various types of disasters with examples
2. Discuss climate change as a disaster

1. Write short notes on climate change adaptation
2. List the local resources that can be used in disaster management

 

1. Briefly explain sanitation and shelter as components of disaster relief
2. List the salient features of DM act and DM policy

Classification, causes and impacts (social, economic, political, environmental, health and psychosocial) of disasters

Classification of disasters:
Disasters are primarily classified as:

1. Natural disasters and
2. Man-made disasters

Natural disasters are caused due to natural phenomena. Examples are:

• Floods
• Droughts
• Cyclones
• Earthquakes
• Tsunamis
• Volcanoes
• Landslides
• Avalanche
• Blizzard (Snow storm)
• Wind chill
• Sand storms

Man-made disasters are caused primarily due to human negligence. Examples are:

• Explosions
• Leakage of toxic chemicals
• Pollution
• Deforestation, Forest fires
• Dam failure
• Wars, Weapons of mass destruction (WMD), Biological weapons, Chemical weapons, etc.

Natural disasters can further be divided into 

• Hydrometeorological based disasters and
• Geological based disasters

Hydrometeorology is the study of exchange of energy and water between the lower atmosphere and Earth's surface. Examples of hydrometeorological disasters are:

• Cyclone
• Flood
• Drought
• Wind chill
• Snow storm
• Sand storms. etc

Geology is the science of study of the Earth. Examples of geological based disasters are:

• Earthquake
• Volcano
• Landslide
• Tsunami, etc

Earthquake:

The Earth is made-up of rocks, tectonic plates and molten magma at the core. The tectonic plates are in constant motion relative to each other. As the plates move against each other, any irregularity causes an abrupt jerk resulting in tremendous energy being released which is experienced on the surface as an Earthquake.

Volcano:
The Earth's core is made up of molten magma under pressure. When this molten magma finds its way to the surface of the Earth through cracks or fissures it erupts with great force spewing red hot lava. Volcanoes occur under the oceans on the sea bed also. They cause severe damage to life and property. Sometimes volcanoes remain dormant for several years before becoming active again. In the past, volcanoes have occurred in Italy(Mount Etna), Indonesia(Mount Merapi), Japan(Sakurajima), United States(Mount St. Helens), Ethiopia(Erta Ale), etc.

Landslide:
Landslide refers to a type of mass wasting. Examples include:

• Rock falls
• Deep seated slope failures
• Mud flow and
• Debris flow

Tsunami:
Tsunami is Japanese meaning tidal wave or  a  harbour wave. It occurs due to disturbances in the sea floor. It is a series of waves in a water body caused by displacement of large volume of water in an ocean.

Disasters are also classified as:

• Extraterrestrial disasters: These types of disasters are caused by collision of celestial bodies. Space telescope data reveals 4700 potentially hazardous asteroids with diameter greater than 330 feet are present near the Earth. Other types of extraterrestrial hazards are:
• Magnetic storms
• Catastrophic Earth changes
• Meteorite Impacts and
• Impacts from near-earth objects

Man-made disasters:

• These hazards man-made or human induced disasters. They are caused primarily due to human activities leading to loss of life and property along with causing damage to the regions economy and productive capacity. Examples of these disasters are:
• Environmental pollution
• Terrorism
• Destruction of property
• Road & rail accidents
• Explosions
• Chemical spills
• Industrial accidents
• Nuclear accidents, etc.
• Physical hazards that are caused due to developmental activities. Examples include:
• Deforestation
• Desertification
• Loss of natural resources
•  Pollution
• Waste disposal, etc.
• Technological hazards that are caused due to interaction of society, technology and the natural environment. Examples include:
• Explosions
• Wars
• Release of  toxic substances into the environment
• Oil spills, etc

Environmentalists have further categorized technological hazards into:

• Industrial Hazards
• Structural collapse hazards
• Nuclear hazards
• Computer hazards and
• Transportation hazards

Biological hazards or biohazards:

• These type of hazards originate from biological sources. Examples are:
• AIDS
• Malaria
• Severe epidemics in plants and animals (SARS)

Biohazards are further categorised into:

