Chapter 6 Natural Hazards And Disasters

We are often exposed to news or images of natural events like tsunamis or earthquakes, witnessing the devastating impact they can have on human life and property. These events are examples of rapid and significant changes occurring in our environment.

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Change is a fundamental aspect of nature, happening constantly at various scales and speeds. Some changes are gradual, like the slow evolution of landforms or species over geological time. Others are sudden and swift, such as volcanic eruptions, tsunamis, earthquakes, or lightning strikes. Changes can also vary in spatial extent, from localized events like hailstorms or tornadoes to global phenomena like climate change or ozone depletion.

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How we perceive these changes is often influenced by our human perspective. From nature's viewpoint, changes are neutral – simply processes occurring. However, humans tend to assign value, categorizing changes as desirable (like ripening fruit or changing seasons) or undesirable ("bad" events like earthquakes, floods, or wars) based on their impact on human well-being and society.

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This chapter focuses on some of the changes considered undesirable and feared by humankind – **disasters**, particularly natural disasters. These events cause significant harm and disruption.

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What Is A Disaster?

A **disaster** is defined as an unexpected and undesirable event, largely beyond human control, that strikes suddenly and causes or threatens severe disruption to life and property, including death and injury to many people. Disasters require a response effort greater than what is normally available from emergency services.

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Historically, disasters were often viewed solely as consequences of overwhelming natural forces, with humans as helpless victims. However, it is now recognized that while natural forces are triggers, **human activities** also play a significant role, both directly and indirectly, in causing or intensifying disasters.

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Examples of disasters directly caused by human actions (human-made disasters) include industrial accidents (like the Bhopal gas tragedy), nuclear disasters (Chernobyl), wars, and large-scale pollution (air, water, soil, noise). These have increased in frequency and magnitude.

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Human activities can also indirectly worsen natural hazards, turning them into major disasters. Examples include:

• **Landslides and floods** exacerbated by deforestation (removing vegetation that stabilizes slopes and absorbs water).
• **Unscientific land use** and construction in fragile or hazard-prone areas.

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While preventing natural hazards themselves is often impossible, mitigating their impact and managing the resulting disasters is crucial. This includes preparedness measures before an event, effective response during the event, and rehabilitation afterwards. International and national efforts, such as the establishment of the National Institute of Disaster Management in India, the Earth Summit in Rio de Janeiro (1992, not 1993 as stated in the text), and the World Conference on Disaster Management in Yokohama (1994), reflect a growing global commitment to disaster mitigation and management.

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It's important to distinguish between **natural hazards** and **natural disasters**. **Natural hazards** are natural environmental conditions or processes that have the potential to cause harm (e.g., steep slopes, strong ocean currents, extreme temperatures, fault lines). These are potential threats. A **natural disaster** is a relatively sudden event resulting from a natural hazard that actually causes large-scale death, widespread property loss, and significant disruption to social systems. A hazard becomes a disaster when its impact is severe and exceeds the coping capacity of the affected community.

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While each disaster is unique in its local context and social response, some key observations are clear: the magnitude, intensity, frequency, and damage from natural disasters have increased. There is growing global concern and effort to minimize losses. The pattern of disasters is also changing, partly due to increased human vulnerability.

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Technological advancements have increased human capacity to modify the environment, sometimes leading to intensification of activities in hazard-prone areas. Examples include building large cities and infrastructure in coastal zones vulnerable to cyclones and tsunamis, or developing settlements on floodplains. This increased human presence and development in vulnerable areas significantly enhances the potential for a hazard to become a major disaster.

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Data on deaths from historical disasters (Table 6.1, not provided here) would illustrate the severe human cost. The Yokohama Strategy and Plan of Action (1994) recognized that disasters disproportionately affect developing countries and vulnerable populations, emphasizing the need for national responsibility, international cooperation, capacity building, technology sharing, and resource mobilization for disaster prevention, mitigation, and preparedness.

