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“Natural Disaster, its causes & effects.”

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“Natural Disaster, its causes & effects.”

  1. 1. Assignment on – “Natural Disaster, its causes & effects.” 1
  2. 2. Introduction of Natural Disaster: A natural disaster is a disaster caused by nature, such as floods, volcanic eruptions, earthquakes, tsunamis, avalanches, lahars (volcanic mudslides), landslides, sinkholes, blizzards, drought, hailstorms, heat waves, hurricanes, tropical storms, typhoons, Ice Ages, tornadoes, and wildfires. Epidemics caused by bacteria or viruses are sometimes considered natural disasters, but sometimes put into a different category. A biological threat such as locusts or toxic fungi could also be considered a natural disaster. Some disasters are on the edge of natural and non-natural. Famines, the chronic lack of food, may be caused by a combination of natural and human factors. Two space-originating categories of natural disaster, both of which rarely effect humans on the surface, include asteroid impacts and solar flares. Although the risk of asteroid impact in the short term may be low, some scientists argue that in the long term, the likelihood of death by asteroid is similar to that of death by traditional natural disasters such as disease. The deadliest natural disasters are famines, which claimed 70 million people during the 20th century alone, with 30 million dying during the famine of 1958–61 in China. In the Soviet Union there were several man-made famines that killed millions, blamed on the collectivist policies of Stalin, the leader of the country at the time. Famines have a history of bringing out the worst in people, including atrocities and cannibalism. Another of the deadliest natural disasters is epidemics, most notably the Spanish flu of 1918-1919, which killed 50 million — more than World War I, which had occurred just before. Rather than killing infants or the aged, the Spanish flu struck down people in the prime of life. Having a good immune system was no protection against this virus — in fact, it was a liability. The virus is believed to have killed its victims primarily through over activating the immune system in a process called a cytokine storm. Historically, volcanoes may have been the biggest type of natural disaster. Some scientists believe that the eruption of Mt. Toba in Indonesia over 73,000 years ago may have killed off most of the human species, leaving behind only 1,000 - 10,000 breeding pairs. This phenomenon, called a population bottleneck, has been confirmed through genetic analysis. 2
  3. 3. Definition of Natural Disaster: A natural disaster is the effect of earth’s natural hazards, for example flood, tornado, hurricane, volcanic eruption, earthquake, heat wave, or landslide. They can lead to financial, environmental or human losses. The resulting loss depends on the vulnerability of the affected population to resist the hazard, also called their resilience. If these disasters continue it would be a great danger for the earth. This understanding is concentrated in the formulation: "disasters occur when hazards meet vulnerability."[Thus a natural hazard will not result in a natural disaster in areas without vulnerability, e.g. strong earthquakes in uninhabited areas. The term natural has consequently been disputed because the events simply are not hazards or disasters without human involvement. A concrete example of the division between a natural hazard and a natural disaster is that the 1906 San Francisco earthquake was a disaster, whereas earthquakes are a hazard. This article gives an introduction to notable natural disasters; refer to the list of natural disasters for a comprehensive listing. Natural disasters are cataclysmic events that can have a direct or indirect impact on the public's health and well-being, according to the United States Department of Health and Human Services. Natural disasters can include weather phenomena as well as landslides and avalanches, which occur as a result of erosion or severe weather patterns. Natural disaster of a different kind: Cold Spell in Bangladesh: Being a Bangladeshi, it is never a pleasant experience to talk about the periodic natural disasters, mainly floods and cyclones that ravage the country every now and then. To increase the sufferings of the poor disaster vulnerable people of the country, recently there has been a new addition to the list of regular natural disasters of Bangladesh named Cold Spell, thanks to the global climate change. The impact of Cold Spell is as notorious as other regular natural calamities of Bangladesh as far as the death toll is in concern. The recent Cold Spell that appeared on the 7th January in Bangladesh has already taken sixteen lives, out of which are 9 children and made most of the population of the northern Bangladesh to suffer with pneumonia, cold diarrhea, cough, fever, asthma and other cold- related diseases. 3
