Unit 1 - 1.1 & 1.2 Hazards and Disasters PDF

# Unit I ## Introduction to Hazards and Disasters ### 1.1 Meaning, Types and Nature of Natural and Man-made Disasters: An Introduction Any event, whether natural or man-made, occurring within the Earth or Earth's surface or from the atmosphere or from water resources, which results in great damage...

# Unit I ## Introduction to Hazards and Disasters ### 1.1 Meaning, Types and Nature of Natural and Man-made Disasters: An Introduction Any event, whether natural or man-made, occurring within the Earth or Earth's surface or from the atmosphere or from water resources, which results in great damage to biological communities is termed as disaster. Hazards are generally processes which cause an extreme event* or danger. Therefore, hazards are processes of genesis of extreme events whereas disasters are responses or results of hazards. Hazardous environments create extreme events, but all extreme events are not disastrous, rather they become disasters when they hit inhabited areas. The word disaster is derived from a French word "desastre," which is an amalgam of two words "des" meaning evil or bad and "astre" meaning a star. Thus, the word disaster signifies bad star. As stated by United Nations Office for Disaster Risk Reduction (UNISDR), a disaster can be defined as "a serious disruption of the functioning of a community or society involving widespread human, material, economic, or environmental losses and impacts, which exceeds the ability of the affected community or society to cope with using its own resources." **\*extreme events**: events or accidents, can be man-made or natural, which occur very rarely and aggravate natural processes. ### 1.2 Characteristics, Causes and General Effects of Disasters Disasters, whether natural or anthropogenic, have devastating effects on the environment. They occur indiscriminately. A hazard becomes a disaster when it hits an inhabited area. The following are characteristic features of disasters: 1. Disasters can be natural or man-made hazards. 2. Disasters can occur instantaneously or slowly, but they occur without discrimination. 3. It is people who matter most, and without people, we have no disaster. 4. The quantum of disaster is measured in terms of damage done to human society. 5. All the hazards are not disastrous; they become disasters when they strike an inhabited area. For example, a cyclone is a hazard when it occurs and dies in the midst of an ocean, but it becomes a disaster when it strikes inhabited coastal areas causing colossal loss to life and property. 6. Disasters disrupt the social structure and impair life-supporting systems. 7. They cause socio-economic problems, health issues, and infrastructural damages. #### Causes: Discussed in 1.1 Even before industrialization, natural disasters have been a fact of life. But the ever-increasing world population has increased the intensity and frequency of disaster both at national and international levels. This has led to life-altering impact in the lives of humans. 1. **Individual Impact**: The impact can be felt physically, mentally, and emotionally. After experiencing a disaster, many individuals develop stress or go into a state of depression. The loss of resources, security, and access to shelter can lead to massive population migration. 2. **Humanitarian Crisis**: Disasters lead to large-scale migration, creating migrant populations called climate refugees or environmental migrants. They have to migrate to new places in search of shelter, food, and mental peace. Sometimes many find it difficult to adapt to new environments, developing traumatic stress. 3. **Public Health Issues**: Due to disaster, facilities for water and toilet hygiene are either damaged or inoperable. During and after events like floods, standing water can become a breeding ground for pathogenic bacteria and disease vectors like mosquitoes. Survivors cannot reach safe places due to damage in infrastructure. They can suffer mental health consequences like post-traumatic stress disorder (PTSD). 4. **Infrastructural Damage**: Disasters damage both public and private infrastructure. No country in the world is entirely safe until it has the capacity to limit the impact. 5. **Loss of Life**: It results in the loss of life of humans, plants, as well as animals. The earthquake in 2005 with an epicenter at POK caused 74,698 casualties. 6. **Economic Impact**: Disaster not only results in the loss of life, but it has an impact on wealth, too. It takes huge sums of assistance to start recovery plans. Hurricane Katrina in 2005 of New Orleans and the Mississippi Gulf Coast not only destroyed 2 lakh homes, but the US economy suffered a 2% loss of overall GDP within one year of the disaster. 7. **Environmental Problems**: Disasters cause wide-ranging and long-term consequences for ecosystems, releasing pollutants or radioactive waste, thus demolishing the habitat of living beings. The Fukushima Daiichi Nuclear Disaster (2011) resulted in the release of radioactive material in Japan and into the Pacific Ocean. The Chernobyl Disaster caused the spreading of radioactive material to far areas. Loss of coral reefs can put coastal regions in jeopardy of tidal waves and surges. 8. **Developing and Least Developed Countries**: Developing and least developed countries are most adversely affected by disasters because of least disaster preparedness and disaster response due to the lack of resources and infrastructure, poor disaster planning, laxity in enforcing safety standards, etc. The emergence of technological man has significantly modified natural processes but too much interference with nature has called upon her wrath on us. ### Environmental Hazards: Concept and Management Disasters can be classified into different types depending upon the interest and purpose of the person, society, government agencies, etc., as follows: 1. **On the basis of causative factors**: Disasters can be categorized into two: a. **Natural Disasters**: These are adverse events that occur due to natural processes. They are further divided into the following: i. **Geological Disaster**: These involve geological processes such as plate tectonics, erosion, weathering, volcanic activity, seismic activity, tsunamis, and landslides, etc. ii. **Atmospheric Disaster**: It involves atmospheric or meteorological events such as cyclones, storms/wave surges. iii. **Hydrological Disaster**: These are related to hydrological sources. Avalanches and floods are the examples. iv. **Biological Disaster**: It includes diseases, epidemics, and insect/animal plague. v. **Climatological Disaster**: Drought, wildfires, and extreme temperatures are the examples. vi. **Extra-Planctary Disaster**: It includes celestial events such as the collision of meteors with Earth, the mutual collision of meteors. b. **Man-Made/Induced Disaster**: These are events which occur due to human activities. They are further divided into: 1. **Physical Disasters**: These disasters change the physical features of Earth. For example, reservoir-induced seismic (RIC) disaster, man-induced landslide, accelerated soil erosion, etc. 2. **Chemical Disasters**: It is the release of hazardous substances into the environment. For example, release of toxic chemicals, nuclear tests, and explosions, large-scale leakage of petroleum from oil tankers, etc. 3. **Biological and Health-related Disasters**: It occurs due to exposure of living organisms to germs and an increase in the concentration of toxic microorganisms. For instance, epidemics and pandemics, eutrophication, insect swarms, etc. 4. **Technological Disasters**: These occur due to technological failure or due to the misuse of technology. For example, the failure of nuclear plants, nuclear wars, accidents, etc. 2. **On the basis of rate of occurrence**: Some disasters occur very rapidly and inflict heavy loss to the human population and property, whereas some occur very slowly and last for a longer duration causing damage to life and property. They are categorized into: a. **Sudden and Rapid Onset Disasters**: They include earthquakes, tsunamis, volcanic eruptions, landslides, tornadoes, etc. b. **Slow Onset Disasters**: They include drought, entroplication, desert spread, environmental degradation, etc. 3. **Compound Disasters**: When one type of hazard triggers other hazards, resulting in a combined effect of those hazards. It causes more devastation and more misery. For example, incessant rainfall in hilly areas triggers massive landslides and slope failures. Earthquakes trigger tsunamis. Compound disasters can occur at the same time or in a sequence (Fig. 1.1). **** ## Disasters | **Natural** | **Man-made** | |---|---| | Geological | Physical | | Atmosphere | Chemical | | Hydrological | Biological and Health Related | | Biological | Technological | | Climatological | | | Extra-Planetary | | ## Compound Disasters **Fig 1.1: Classification of Disasters**