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Classification Of Natural Disasters

Classifying disasters helps in better understanding and managing them. Natural disasters are often broadly classified based on the origin of the hazard. A common classification includes four main categories (Table 6.2, not provided here in detail, but typically grouped as):

1. **Atmospheric Disasters:** Caused by extreme weather events (e.g., cyclones, tornadoes, heatwaves, cold waves, blizzards, thunderstorms).
2. **Terrestrial Disasters:** Caused by Earth's internal or surface processes (e.g., earthquakes, volcanic eruptions, landslides, avalanches, soil erosion).
3. **Aquatic Disasters:** Caused by extreme water-related events (e.g., floods, tsunamis, storm surges, tidal waves, droughts - although drought is often categorized separately or as a meteorological/hydrological disaster).
4. **Biological Disasters:** Caused by biological agents (e.g., insect infestations, viral/bacterial epidemics, wild animal attacks).

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India is prone to a wide range of these natural disasters due to its vast geographical area, diverse physical environments, and socio-economic factors. Every year, natural calamities cause significant loss of life and property in India. The following sections discuss some of the highly devastating natural disasters relevant to India.

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Earthquakes

**Earthquakes** are among the most unpredictable and potentially destructive natural disasters. They are caused by a sudden release of energy within the Earth's crust, generating seismic waves that cause ground shaking. The most devastating earthquakes are typically of **tectonic origin**, resulting from the movement and interaction of large lithospheric plates along faults. Earthquakes associated with volcanic activity, landslides, mining subsidence, or reservoir impoundment are generally localized and cause less widespread damage compared to major tectonic events.

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As discussed in previous chapters, the Indian Plate is continuously moving northward and colliding with the Eurasian Plate. This collision causes stress and accumulation of energy along the plate boundary in the Himalayan region. When this accumulated stress exceeds the strength of the rocks, the plates suddenly slip, releasing energy as an earthquake. This makes the Himalayan region and northeastern India highly seismically active and vulnerable to devastating earthquakes.

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Highly vulnerable areas in India include Jammu and Kashmir, Ladakh, Himachal Pradesh, Uttarakhand, Sikkim, parts of West Bengal (Darjeeling), and all the northeastern states. These regions are often included in the "Very High Damage Risk Zone."

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While the Peninsular Block is generally considered stable, it has also experienced significant earthquakes, such as in Gujarat (Kachchh in 2001) and Maharashtra (Killari, Latur in 1993). Explaining earthquakes in this older, stable landmass has been challenging, though theories suggest the possibility of reactivation of ancient fault lines and energy build-up.

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Based on historical seismic activity and geological factors, India is typically divided into five earthquake zones ranging from Very High Damage Risk Zone (Zone V) to Very Low Damage Risk Zone (Zone I). Zone V and IV are most vulnerable. Areas in Zone V include parts of the Northeast, Bihar along the Indo-Nepal border, Uttarakhand, Western Himachal Pradesh, Kashmir Valley, and Kachchh (Gujarat). Zone IV includes the remaining parts of Jammu and Kashmir, Ladakh, Himachal Pradesh, Northern Punjab, Eastern Haryana, Delhi, Western Uttar Pradesh, and Northern Bihar. The most stable and safest areas (Zone II) are generally located on the Deccan plateau. (Figure 6.2 shows India's earthquake hazard zones).

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Socio-Environmental Consequences Of Earthquakes

Earthquakes trigger widespread fear due to their suddenness and potential for massive destruction. When strong earthquakes strike densely populated areas, they become major calamities. The impacts are devastating, affecting not only the natural environment but also human society and development. (Figure 6.1 shows damage from an earthquake).

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Socio-economic consequences include:

• Damage and destruction of buildings, infrastructure (roads, bridges, communication networks).
• Loss of industries and economic activities.
• Significant loss of life and injury.
• People rendered homeless, leading to displacement and requiring shelters and relief.
• Economic losses that can set back development, particularly in developing countries.

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Effects Of Earthquakes

Earthquakes have a wide range of direct and indirect effects (Table 6.1 provides a categorized list, notes are based on common knowledge and text description):

On Ground	On Man-made Structures	On Water
Ground Shaking	Structural Collapse	Generation of Waves
Fissures/Cracks in the ground	Cracking of Walls/Foundations	Hydro-Dynamic Pressure (affecting dams, etc.)
Landslides/Rockfalls (triggered by shaking)	Overturning of Objects/Structures	Tsunami (if underwater earthquake)
Liquefaction (saturated soil behaves like liquid)	Buckling of Buildings	Changes in Groundwater levels/flow
Ground Lurching (wavelike ground movement)	Increased Earth Pressure on retaining structures	Disruption of Drainage/River Courses
Possible Chain-effects (e.g., triggering other hazards)	Possible Chain-effects (e.g., fires, release of hazardous materials)	Possible Chain-effects (e.g., flooding, changes in water quality)

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Environmental consequences include ground fissures, liquefaction, landslides (blocking rivers and forming temporary lakes), and sometimes changes in river courses, potentially causing floods. Underwater earthquakes can generate tsunamis.