  4. 4. During a Cold Spell, gusty extreme cold wind coupled with heavy fog covers the whole area of Bangladesh. Historically the average winter temperature in Bangladesh is within 15 to 20 degree Celsius. However, in recent Cold Spells this average temperature has dropped to as low as 4 degree Celsius, a new record for the country. The most affected area during this calamity is the northern part of the Bangladesh which is closer to the Himalayas. Northern Bangladesh is the most poverty stricken area of the country where people have year round income poverty and seasonal food poverty during the time of agricultural lean seasons. The recent catastrophe of Cold Spell has magnified their sufferings to a severe extent, shortage of warm clothing and shelter has caused them even their lives. The sufferings of poor people of northern Bangladesh reached to an untold terrible stage especially for those who live in the remote island areas of river Tista, which is locally known as Char. Some places in the northern part had not seen the sun for the last 3 to 4 days due to the extreme fog and clouds. Most places of the char areas in the river basins remained covered with fog, reducing the visibility till noon almost every day. In such situations, poor cannot join their regular work because of the unfavorable weather condition as well as due to sickness. As a result, they lose a significant share of their regular income which further reduces their ability to take proper action against the shock. Also the daily transportation of food items from all parts of the country has been dangerously interrupted. Basic road and water transportation has been delayed for an indefinite time, causing major physical communication to an almost complete halt. Needless to say, such physical communication chaos has triggered the price of common household commodities to a seasonal extreme, causing the sufferings of the poor even more severe. People who took desperate attempt to hit the road ignoring such bad driving conditions have already paid the price with road accidents if not heavy traffic congestions in the highways. The main reason for such calamity is the constant and consistent blow of chilly wind from the northwest blowing at a speed of 10-15 kms per hour which made the weather further cooler during the typical winter season. As there is no rain, pollen count in the air is relatively high in this season making the air full of dust and causing respiratory problem and allergic infections along with asthma, pneumonia, chronic bronchitis, respiratory problem, chronic obstructive pulmonary disease. Hospitals, especially those in the northern part of the country, are experiencing 4
  5. 5. massive admission of patients suffering from cold related illnesses for the last few days. Reports received from different sources mentioned seriously sufferings of thousands and millions people living in the sandy char areas in Kurigram, Lalmonirhat, Gaibandha, Rangpur, Nilphamari, Bogra and Sirajganj districts on the Brahmaputra basin. Effects of Natural Disasters: Natural disasters have become so commonplace that they hardly receive passing notice on the news unless there have been a large number of casualties. Volcanoes, mudslides, tsunamis and floods are just a few of the ways nature strikes on a daily basis, leaving behind destruction and heartache. Humans have learned to prepare for the possibility of tornadoes, earthquakes, hurricanes and wildfires, but no amount of preparation can lessen the impact that natural disasters have on every aspect of society. Physical Destruction: The biggest visible effect of natural disasters is the physical ruin they leave behind. Homes, vehicles and personal possessions are often destroyed within a short period of time, leaving families homeless and shutting some businesses down permanently. Tornadoes destroy structures at whim, earthquakes can cause structural damage that might not be apparent at first glance, and tsunamis and floods sweep homes off their foundations. Emotional Toll: Possessions are not hard to replace, as many people keep insurance on their property and tangible goods. The emotional toll of natural disasters is much more devastating. The death of a loved one may be the worst- case scenario but it's not the only lasting emotional effect victims experience. Whole communities may be displaced, separating friends and neighbors; victims face anxiety and depression as they wonder if it could happen again. In extreme cases, they may experience post traumatic stress disorder (PTSD). Economic Concerns: According to the National Hurricane Center, Hurricane Katrina cost the U.S. $75 billion when it slammed into New Orleans in August 2005. That doesn't include 5
