Dangers And Destructions Of Floods And Hurricanes Essay, Research Paper
Dangers and Destructions of Floods and Hurricanes
Floods and hurricanes have been effecting the lives of people around
the world for years. This research paper is going to state some of the worst
floods and hurricanes, and how future ones can be controlled.
A flood is an overflow of water on dry land. The two types of floods
are coastal and river floods. Coastal floods are the first topic in this
research 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 coastal
currents. Coastal floods can cover a large amount of distance along a shore. The
length of time a coastal flood is dangerous is usually very short. It depends on
how high the tide is which goes up and down twice a day. When the velocities of
hurricane winds become severe the height of the waves become three or more feet
higher than the previous high tide. Coastal floods can be caused by a number of
things. Coastal floods can be caused by runoff, hurricane waves, tsunami
(seismic sea waves), and hurricane rains. Coastal flooding can not only take
part on oceans but it can also take part on lakes. Coastal flooding can be a
great danger because coast lines are very densely populated areas. In the United
States in the early 1990’s 50% of the population was on a coastal county.1
Although they shrink before reaching shore, wind generated waves have been
spotted to be as high as 30 m (100 ft) in the middle of the ocean.2 In 1970 a
major storm in the Bay of Bengal produced heavy seas that flooded regions of
East Pakistan, killing about 200,000 people.3
River flooding can happen a number of ways. The causes are rain,
snowmelt, and ice jams. Soil can not absorb as much water with continuos
moistening. The longer that precipitation lasts the more water flows into
streams as runoff. Cloudburst floods only last for a couple hours, but they need
a large amount of rainfall. This usually only happens in mountainous areas. They
are called flash floods. Floods occurring from snowmelt and ice jams do not have
to be preceded by heavy rains. Moderate amounts of rain can make things even
worse because the ground does not absorb it. Floods can result in the failure
dams, aqueducts, weirs, landfills, paving, construction, and storm sewers. They
are artificial causes.
In 1993 when rainfall lasted from April until July in Iowa, Illinois,
Minnesota, Missouri, Wisconsin, South Dakota, Nebraska, and Kansas, it covered
about 16 billion acres.4 Many deaths and $10 billion in damage was the result
flood level records.5 In March of 1936 snowmelt equaling 10-30 in. of rain
occurred in New England.6107 people died and $270 million in damage was done.7
In 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 was
done.8 In January of 1995 18 counties and several parts of Calif. were declared
disaster areas by President Clinton and 1,000 shelters were opened.9 A 21 year
old Californian surfer watched his house be flooded, but on the bright side the
waves should be good tomorrow. People have paddled past gas stations and are
eating hot dogs and marshmallows for supper. Here is a table concerning the
rainfall of California in January of 1994.
L.A. 7.36 in. .67 in. (average)
San Francisco 5.28 in. 1.40 in. ”
Sacramento 6.60 in. 1.10 in. ”
Redding 9.39 in. 1.50 in. ”
National Weather Service Com. California Department of Water Resources.10
The averages for deaths and damages since 1970 from floods is 200
deaths and $4 billion in damage.11 It would be much higher if it wasn’t for the
National Weather Service River and Flooding Forecasting Service. The National
Weather Service River and Flooding Forecasting Service gives flood watches and
flood warnings to the civilians. The forecasting of floods are based on
Meteorologists, upstream information, and how different places respond to
precipitation. The United States Coast and Geologic Survey monitors seismic
waves and tides in the Pacific Ocean. It is said to have saved many lives. Flood
analysts can measure the probability of floods of various sizes. If a flood has
a 1 in 100 chance of being equaled it is called a 100 – year flood.12
Where major flooding happens once a year, the need for land is
larger than the dangers of flooding. In 1985 the Delta Plan was completed. It is
9 km. of steel gates suspended between 66concrete pillars on the Delta River.13
The Thames River has a similar construction. It was completed in 1982. Examples
of structural flood control are dams, reservoirs, levees, dikes, stream channels,
flood-diversion systems, and watershields. Dams control and impound water at
times of flood and release when the flood is over. Artificial levees raise the
heights of stream banks. This can often fail. Straightening flood channels
allows water to flow faster and shallower. It is often temporary. The
nonstructural approach is simply preventing building in a floodplain. The
National Flood Insurance Act provides insurance for communities in flood prone
areas.
By definition a hurricane is a violent storm with winds over 75
miles per hour. A hurricane is much more than that. A hurricane is a storm and
also a disaster that includes many deaths and expensive damages. A hurricane is
something that can not be described in this paper. Some say a hurricane can be
summed up in two words “Death Storm”.
A hurricane is the name applied to migratory tropical cyclones that
originate over oceans in certain regions near the equator, and particularly to
those arising in the West Indian region, including the Caribbean Sea and the
Gulf of Mexico.
Most hurricanes originate within the doldrums, a narrow equatorial
belt characterized by intermittent calms, light variable breezes, and frequent
squalls, and lying between the northeast and southeast trade winds. As the
doldrums of the Atlantic are situated largely to the north of the equator,
hurricanes do not occur in the South Atlantic Ocean. The Pacific doldrums extend
north and south of the equator; thus hurricanes occur in the south and north
Pacific Oceans.
Hurricanes generally move in a path resembling the curve of a
parabola. In the northern hemisphere the storms usually travel first in a north
westerly direction and in the higher latitudes turn toward the northeast. In the
southern hemisphere the usual path of the hurricane is initially to the
southwest 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 higher
latitudes it may increase to as much as 80 km/hr. Those areas in which the
hurricane winds blow in the same direction as the general movement of the storm
are subjected to the maximum destructive violence of the hurricane.
Hurricane Emily packed winds around 80 miles per hour and was a
level 3.14 Hurricane Emily’s gale force winds hit North Carolina at 39 miles per
hour, but that was all.15 Emily brought 115 miles per hour winds and heavy rains
to the Outer Banks in 1993. It dumped 4 to 8 in. of rain.16 Hurricane Hugo
packed 135 miles per hour winds and killed 21.17 It was the worst in 35 years to
hit Charleston, South Carolina. It killed tourism instantly but temporarily.
Most hurricanes reach velocities of 100 to 180 miles per hour, and a
radius of 6 to 60 mi. Hurricanes could have a diameter of up to 2,000 mi.18 That
is a very large one. The eye has light winds of up to 6 and60 miler per hour. It
has minimum surface pressure.19
Hurricanes use to be detected by land reports. Now they can be
detected by air. Hurricanes started to get their names in 1953 by the United
States Weather Service. The National Hurricane Center can predict hurricanes by
using models. Professionals can track a hurricane in 20 minutes and error free
within 48 miles.20 By hurricane season of 1996 a 36 hour forecast should be as
accurate as a 24 hour forecast was 2 years ago.21
That concludes my research paper on floods and hurricanes. This
paper tried to show you how dangerous and how horrible the natural disasters
really are. Floods and hurricanes cause nothing but turmoil anywhere they happen.
This paper states that floods and hurricanes are as dangerous now as ever, but
thankfully they are being controlled more and more each year.