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Earthquake Hazard Mitigation

Earthquake mitigation is challenging because occurrence cannot be prevented, and damages are often widespread, disrupting relief efforts. The focus is on **disaster preparedness and mitigation** before an earthquake strikes:

• **Monitoring and Information Dissemination:** Establishing seismological centers to monitor seismic activity and quickly alert people in vulnerable areas. Using technologies like GPS to track plate movements can help in long-term risk assessment.
• **Vulnerability Mapping and Education:** Creating maps showing areas vulnerable to earthquakes and educating the public in these regions about the risks and measures to minimize damage.
• **Land Use Planning and Building Codes:** Modifying building designs in vulnerable zones to be earthquake-resistant, discouraging the construction of high-rise buildings or large industrial facilities in very high-risk areas, and avoiding dense urbanization in such regions.
• **Mandatory Earthquake-Resistant Construction:** Implementing and enforcing building codes that require earthquake-resistant designs and the use of lighter, safer materials in construction, especially in vulnerable zones.

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Community preparedness, including evacuation plans and emergency supplies, is also essential.

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Tsunami

**Tsunamis** (meaning "harbour waves" in Japanese) are series of extremely large waves in a body of water, usually the ocean, caused by sudden displacement of a large volume of water. This displacement is most often triggered by powerful **underwater earthquakes**, but can also be caused by volcanic eruptions, submarine landslides, or even asteroid impacts. Unlike regular waves generated by wind, tsunami waves involve the entire water column, from the surface to the seafloor.

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A generating event typically produces one main vertical wave pulse, followed by a series of afterwaves as the water oscillates to restore equilibrium. The speed of a tsunami wave depends on the depth of the water ($v = \sqrt{gd}$, where $g$ is acceleration due to gravity and $d$ is water depth). Tsunamis travel much faster in deep ocean water than in shallow water.

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In the deep ocean, tsunamis have a very long wavelength (distance between crests, often hundreds of kilometers) and a relatively small wave height (maybe only a meter or two). They are difficult to detect from a ship in deep water and are not particularly dangerous there. They are sometimes called "Shallow Water Waves" because their speed is governed by depth.

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As a tsunami approaches a coastline and enters much shallower water, its speed decreases dramatically. However, the energy is conserved, forcing the wave to become much shorter in wavelength and grow significantly in height. This process, known as **shoaling**, can result in towering waves up to 15 meters or more upon reaching the shore, causing massive destruction.

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Tsunamis are most frequent in the **Pacific Ring of Fire** due to the high seismic activity along convergent plate boundaries. Regions vulnerable to tsunamis include coasts bordering the Pacific (Alaska, Japan, Philippines, Southeast Asia, Indonesia) and the Indian Ocean (Indonesia, Malaysia, Myanmar, Sri Lanka, India) where seismic activity occurs near subduction zones.

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When a tsunami hits a coast, the waves release immense energy, causing turbulent flooding (inundation) that can sweep away buildings, infrastructure, settlements, and everything in its path. Coastal areas are often densely populated and economically vital, making the potential loss of life and property from a tsunami extremely high.

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Mitigating the damage from tsunamis is challenging due to their scale and suddenness. Individual countries' capacity is often insufficient, highlighting the need for **international cooperation**, particularly in establishing early warning systems. Following the devastating 2004 Indian Ocean Tsunami, which caused widespread loss of life across multiple countries, India joined the International Tsunami Warning System. This system uses seismic monitoring, deep-ocean pressure sensors, and communication networks to detect tsunamis and issue timely warnings to coastal populations, allowing for evacuation.