  6. 6. the damage caused in the Florida counties of Miami-Dade and Broward by the same storm. While destruction of this magnitude is not commonplace, even a minor storm can cause considerable damage. At the very least, the local economy must be able to absorb the cost of cleanup and repairs. Indirect Effects: While the visible effects of natural disasters are immediate and strongly felt, communities that surround ground zero can be indirectly affected by them as well. Natural disasters almost always lead to a disruption in utility services around the area impacted. This can mean life or death for those who rely on dialysis or oxygen to live. Medical assistance is also often slowed, as emergency crews must focus on the victims of the disaster. Banks and other businesses might be closed, affecting a family's ability to withdraw money to pay bills and buy groceries. Geography: Geography plays a large role in how natural disasters affect an area. In rural or isolated communities, natural disasters can thrust families into a situation where they must do without modern conveniences like electric and running water. They may not be able to get to town to buy necessities and have to rely on what they have stocked up. Densely populated areas face their own unique problems from natural disasters. Hygiene becomes a concern, as people crowd into temporary relief centers and competes for limited resources. Environment: Humans aren't the only living things affected by natural disasters. As is the case with humans, animals can be displaced from their homes. Sometimes they have no alternative but to leave the area and try to fit into a new habitat. Volcanoes, earthquakes, floods, wildfires and mudslides often permanently alter an area's Landscape, leading in some cases to the destruction of a local species Disruption of Utilities Communities that surround areas affected by natural disasters are seriously affected by the disruption caused to utility services. Generally, power is the first thing to go when there's a natural disaster. This can literally mean life or death to the people who are on life support systems such as oxygen and dialysis. Medical assistance becomes hard to get since the crews are busy helping the victims of the disaster. Banks can be shut down, causing a shortage of cash circulation that 6
  7. 7. prevents people from accessing funds for much needed provisions for babies and small children. Emotional Damage When a natural disaster strikes, the emotional toll on the people affected is quite devastating. While possessions can be replaced eventually through insurance, the emotional damage can take a long while to heal. People lose loved ones in natural disasters; deaths of people and precious pets, serious injury and people missing all add up to severe emotional trauma. Communities get displaced meaning separation from family and friends. Victims face stress, trauma, anxiety and depression as a result of natural disasters. Social Consequences The social consequences of natural disasters in the short and long term are wide ranging. The disasters affect housing; people are left homeless and rebuilding a home takes a long time and a lot of money. Health care infrastructure is affected; the impacts are worse in developing countries that already have poor facilities to begin with. Disease starts spreading and, without proper medical attention, makes a bad situation worse. Education is a big loser when a natural disaster happens, schools are often closed, teachers are unable to come in to work and children are displaced and unable to attend school. Transportation capacity is reduced hindering relief efforts and disrupting normal life.  What Are the Different Types of Natural Disasters?  Tornado A tornado occurs on the surface of the earth's land as a result of humidity in the lower atmosphere combining with wind shears. The spinning comes by way of downdrafts and updrafts, but the violent speed is usually due to rapid changes in the air (such as dry air suddenly becoming very cool). When air mass is unstable and storms come through an area, a tornado often results. The reason most tornadoes occur in the Midwest of the United States is because tropical winds from the south Gulf move up to meet the cool winds of Canada's north. When they collide in the middle, it's usually somewhere around Kansas or Nebraska (though tornadoes can occur anywhere if the conditions are right, they're usually not as severe in other regions). 7
  8. 8.  Earthquake Violent tremors of the earth's surface are the result of earthquakes, which are caused by the shifting of the earth's tectonic plates and fault lines below the surface. When the earth's temperature changes, this causes movement of rock and plates in the earth's mantle. This happens all over the globe, but some stresses are more severe in some areas. Parts of the world that experience more earthquakes usually do so because the plates below them are more brittle and weak. In the Pacific Ocean, there is the Ring of Fire that stretches up and down the coasts of North America and South America and continues across to Japan and down to east of Australia. Volcanic eruption occurs for similar reasons, in that activity occurs below the surface of the earth causing stress and sudden release of molten rock.  