Megan Ortiz
Hurricane Katrina
Questions:
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7)
What is a Category 1 hurricane? Category 5?
What is the highest category of hurricanes?
How fast are hurricanes normally? Or the average speed?
What are some other Category 5 hurricanes?
Anyway to prevent costly damage of a hurricane?
Why have there been an increasing number of hurricanes since 1995?
Are recent increases in the number and strength of hurricanes evidence of global
climate change?
Effects:
E<A: Hurricanes produce high and strong wind speeds.
E<A<H: Heavy rainfall is a result
E<L<H: Large amounts of damage on the earth, landslides, as well as floods
E<B: Deaths of humans and animals, as well as homes and habitats.
Known:
-Hurricanes occur in warm tropical waters.
-High winds are produced by exchanging of heat.
-High pressure air produces high wind speeds.
-Inland flooding is a major result of hurricanes
Unknown:
-How hurricanes form
-Different types of hurricanes
-Which types of hurricanes cause the most damage?
-The effects on the climate resulted from a hurricane
A storm goes through a series of stages before being classified as a hurricane.
Thunderstorms
Tropical
with light
Disturbance cyclonic
circulation
Tropical
Wind speeds
Depression between 20
and 34 knots
(23-39 mi/hr)
Tropical
Storm
Wind speeds
between 35
and 64 knots
(40-73 mi/hr)
Hurricane
Wind speed
greater than
64 knots (74
mi/hr)
Hurricanes Categories:
The Saffir Simpson Hurricane Scale is what is used to categorize hurricanes.
 There are 5 categories, 5 being the most extreme.
 The scale measures the speed of the wind.
Category 1 has wind speeds around 74-95mph
This category does no real damage to buildings, but there is possible
damage to mobile homes and poorly constructed signs. Coastal flooding and
minor pier damage could also occur.
Such hurricanes include: Irene 1999 and Allison 1995
Category 2 has wind speeds of 96-110mph.
There is some damage to roofs, doors and windows; flooding damages to
piers and small craft in unprotected moorings. Some trees may also blow down.
Examples are Bonnie 1998, Georges 1998 and Gloria 1985
Category 3 winds 111-130mph
Some damage to small residences and utility buildings. Large trees can be
blown down. Flooding near the coast may destroy small structures. Large
structures can be damaged by floating debris. The terrain may also be flooded
well inland.
Examples: Keith 2000, Fran 1996, Opal 195, Alicia 1983 and Betsy 1965
Katrina 2005
Category 4 winds 131-155mph
Some complete damage of roof structures on small residences; major
erosion of beach areas and terrain can also be flood well inland.
Ex: Hugo 1989 and Donna 1960
Category 5 winds 156mph and up.
Category 5 hurricanes are very rare, occurring about once every one hundred
years. However, there have been several major hurricane events along the east
coast of North America.
Complete roof destruction of many residences and industrial buildings. Some
small utility buildings may blow over or away. Flooding causes major damage to
lower floors of all structures near shoreline. Massive evacuation of residential
areas may be required.
Ex: Andrew 1992, Camille 1969 and Labor Day 1935
Where they form:
Hurricanes typically form between 5 to 15 degrees latitude north and south
of the equator. This is because of the Coriolis effect. The Coriolis effect is the the
effect of the rotation of the earth on the wind flow. At the equator, the winds
tend to cancel out so hurricanes cannot form. The Coriolis effect is also
responsible for why hurricanes in the Northern Hemisphere rotate
counterclockwise, and in the Southern Hemisphere rotate clockwise. Then, they
thunder across the warm oceans of the world such as the Atlantic, the Gulf of
Mexico, the Caribbean, and the Western Pacific Ocean (where they are called
typhoons), up to higher latitudes
Every tropical ocean except the South Atlantic and Southeast Pacific
contains hurricanes (Hurricanes do not occur in the South Atlantic Ocean, where
the waters are too cold for them to form). The most active ocean basin in the
world --- the Northwest Pacific --- averages 17 hurricanes per year. The western
Pacific Ocean contains a wide expanse of warm ocean water. The second most
active is the eastern North Pacific, which averages 10 hurricane
Hurricanes are generally a summer phenomenon, but the length of the
hurricane season varies in each basin, as does the peak of activity. Hurricane
season in the Atlantic is from June to November when the seas are at their
warmest and most humid, which are ripe conditions for a hurricane to develop.
http://weather.jsums.edu/hurricane.htm
Hurricanes striking new places?