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Tropical Cyclone

**Tropical cyclones** are intense, low-pressure weather systems that form over warm tropical oceans. They are characterized by high-velocity spiraling winds converging towards the low-pressure center (the 'eye'). They typically form between $5^\circ$ and $30^\circ$ North and South latitudes (requiring sufficient Coriolis force for rotation, thus not forming very close to the equator).

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A tropical cyclone acts like a heat engine, drawing energy from the release of **latent heat** when moist air rising from the warm ocean surface condenses into towering thunderstorms (cumulonimbus clouds). This continuous supply of warm, moist air fuels and intensifies the storm.

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Initial conditions favorable for tropical cyclone formation and intensification include:

• A large area of **warm ocean water** (sea surface temperature typically above $27^\circ\text{C}$) to provide moisture and heat.
• Sufficient **Coriolis force** to initiate rotation (hence, they don't form near the equator).
• **Low vertical wind shear** (small variation in wind speed and direction with height) to allow the storm's structure to organize vertically.
• A pre-existing area of **weak low pressure** or a disturbed weather area at the surface to act as a trigger.
• Upper-level **divergence** (air flowing outwards from the top of the storm) to remove rising air and maintain the low pressure at the surface.

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Spatio-Temporal Distribution Of Tropical Cyclone In India

India's peninsular shape, surrounded by the Bay of Bengal and the Arabian Sea, makes its coastal areas vulnerable to tropical cyclones originating in these two basins. While cyclones can occur during the monsoon season (June-September), they are most frequent and severe in the **pre-monsoon** (April-May) and **post-monsoon** (October-November) seasons. This post-monsoon period, particularly October and November, sees the maximum cyclone activity in the **Bay of Bengal**. Cyclones typically originate over the central and southern Bay of Bengal and move westward or northwestward towards the Indian coast. In July, the origin might shift slightly northwards. Cyclones in the **Arabian Sea** are generally less frequent and less intense than those in the Bay of Bengal.

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Areas vulnerable to tropical cyclones in India are the coastal regions, particularly along the eastern coast (West Bengal, Odisha, Andhra Pradesh, Tamil Nadu) and the western coast (Gujarat, Maharashtra, Goa, Karnataka, Kerala). (Figure 6.4 shows the wind and cyclone hazard zones in India).

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Consequences Of Tropical Cyclones

The most destructive impacts of tropical cyclones occur along the coasts due to their proximity to the energy source (warm ocean). The intensity decreases with distance inland. Consequences include:

• **High Velocity Winds:** Can cause widespread structural damage to buildings, infrastructure, and vegetation.
• **Torrential Rainfall:** Leading to severe flooding in coastal and inland areas.
• **Storm Surge:** An abnormal rise in sea level pushed by the cyclone's strong winds and low pressure. This is often the most devastating impact in coastal areas, causing extensive inundation of human settlements, agricultural fields, and wetlands, resulting in loss of life and property. (Figure 6.3 shows a tsunami-affected area, which visually represents the inundation impact also caused by storm surges).

• Damage to crops and disruption of agriculture.
• Salinization of soil in coastal agricultural areas due to inundation by saltwater.

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Floods

**Flooding** occurs when the volume of water in a river channel or other natural water body exceeds its capacity, causing the water to overflow onto the surrounding land, inundating areas that are normally dry (floodplains and settlements). Unlike sudden disasters like earthquakes, floods are often relatively slower in onset and tend to occur in predictable regions and seasons, particularly during or after periods of heavy rainfall or snowmelt.

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Causes of floods include:

• Surface runoff exceeding the carrying capacity of river channels.
• High intensity rainfall over a prolonged period.
• Melting of ice and snow (especially in mountainous regions).
• Reduction in the rate at which water can infiltrate into the soil (e.g., due to saturated soil or impermeable surfaces).
• Sediment accumulation in river channels, reducing their capacity.
• Obstruction of drainage channels.
• Storm surges (causing coastal flooding during cyclones).
• Dam or levee failures.

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Floods are frequent and devastating in many parts of the world, particularly in densely populated river plains of South, Southeast, and East Asia (China, India, Bangladesh). (Figure 6.6 shows flood hazard zones in India, and Figure 6.5 shows a flood scene). (This refers to Figure 6.6 and 6.5).