• Pathogens (Example: Anthrax, Small Pox, Influenza, Plague etc)
• Toxins 

Social hazards originate from social systems such as:

• Population explosion
• Famine
• Warfare
• Conflict
• Terror attacks
• Holding people hostage etc

Causes of disasters:

• Earthquakes are mainly caused by slippage within geological faults but also due to volcanic activity, landslides, mine blasts and nuclear tests.
• Landslide is a geological phenomenon that includes a wide range of ground movements like rock falls, deep failure of slopes and shallow debris flow that occurs offshore, coastal and onshore environments.Gravity is the primary driving force along with contributing factors like slope stability.
• Tsunami is a series of water waves caused by displacement of large body of water. The 2004 Indian ocean tsunami was the deadliest in human history causing the death of 2,30,000 people in the countries surrounding the Indian ocean.
• A volcano is a rupture in the Earth's crust that allows hot magma and volcanic ash from the Earth's interior to erupt on the Earth's surface.
• A flood is an overflow of water that submerges vast areas of land. Floods occur in rivers when flow capacity exceeds the capacity of the channel
• Landslides also called a landslip or mudslide occurs when the slope changes from a stable to an unstable condition due to groundwater pressure, weakening of a slope due to saturation from snow melt or heavy rainfall. Landslides are also caused due to deforestation, mining at the foot of the slope, excess withdrawal of ground water, construction activity and explosive activity in the vicinity
• Droughts are caused due to less or no rainfall combined with excessive withdrawal of groundwater.
• Snow storms and sand storms occur in cold and desert regions respectively. Snow storms occur in the cold mountainous regions and consist of freezing winds combined with snow reducing visibility and related hazardous conditions. Sand storm is a meteorological phenomena in arid and semi-arid regions. Sand storms may cause asthma and other related respiratory problems. Sand storms or dust storms involve transport of fine sand particles from one place to another. A sand storm can transport and carry large volumes of sand unexpectedly.

Impacts of disasters:
Disasters may have the following effects on communities as listed below.

1. Social impacts: The social impacts of a disaster refer to the tangible and intangible effects on a society and the expenses to rebuild the society to the stage that existed before the disaster occurred. The most common social impacts on a community involve:
1. increased mental health issues
2. alcohol misuse
3. domestic violence
4. chronic diseases and
5. short-term unemployment
2. Economic impacts: Any disaster destroys tangible assets such as buildings and equipment. Disasters have severe short-term economic impacts. The costs of disasters rise exponentially with economic development. Disasters affect the infrastructure of a community in a manner that all other projects requiring funds are stopped and diverted to reconstruction and rehabilitation work
3. Political Impacts: Disasters fundamentally test a government's preparedness and capacity to deal with a disaster. Government's should be aware of natural disaster risks in their region and set regulatory measures in place before the disaster occurs. If a government has done a poor job responding to a disaster they may be voted out or political unrest may occur in response to a disaster.
4. Environmental impacts: Disasters have a profound effect on the environment. They cause a temporary or permanent effect on the environment depending the type of disaster. Earthquakes modify the topography of the terrain, Volcanoes release several tons of carbon-dioxide and other toxic gases. In addition, they destroy the local landscape and anything that comes in contact. Floods cause widespread destruction of the local region and habitat. They also cause loss of life and severe erosion.
5. Health impacts: Disasters impact the health of affected people in several ways. People may suffer from physical injuries that may be temporary or permanent. Affected people may suffer psychologically and suffer from mental illnesses. The health effects may last much longer than the disaster itself. The health effects of a disaster are unavoidably linked to the social and economical effects of any disaster.
6. Psychosocial impacts: Psychosocial impacts refers to the effect caused by the environment on the social and or psychological aspect on an individual or community due to a disaster. Several psychiatric disorders may affect psychological and social aspect of the affected individual's life. Disasters may diseases such as PTSD, depression, extreme stress, anxiety and a range of mental diseases.

Review of past disasters and drought in India

REVIEW OF PAST DISASTERS IN INDIA

The Indian subcontinent is highly vulnerable to cyclones, droughts, earthquakes and floods. Avalanches, forest fire and landslides occur frequently in the Himalayan region of northern India. On an average, about 50 million people in the country are affected by one or the other disaster every year, besides loss of property worth several million.