Hurricane Also known as a tropical cyclone or typhoon, hurricanes are violent storms that occur off of ocean shores. High winds are produced by water that has evaporated from an ocean surface in a low pressure area. This also causes a spiraling effect, which gains momentum the more condensation it collects. Minimal hurricanes have winds of about 75 mph (Category 1), but the most catastrophic storms will blow more than 155 mph (Category 5). Once a hurricane hits land, it begins to cool and slow, but this is the point at which a hurricane does its most damage. Destruction of trees, cars and buildings is likely in the event of a hurricane.  Causes of Natural Disasters:  Floods: According to the U.S. Environmental Protection Agency (EPA), barring fire, floods are the most common natural disaster affecting Americans. Floods are a factor in 90 percent of natural disasters. Flood events have both natural and man- made causes. Storm events can create flood waters that exceed the capacity of the environment or man-made structures. Levees and dams provide a false sense of security as became evident during the Great Flood of 1993 in the Upper Mississippi River valley. A painful lesson was learned. Wetlands destruction removed a natural means to absorb floodwaters.  Fires: Fires are nature's environmental managers. They create and maintain ecosystems such as prairies and pine forests. In fact, prairies evolved with the presence of fire. The health of the ecosystem is dependent on this disturbance. Fires remove a buildup of litter on the soil surface, allowing nutrients to be released into the environment. It also creates favorable conditions for seed germination. Suppression of fire allows litter to accumulate, setting the stage for catastrophic fires. Plants and trees have adapted to the presence of fire. However, the higher temperatures of crown fires can kill plants entirely. These fires are more difficult to control. 8
  9. 9. Suppression of fires is expensive, upward of $1 billion annually, according to the U.S. Forest Service.  Drought: Drought has had more widespread effects than any other natural disaster. Each year, drought costs the United States more than $6 billion. It's safe to say that droughts have greater impacts in modern times. More people are affected by loss of land and food crops as well as environmental damage. The immediate effects are overshadowed by secondary issues. Compacted, dry soils are vulnerable to topsoil loss and erosion. Dry conditions make fires more common. Evidence suggests global warming may be the cause for an increase in drought frequency and changes in the global climate.  Weather Events: Like drought, an increase in severe weather events has been recorded in the last 100 years by the National Climatic Data Center. While notification systems are in place, vulnerabilities still exist for property damage and crop loss. Development has also complicated the effects of such events. An increase in development leads to a decrease in wetlands and an increase in impervious surfaces such as roads and driveways. This creates a scenario for floods and flash flooding. As with drought, scientists believe a link between global warming and climate changes exists.  Prevention/Solution: Not all natural disasters can be prevented. Each natural disaster has its own factors and complications. Understanding the basic principles of ecology can provide keys to lessening their effects. Nature evolved with natural disasters and disturbance. The best prevention is looking at the strategies found in nature. What Is Natural Disaster Management? Significance Effective natural disaster management saves lives. Procedures set in place before a catastrophe occurs ensure a speedier and more effective response. A preventative measure, such as strengthening the infrastructure of buildings in earthquake regions, minimizes the risk of injuries and helps people to resume normal life more quickly. Features Governments and some large corporations in developed countries designate aid money for natural disasters before they happen. They also liaise with the governments of affected regions and aid workers on the ground when a disaster occurs to determine the extent of medical aid and supplies needed. Aid workers are trained to assess the scale of the disaster. Non-government overseas aid workers may already be based in the region and have a good understanding of the local 9
  10. 10. culture, which can be invaluable in advising how to administer help effectively, according to the Global Education website. Considerations Governments and aid organizations, such as the Red Cross, and representatives of the affected region usually work together to save lives and restore order after a disaster occurs. Natural disaster management continues long after the initial crisis has passed. Funds, for example, may be allocated to rebuild homes destroyed by a flood. 10

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