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Human activities play a significant role in increasing the risk and severity of floods:

• Indiscriminate **deforestation** (reducing soil's ability to absorb water and increasing runoff).
• Unscientific **agricultural practices** (e.g., farming on steep slopes).
• **Disturbances** and encroachment along natural drainage channels and riverbeds.
• **Colonization of floodplains**, putting settlements and infrastructure at risk.

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In India, approximately 40 million hectares of land are identified as flood-prone. States like Assam, West Bengal, and Bihar in the Ganga-Brahmaputra basin are highly vulnerable to recurrent floods. Rivers in northern states like Punjab and Uttar Pradesh also experience occasional floods. In recent decades, parts of Rajasthan, Gujarat, Haryana, and Punjab have also experienced **flash floods** (sudden, intense floods, often due to heavy rain over a short period), partly linked to changes in monsoon patterns and partly due to human-induced blockage of drainage channels. Tamil Nadu sometimes experiences flooding during the retreating monsoon season (November-January) due to rainfall from the northeast monsoon and cyclonic depressions.

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Consequence And Control Of Floods

Floods have severe consequences for the national economy and society, particularly in vulnerable regions:

• Destruction of crops and agricultural land.
• Damage to physical infrastructure (roads, railways, bridges).
• Damage and destruction of human settlements, rendering millions homeless.
• Loss of human life and livestock.
• Spread of waterborne diseases (cholera, gastro-enteritis, hepatitis) in affected areas due to contaminated water.

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While often devastating, floods can also have some minor positive effects, such as depositing fertile silt on agricultural fields, enhancing soil fertility (e.g., in riverine islands like Majuli). However, these benefits are usually outweighed by the extensive losses.

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Flood control and management measures are crucial. Government responses typically include:

• Construction of **flood protection embankments** (levees) along vulnerable river banks.
• Building **dams and reservoirs** in the upper reaches of rivers to store excess water and regulate flow downstream.
• **Afforestation** (tree planting) in river catchments to improve soil's water absorption capacity and reduce runoff.
• Discouraging major **construction activities** in vulnerable floodplains and upper catchment areas.
• Removing human **encroachment** from river channels and depopulating high-risk floodplains.
• Establishing and managing **cyclone shelters** in coastal areas vulnerable to storm surges and floods.

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Droughts

A **drought** is a prolonged period of water shortage. It occurs when water availability falls significantly below normal levels due to insufficient precipitation, excessive evaporation, or overuse of existing water sources (reservoirs, groundwater). Drought is a complex phenomenon influenced by meteorological factors (rainfall, evaporation), hydrological conditions (groundwater levels, reservoir storage), agricultural practices, socio-economic factors, and ecological conditions.

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Types Of Droughts

Droughts can be categorized based on the aspect of the water cycle they affect:

• **Meteorological Drought:** Defined by a significant deficit in precipitation (rainfall) over a specific period compared to the long-term average for that area. This is the initial form of drought.
• **Agricultural Drought (Soil Moisture Drought):** Occurs when there is insufficient soil moisture to support crop growth, leading to crop stress and failure. This is a consequence of meteorological drought and depends on soil type and agricultural practices. Areas with high irrigation coverage are generally less susceptible to agricultural drought.
• **Hydrological Drought:** Results from deficits in surface and subsurface water supplies. It occurs when streamflow, lake levels, reservoir storage, and groundwater levels fall below average and are not replenished by precipitation.
• **Ecological Drought:** Occurs when a natural ecosystem's productivity is severely reduced due to water shortage, leading to ecological stress, damage, and potential loss of biodiversity.

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Various parts of India experience recurrent droughts, leading to serious socio-economic and ecological problems, including food and water scarcity, livestock losses, and migration.

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Drought Prone Areas In India

Indian agriculture is heavily reliant on monsoon rainfall, making large areas vulnerable to droughts. While floods and droughts can occur simultaneously in different regions due to the monsoon's variability, certain areas are more chronically drought-prone. Estimates suggest that about 19% of India's geographical area and 12% of its population are affected by drought annually, and roughly 30% of the total area is identified as drought-prone, impacting around 50 million people.

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Based on the severity and recurrence of droughts, India is broadly divided into regions (Figure 6.7 illustrates these zones).