The South Atlantic had been considered free of tropical cyclones—that is,
until March 2004, when a mysterious storm later dubbed Hurricane
Katarina made landfall in Brazil. In October 2005, Vince became the first
tropical storm ever recorded in Spain. And in the Arabian
Sea, Gonu became a Category 5 in June 2007—that region’s strongest
tropical cyclone on record. After weakening, Gonu brought unprecedented
damage from rain, wind, and flooding to parts of Oman and Iran.
The areas hurricanes originate from.
Names for hurricanes in certain areas.
Some Facts:
Many of today's big hurricanes including Katrina are not formed in the deep
tropics like other past legendary hurricanes, but much closer to the States.
Most hurricanes die at sea when they pass over areas of cooler water because
there is less warm moist air to fuel the hurricane.
The worst hurricane damage is often caused by a storm surge. A storm surge is
like a giant wall of water pushed onshore by hurricane winds.
Past Hurricanes:
History from National Hurricane Center
 Hurricane Keith (Category 3)-Keith began developing on 28 September
when a tropical depression formed over the northwestern Caribbean Sea. The
cyclone moved slowly northwestward on the 29th as it became a tropical
storm, then it rapidly intensified into a Category 4 hurricane on the 30th
while drifting westward toward the coast of Belize. Keith was responsible for
24 deaths - 12 in Nicaragua, 5 in Belize, 6 in Honduras, and 1 in Mexico. The
deaths in Belize occurred when two catamarans broke loose during the
storm, while 5 of the deaths in Honduras occurred when an airplane
disappeared near Roatan Island. Damage to property, agriculture, and
tourism in Belize was estimated at $225 million.
 Hurricane Katrina 2005 (Category 3)-Katrina was one of the most
devastating hurricanes in the history of the United States. It is the deadliest
hurricane to strike the United States since the Palm Beach-Lake Okeechobee
hurricane of September 1928. It produced catastrophic damage - estimated
at $75 billion in the New Orleans area and along the Mississippi coast - and is
the costliest U. S. hurricane on record. Tropical cyclone formed from the
combination of a tropical wave, an upper-level trough, and the mid-level
remnants of Tropical Depression Ten. A tropical depression formed on August
23 about 200 miles southeast of Nassau in the Bahamas. Moving
northwestward, it became Tropical Storm Katrina during the following day
about 75 miles east-southeast of Nassau. The storm moved through the
northwestern Bahamas on August 24-25, and then turned westward toward
southern Florida. Katrina brought hurricane conditions to southeastern
Louisiana, southern Mississippi, and southwestern Alabama.
 Hurricane Rita-Following less than a month after Hurricane Katrina
devastated large parts of the central Gulf Coast region, Hurricane Rita
was the second hurricane of the season to reach Category 5 status (on
the Saffir-Simpson scale) in the Gulf of Mexico. This marked the first
time on record that two hurricanes reached Category 5 strength in the
Gulf of Mexico in the same season. Additionally, it was only the third
time that two Category 5 storms formed in the Atlantic Basic in the same
year.
 Hurricane Andrew 1992 (Category 5)-One of the most destructive United
States hurricanes of record started modestly as a tropical wave that emerged
from the west coast of Africa on August 14. Andrew produced a 17 ft storm
surge near the landfall point in Florida, while storm tides of at least 8 ft
inundated portions of the Louisiana coast. Andrew also produced a killer
tornado in southeastern Louisiana
Hurricane Andrew