Wednesday, October 13, 2010

Natural Hazard by Mary Garcia

Environmental Studies
Dr. David Terrell
Warner Pacific College
October 9th, 2010

Natural Hazards come in many forms, shapes and sizes. Some forms are fairly common and have been experienced world wide; others have only been read about or viewed on local news stations as happening to someone else. Where do natural hazards come from, how devastating can they be, are we as a society prepared in the event of a natural hazard? In order to be prepared we must first understand what a natural hazard is.
A natural geological hazard may include debris avalanches, landslides, rock falls or expansive soils, while a natural hydrologic hazard may come in the form of coastal flooding, desertification, drought, submarine slides, storm surges, salinization, erosion or river flooding. A natural atmospheric hazard may come in the form of a hailstorm, hurricane, lightening, tornadoes or even a tropical storm.
Volcanoes are commonly known, but due to their inconsistent activity are mistakenly not viewed as a threat, but lava and pyroclastic flows followed by the ashes and cinders (commonly known and tephra) from projectile blasts, followed by emanating gases are quite lethal and can cause massive devastation in a short period of time. Seismic activity is another form of a natural hazard.
Quite consistent are the moving platelets of the earth’s structure causing earthquakes and tsunamis, fault ruptures and lateral spreading. Brush, forest, grass and savannah fires are all categorized as wildfires and are just another form of a natural hazard.
These are all elements of a physical surrounding environment that has the potential to be harmful to a society and that which a society has no control over and because of the hazards frequency, location and possible severity it has the potential to adversely affect the structures and activities of a society (Burton, Kates & White, 1978).
The Natural Hazards Project (1990) asks the question “how natural is a natural hazard?” According to the Natural Hazards Project of the Department of Regional Development and Environment, “a natural hazard has an element of human involvement.” The text explains that a physical event that does not affect society is known as a natural phenomenon, while a natural phenomenon that may occur within a populated area (such as a volcanic eruption) is considered to be a hazardous event and when that event causes large numbers of injuries, fatalities or property damage it is then considered a natural disaster. “In areas where there are no human interests, natural phenomena do not constitute hazards; this definition shifts the burden of cause from purely natural processes to the concurrent presence of human activities and natural events.” (Natural Hazards Project, 1990).
To gage society’s vulnerability to a natural disaster occurrence, society must first consider certain elements of a natural disaster, such as the rapid or slow movement of the occurrence and how controllable the events are. What is the frequency of the occurrence and how severe will it be. Can our society withstand or even avoid the impact of the occurrence.
The speed with which a hazard occurs in an important variable as it forms whether or not there will be any warning time. An example of such are volcanoes, they can erupt swiftly, but generally give a warning of an eruption weeks or even months in advance. Other hazardous events such as a drought occur slowly over a period of time that could take months or even years to complete. Some types of hazards, such as year round flooding where the hazard becomes part of the landscape, allows society to build accordingly or to take specific measures to protect against it.
Grade school teaches students to duck under desks in the event of an earthquake and send home pamphlets for tips on preparing your home for a power outage, society has developed and offers the assistance of 911 for your emergency needs and the professionals trained to handle emergency situations. But what happens when emergency response teams are unable to assist? Having never experienced a natural hazard or been involved in any kind of training, my family and I are completely unprepared for an event to occur. Perhaps I will scour the map of terrains and choose to live in a spot less likely to experience any of the hazards I have described today.

References

Hays, W.W. (ed) Facing Geologic and Hydrolic Hazards, Earth-Science Considerations. (Washington, D.C., U.S. Government Printing Office, 1981)

Burton, I., Robert W. Kates ad Gilbert F. White. The Environment as Hazard (New York; Oxford University Press, 1978)

Natural Hazards Project. (1990). Retrieved from http://www.oas.org

John A. Cross. “Hazard Maps in the Classroom,” Journal of Geography (1988)

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