• **Extreme Drought Affected Areas:** Include most of Rajasthan, particularly west of the Aravalli range (Marusthali), and the Kachchh region of Gujarat, characterized by very low rainfall (less than 90 mm annually in Jaisalmer and Barmer).
• **Severe Drought Prone Area:** Covers parts of eastern Rajasthan, most of Madhya Pradesh, eastern Maharashtra, interior parts of Andhra Pradesh and Karnataka Plateau, northern interior Tamil Nadu, and southern parts of Jharkhand and interior Odisha.
• **Moderate Drought Affected Area:** Includes northern parts of Rajasthan, Haryana, southern districts of Uttar Pradesh, remaining parts of Gujarat and Maharashtra (excluding Konkan), Jharkhand, and the Coimbatore plateau of Tamil Nadu and interior Karnataka.

Other parts of India are considered less prone or free from drought risk.

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Consequences Of Drought

Droughts have devastating, cascading effects, impacting food security, water availability, and human/animal health. The most severe form is 'Trikal' - scarcity of food (akal), fodder (trinkal), and water (jalkal) simultaneously. (Figure 6.8 shows a drought scene). (This refers to Figure 6.8).

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Consequences include:

• Widespread crop failure and food shortages.
• Scarcity of fodder for livestock, leading to death of cattle and other animals.
• Mass migration of people and livestock in search of food, water, and livelihood.
• Severe shortage of drinking water, forcing people to use contaminated sources.
• Spread of waterborne diseases (gastro-enteritis, cholera, hepatitis) due to consumption of unsafe water.

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Droughts have both immediate and long-term disastrous impacts. Planning for drought mitigation requires addressing both aspects.

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Mitigation Measures:

• **Immediate Steps:** Provision of safe drinking water, medical aid, fodder and water for cattle, and facilitating the relocation of people and livestock to safer areas.
• **Long-Term Measures:**
  • Identifying and developing groundwater potential (aquifers).
  • Transferring water from surplus river basins to deficit areas (e.g., inter-linking of rivers, constructing reservoirs and dams). Remote sensing and satellite data are useful for identifying potential linkages and groundwater sources.
  • Promoting the cultivation of **drought-resistant crops** and providing training to farmers on appropriate agricultural practices for arid and semi-arid regions.
  • Implementing **rainwater harvesting** techniques, such as rooftop rainwater harvesting, to collect and store water for domestic use and groundwater recharge.

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Landslides

A **landslide** is the rapid downslope movement of a mass of rock, debris, or earth. While individual landslides might be less dramatic than a major earthquake or tsunami, their cumulative impact on the natural environment, infrastructure, and national economy can be significant, often disrupting transportation routes (like blocking highways or railway lines - Figure 6.9). (This refers to Figure 6.9).

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Unlike some other large-scale disasters, landslides are often triggered by highly **localized factors**, such as slope steepness, geological structure, soil type, vegetation cover, rainfall intensity, and human activities. This localized nature makes predicting the exact timing and location of landslides difficult and expensive.

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Based on past occurrences, geological factors, slope characteristics, and human activity, areas in India can be classified into different landslide vulnerability zones.

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Landslide Vulnerability Zones

India is divided into zones indicating the likelihood of landslides:

• **Very High Vulnerability Zone:** Includes highly unstable, geologically young mountainous regions (Himalayas, Andaman & Nicobar Islands), areas with steep slopes and heavy rainfall (parts of Western Ghats, Nilgiris, Northeast), regions experiencing frequent earthquakes (which can trigger landslides), and areas with intense human activities like road construction, dam building, or mining.
• **High Vulnerability Zone:** Areas with similar conditions to the very high vulnerability zone, but perhaps with less intense or frequent triggering factors. Most Himalayan states and states in the Northeast (excluding the plains) fall into this category.
• **Moderate to Low Vulnerability Zone:** Regions with less precipitation (Trans-Himalayan areas like Ladakh, Spiti), or areas with stable relief and low rainfall (Aravallis, rain shadow areas of Western and Eastern Ghats, Deccan plateau) still experience occasional landslides, often triggered by heavy rainfall events or localized factors. Landslides due to mining and subsidence are more common in plateau states like Jharkhand, Odisha, Chhattisgarh, Madhya Pradesh, Maharashtra, Andhra Pradesh, Karnataka, Tamil Nadu, Goa, and Kerala.
• **Other Areas (Relatively Safe):** Remaining parts of India, such as the plains of Rajasthan, Haryana, Uttar Pradesh, Bihar, West Bengal (except Darjiling), Assam (except Karbi Anglong), and coastal regions of the southern states, are generally considered safe from landslides.

