Floods Are an Overflow of Water That Essay
- Length: 3 pages
- Sources: 3
- Subject: Weather
- Type: Essay
- Paper: #30850712
Excerpt from Essay :
Floods are an overflow of water that submerges land and usually happen because of a large amount of rainfall, saturated soil, and/or the capacity of the body of water is exceeded:
Often floods are seasonal in nature, coming after Spring rains.
Floods also occur in rivers, when flow exceeds capacity in certain areas of the river channel.
Floods have impacted society for centuries because people like to live near water and water transportation.
In certain parts of the world, typically those with regular monsoon conditions, flooding is a regular seasonal issue
Suggested graphics: http://www.kidcyber.com.au/IMAGES/Floods4.jpg
Types of Floods -- The flood type depends on the geographic location of the body of water and its tendencies:
Areal flooding happens when flat, low-lying areas cannot absorb any more water
River floods occur when the river cannot carry away all the extra water and the river overflows
Coastal floods are usually caused by harsh weather blowing waves onto land.
Flash Flooding is a quick flood caused by a sudden cloudburst or thunder storm. Often these happen in mountainous areas with steep slopes.
Flooding from Human Action occurs when an artificial structure like a dam fails, or levees or pipes burst or are poorly constructed.
Suggested graphics: http://www.sciencemediacentre.co.nz/wp-content/upload/2011/02/flood.jpg
Flood Causation -- Flood can occur for a number of reasons, which makes them incredibly hard to predict and prepare for, particularly since humans tend to congregate around water.
Water from storms can no longer be absorbed into the soil; either pools or runs to lower elevation.
Heavy snowfall pack in areas followed by strong Spring/Summer rains
Intense precipitation -- thunderstorms, etc. Or release from a landslide or glacier
In estuaries caused by tidal surges from storm-force winds
Tsunami's or hurricanes -- storm surges
Catastrophic from dam breakage, earthquake or volcanic eruption -- also called outburst flooding
Suggested graphics: http://www.cnn.com/video/weather/2011/01/12/vo.sri.lanka.floods.slrc.640x360.jpg
Effects of Flooding, Part 1
Primary effects -- damage to structures, bridges, buildings, sewage system, roadways, canals
Floods have had a major impact on human society for centuries
Floods disrupt society completely; including social structures and economics
Transportation issues affect surrounding areas
People may need to be evacuated and rehoused for a time
Disruption in entire socio-culture template
Suggested graphics: http://news.xinhuanet.com/english/2008-06/15/xin_5020605152044156235937.jpg
Effects of Flooding, Part 2
Secondary effects -- as the water recedes or damage due to pressure, weather, etc.
Secondary effects may last for months, even years
Water supplies -- water may become contaminated
Potable water becomes rare
Spread of waterborne diseases (lack of sanitation, standing water)
Crops and food supplies ruined, sometimes entire harvests
Forest and land -- many trees die from suffocation
Transport links are down, hard to supply emergency aid
Suggested graphics: http://si.wsj.net/public/resources/images/WO-AH656_THAIFL_G_20111103200730.jpg
Effects of Flooding, Part 3
Long-term effects can devastate a region
Economic hardship due to decline in tourism, insurance and building costs, food shortages, price increases, lack of work, displacement of people
Psychological -- traumatic from death, injury, displacement, lack of support, loss of property, and complete life-change occur
Suggested graphics: http://1.bp.blogspot.com/_nMLR3Feb9RM/TUe8wRAOj0I/AAAAAAAAG7I/PkbF5ZVn9ow/s1600/pakistanfloodsAP
Floods caused by global warming
Some studies show that global warming and changes in weather patterns increase the likelihood of flooding
Increased precipitation in some areas can be one result of polar or glacier melts
Warm air holds more moisture, making outbreaks of heavier than usual rainfall more frequent, particularly in areas that are not flood prone
Some scholars think that the 2000 Floods in Britain were cause by climate change conditions.
Suggested graphic - http://i.telegraph.co.uk/multimedia/archive/01827/Floods2_1827722b.jpg
Floods and Urban Planning
Increased urbanization, particularly in poor countries, without adequate building codes
Lack of storm drainage facilities or outmoded and poorly constructed facilities
Inadequate construction of levees, dykes, etc. (e.g. Katrina)
Inadequate disaster planning and evacuation procedures
Suggested graphic - http://cdn.punchng.com/wp-content/uploads/2012/06/Lagos-flood.jpg
Flood Control, Part 1
Humans have been trying to control floods for thousands of years. However, some flooding, particularly along the great river valleys (e.g. Nile) were the reason agricultural activities flourished and civilization developed
There is a balance between the regular flooding of river areas and catastrophic flooding
Suggested graphic - http://t1.gstatic.com/images?q=tbn:ANd9GcR8qfhdv0UvHzxKQsI8D1gJ06Ec72uZAtyhZzjc8VhjQb9k80MQ8z2n0mGv
Flood Control, Part 2
Dams and reservoirs are designed to aid in flood protection and control. They do this by controlling water levels and allowing water to flow as needed, but to protect lower elevations by storing water behind the dam wall.
River defenses -- Levees, bunds, reservoirs and weirs (low head dam) are all used to…