Dangers and Destructions of Floods and HurricanesFloods and hurricanes have been effecting the lives of people aroundthe world for years. This research paper is going to state some of the worstfloods and hurricanes, and how future ones can be controlled.A flood is an overflow of water on dry land. The two types of floodsare coastal and river floods. Coastal floods are the first topic in thisresearch paper.A coastal flood is the flooding of beaches and surrounding areas;including bar spits and deltas. They can be effected by tidal waves and coastalcurrents.
Coastal floods can cover a large amount of distance along a shore. Thelength of time a coastal flood is dangerous is usually very short. It depends onhow high the tide is which goes up and down twice a day. When the velocities ofhurricane winds become severe the height of the waves become three or more feethigher than the previous high tide. Coastal floods can be caused by a number ofthings. Coastal floods can be caused by runoff, hurricane waves, tsunami(seismic sea waves), and hurricane rains.
Coastal flooding can not only takepart on oceans but it can also take part on lakes. Coastal flooding can be agreat danger because coast lines are very densely populated areas. In the UnitedStates in the early 1990’s 50% of the population was on a coastal county.1Although they shrink before reaching shore, wind generated waves have beenspotted to be as high as 30 m (100 ft) in the middle of the ocean.2 In 1970 amajor storm in the Bay of Bengal produced heavy seas that flooded regions ofEast Pakistan, killing about 200,000 people.
3River flooding can happen a number of ways. The causes are rain,snowmelt, and ice jams. Soil can not absorb as much water with continuosmoistening. The longer that precipitation lasts the more water flows intostreams as runoff. Cloudburst floods only last for a couple hours, but they needa large amount of rainfall.
This usually only happens in mountainous areas. Theyare called flash floods. Floods occurring from snowmelt and ice jams do not haveto be preceded by heavy rains. Moderate amounts of rain can make things evenworse because the ground does not absorb it. Floods can result in the failuredams, aqueducts, weirs, landfills, paving, construction, and storm sewers. Theyare artificial causes.In 1993 when rainfall lasted from April until July in Iowa, Illinois,Minnesota, Missouri, Wisconsin, South Dakota, Nebraska, and Kansas, it coveredabout 16 billion acres.4 Many deaths and $10 billion in damage was the resultflood level records.
5 In March of 1936 snowmelt equaling 10-30 in. of rainoccurred in New England.6107 people died and $270 million in damage was done.7In 1972 at Logan County, West Va. a dam collapsed following three days of rain.
In less than four hours 118 lives had been taken and $65 million in damages wasdone.8 In January of 1995 18 counties and several parts of Calif. were declareddisaster areas by President Clinton and 1,000 shelters were opened.9 A 21 yearold Californian surfer watched his house be flooded, but on the bright side thewaves should be good tomorrow. People have paddled past gas stations and areeating hot dogs and marshmallows for supper.
Here is a table concerning therainfall of California in January of 1994.L.A.
7.36 in..67 in.
(average)San Francisco5.28 in.1.40 in.”Sacramento6.
60 in.1.10 in.”Redding9.39 in.1.50 in.
“National Weather Service Com. California Department of Water Resources.10The averages for deaths and damages since 1970 from floods is 200deaths and $4 billion in damage.11 It would be much higher if it wasn’t for theNational Weather Service River and Flooding Forecasting Service.
The NationalWeather Service River and Flooding Forecasting Service gives flood watches andflood warnings to the civilians. The forecasting of floods are based onMeteorologists, upstream information, and how different places respond toprecipitation. The United States Coast and Geologic Survey monitors seismicwaves and tides in the Pacific Ocean. It is said to have saved many lives. Floodanalysts can measure the probability of floods of various sizes.
If a flood hasa 1 in 100 chance of being equaled it is called a 100 – year flood.12Where major flooding happens once a year, the need for land islarger than the dangers of flooding. In 1985 the Delta Plan was completed. It is9 km. of steel gates suspended between 66concrete pillars on the Delta River.13The Thames River has a similar construction. It was completed in 1982.
Examplesof structural flood control are dams, reservoirs, levees, dikes, stream channels,flood-diversion systems, and watershields. Dams control and impound water attimes of flood and release when the flood is over. Artificial levees raise theheights of stream banks. This can often fail. Straightening flood channelsallows water to flow faster and shallower. It is often temporary. Thenonstructural approach is simply preventing building in a floodplain.
TheNational Flood Insurance Act provides insurance for communities in flood proneareas.By definition a hurricane is a violent storm with winds over 75miles per hour. A hurricane is much more than that. A hurricane is a storm andalso a disaster that includes many deaths and expensive damages. A hurricane issomething that can not be described in this paper. Some say a hurricane can besummed up in two words “Death Storm”.A hurricane is the name applied to migratory tropical cyclones thatoriginate over oceans in certain regions near the equator, and particularly tothose arising in the West Indian region, including the Caribbean Sea and theGulf of Mexico.
Most hurricanes originate within the doldrums, a narrow equatorialbelt characterized by intermittent calms, light variable breezes, and frequentsqualls, and lying between the northeast and southeast trade winds. As thedoldrums of the Atlantic are situated largely to the north of the equator,hurricanes do not occur in the South Atlantic Ocean. The Pacific doldrums extendnorth and south of the equator; thus hurricanes occur in the south and northPacific Oceans.Hurricanes generally move in a path resembling the curve of aparabola. In the northern hemisphere the storms usually travel first in a northwesterly direction and in the higher latitudes turn toward the northeast. In thesouthern hemisphere the usual path of the hurricane is initially to thesouthwest and subsequently to the southeast.
Hurricanes travel at varying rates.In the lower latitudes the rate ranges from 8 to 32 km/hr and in the higherlatitudes it may increase to as much as 80 km/hr. Those areas in which thehurricane winds blow in the same direction as the general movement of the stormare subjected to the maximum destructive violence of the hurricane.Hurricane Emily packed winds around 80 miles per hour and was alevel 3.
14 Hurricane Emily’s gale force winds hit North Carolina at 39 miles perhour, but that was all.15 Emily brought 115 miles per hour winds and heavy rainsto the Outer Banks in 1993. It dumped 4 to 8 in. of rain.16 Hurricane Hugopacked 135 miles per hour winds and killed 21.17 It was the worst in 35 years tohit Charleston, South Carolina.
It killed tourism instantly but temporarily.Most hurricanes reach velocities of 100 to 180 miles per hour, and aradius of 6 to 60 mi. Hurricanes could have a diameter of up to 2,000 mi.18 Thatis a very large one.
The eye has light winds of up to 6 and60 miler per hour. Ithas minimum surface pressure.19Hurricanes use to be detected by land reports. Now they can bedetected by air. Hurricanes started to get their names in 1953 by the UnitedStates Weather Service. The National Hurricane Center can predict hurricanes byusing models.
Professionals can track a hurricane in 20 minutes and error freewithin 48 miles.20 By hurricane season of 1996 a 36 hour forecast should be asaccurate as a 24 hour forecast was 2 years ago.21That concludes my research paper on floods and hurricanes. Thispaper tried to show you how dangerous and how horrible the natural disastersreally are. Floods and hurricanes cause nothing but turmoil anywhere they happen.
This paper states that floods and hurricanes are as dangerous now as ever, butthankfully they are being controlled more and more each year. English