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Consequences Of Landslides

While the area directly affected by a single landslide may be localized, the consequences can be far-reaching:

• Blocking of roads, railway lines, and transportation networks, disrupting movement and economic activity.
• Channel-blocking of rivers due to rockfalls or debris accumulation, leading to the formation of temporary lakes that can breach and cause downstream floods.
• Destruction of property and loss of life if settlements are located in the path of a landslide.
• Increased risk and cost of spatial interaction (travel and transport) in landslide-prone areas, hindering developmental activities.

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Mitigation

Effective landslide mitigation requires area-specific measures and a combination of structural and non-structural approaches:

• **Restrict Development:** Limiting construction activities (roads, dams, buildings) in high-vulnerability zones. Discouraging agriculture on steep slopes. Avoiding large settlements in high-risk areas.
• **Positive Actions:** Promoting large-scale **afforestation** and vegetation cover on vulnerable slopes to stabilize soil. Constructing **bunds** and drainage systems to control water flow and reduce erosion on slopes.
• **Terrace Farming:** Encouraging terrace farming (cutting slopes into flat steps) in hilly areas, particularly where shifting cultivation is practiced in the Northeast, to reduce soil erosion and increase stability.
• **Early Warning Systems and Monitoring:** In critical areas, monitoring slope stability and rainfall, and implementing early warning systems if possible, although this is technically challenging for localized events.

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Disaster Management

Disaster management is the process of preparing for, responding to, and recovering from disasters. It involves a cycle of activities before, during, and after an event. The Disaster Management Bill, 2005 in India provides the legal framework for this process. It defines a disaster broadly, recognizing that it overwhelms local coping capacity.

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Answer:

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Disaster management involves three main stages:

• **Pre-disaster management:** Actions taken before a disaster occurs to minimize risk and prepare for response. This includes hazard identification, vulnerability assessment, creating vulnerability zoning maps, collecting data and information, public awareness campaigns, developing disaster plans, preparedness measures (like drills, stockpiling supplies), and implementing preventive measures (like building codes, land-use planning).
• **During disasters:** Immediate actions taken during and immediately after an event to save lives and minimize further harm. This includes emergency response operations such as search and rescue, evacuation of affected populations, setting up temporary shelters and relief camps, and providing essential supplies (water, food, clothing, medical aid).
• **Post-disaster operations:** Activities aimed at recovery and rebuilding after a disaster. This involves rehabilitation of victims (providing temporary housing, support), recovery efforts (restoring infrastructure, livelihoods), and crucial capacity-building activities to learn lessons from the disaster and improve preparedness and response for future events.

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For a country like India, where a large portion of the population and area are vulnerable to various disasters, effective disaster management is vital. Initiatives like the Disaster Management Bill, 2005, and the National Institute of Disaster Management are positive steps towards strengthening the country's capacity to deal with disasters. While natural disasters cannot be eliminated, focusing on proactive mitigation and preparedness strategies can significantly reduce their impact and build resilience in vulnerable communities.

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Conclusion

Disasters, whether caused by natural forces or human actions, are unwelcome events that can result in significant harm and disruption. While not every natural hazard necessarily escalates into a disaster (depending on vulnerability and coping capacity), it is difficult, if not impossible, to prevent the occurrence of natural hazards themselves.

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Therefore, the most effective approach is to focus on **disaster mitigation** (reducing the potential impact of hazards) and **disaster preparedness** (being ready to respond effectively when an event occurs). Disaster management is a continuous process involving stages before, during, and after a disaster, aimed at reducing vulnerability, enhancing response capabilities, and promoting recovery and resilience.

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Acknowledging that some developmental activities can inadvertently increase disaster risk, sustainable development practices are crucial. The increasing frequency and intensity of disasters globally highlight the need for a proactive, integrated, and community-centered approach to disaster management, building on international cooperation and national policy frameworks.

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Exercises

Multiple Choice Questions

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Answer The Following Questions In Less Than 30 Words

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Answer The Following Questions In Not More Than 125 Words

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Project/Activity

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