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.