In the 1970s and the 80s, droughts and famines were the biggest killers in India. Floods, high winds and earthquakes dominate the reported injuries, with increasing numbers in the last ten years. The period from 2001 to 2011 has been associated with a large number of earthquakes. Floods, droughts, cyclones, earthquakes, landslides and avalanches are some of the major natural disasters that repeatedly and increasingly affect India. The natural disasters directly impact economies, agriculture, food security, water, sanitation, the environment and health each year.

 Different natural hazards because varying levels of physical damage to infrastructure and agriculture with implications for their indirect and secondary impacts. Drought causes heavy Crop and Livestock losses over wide areas of land.  Floods and Cyclones cause extensive whereas damage to both infrastructure and agriculture, depending on their timing relative to the agricultural cycle. Earthquakes can cause wide spread devastation of infrastructure and other productive capacity over relatively large areas.

During the period 1980 - 2010 India faced disasters in the form of floods (in 1980, 1982, 1993, 1994, 1995, 1998, 2002, 2004, 2005, 2006 and 2009), drought (in 1982, 1987, 2000 and 2002), earthquake (in 1993, 2001 and 2004), epidemics (in 1984 & 1988), storm (in 1990, 1996, 1998 & 1999)

India is a country highly vulnerable to natural disasters. Enormous population pressures and urbanization have forced people to live on marginal lands or in cities where they are at greater risk to disasters and the damage they can cause. Each time a flood, a regional drought or a devastating earthquake occurs, millions of Indians are affected. In addition to large-scale displacement and the loss of life, these events result in the loss of property and agricultural crops worth millions.

In India, 68 percent of the land is drought prone, 60 percent is prone to earthquake, 12 percent is prone to floods and 8 percent to cyclones. This amounts to almost 85 percent of the land area in India  vulnerable to natural hazards. The main natural disasters in India includes floods, earthquakes, droughts, and cyclones while the minor natural hazards in India are landslides, avalanches, hailstorms, forest fires and bush fires.

These disasters have been categorized into following five sub-groups depending on origin. They are:

1. Water and Climate Related Disasters Ex:Floods and Drainage Management, Cyclones, Tornadoes and Hurricanes, Hailstorm, Cloud Burst, Heat Wave and Cold Wave, Snow Avalanches, Droughts, Sea Erosion and Thunder and Lightning. 
2. Geologically related disasters Ex:Landslides and Mudflows, Earthquakes, Dam Failures/Dam bursts and mine fires
3. Chemical , Industrial & Nuclear related disasters Ex: Bhopal gas tragedy
4. Accident related disasters Ex:Forest Fires, Urban Fires, Mines Flooding Oil Spill, Major Building Collapse, Serial Bomb Blasts, Festival related disasters, Electrical disasters and Fires, Air, Road and Rail Accidents, Boat Capsizing and Village Fire.
5. Biologically related disasters Ex:Epidemics, Pest Attacks, Cattle epidemics and Food poisoning.

DROUGHT IN INDIA

India has a largely monsoon dependent irrigation network. An erratic pattern, both low (less than 750 mm) and medium (750 - 1125 mm) makes 68 percent of the total sown area vulnerable to periodic droughts. Severe and rare droughts occur in arid and semi-arid zones once in almost every 8-9 years. Drought is a perennial feature in some states of India. 16 percent of the country’s total area is drought prone and approximately 50 million people are annually affected by droughts. In fact, persistent drought with less than average rainfall over a long period of time gives rise to serious environmental problems.

Drought in India has resulted in millions of deaths in the past three centuries. Indian agriculture is heavily dependent on climate to irrigate crops. The southwest monsoon is essential for crops and its failure results in below average crop yields.

Sometimes, droughts have led to major famines for example:

1. The Bengal famine of 1770 (one third of population in affected area dead)
2. The famine in 1876-1877 (five million people dead)
3. The 1899 famine (4.5 million people dead)

Drought strikes India every eight to nine years. Drought impacts the poorest the hardest.