HURRICANES. The Atmosphere's Largest Event. Presented by: Catherine Charnawskas & Margaret Milligan July 31, 2004 SCE 6103. Storm Types. Tropical Storm Tropical cyclone with 39 to 74 mph winds Forms over a tropical ocean Center of the storm is warmer than surrounding air
The Atmosphere's Largest Event
Catherine Charnawskas &
July 31, 2004
Tropical cyclone with 39 to 74 mph winds
Forms over a tropical ocean
Center of the storm is warmer than surrounding air
Strongest winds near Earth’s surface
Has no fronts
200 to 500 miles wide
Dominant weather systems of continents
Forms outside the tropics
Center of the storm is cooler than the surrounding air
The strongest winds are in the upper atmosphere
Has fronts – warm and cold
700 to 1000 miles wide
A hurricane is a tropical cyclone with winds greater than 74 mph.
The typical hurricane width is 300 miles across.
3% of a hurricane’s energy
is transferred into wind and
Typhoons and Indian Ocean Cyclones
are related to hurricanes.
Hurricanes can easily last more than
a week. Atlantic hurricanes can
devastate Caribbean islands several
days before hitting the United
Hurricane season in the Atlantic ranges from June to November with
the peak in September.
Day Twelve: The hurricane continues to weaken after hitting land
often called extratropical at this stage.
Each year about 100 tropical storm form in the world. 66%
develop into hurricanes (Atlantic/East Pacific), typhoons (West Pacific),
or cyclones (Indian Ocean).
30% Western North
12% South Pacific
7% North and West
15% East Pacific Ocean
12% North Indian Ocean
12% Western Atlantic Ocean
12% South Indian Ocean
Names are different for each region.
Names are both male and female.
Names are alphabetical and alternate between male and female.
Experience shows that the use of short, distinctive given names in
written as well as spoken communication is quicker and less subject
to error than the older more cumbersome latitude-longitude
identification methods. These advantages are especially important in
exchanging detailed storm information between hundreds of widely
scattered stations, coastal bases, and ships at sea.
DID YOU KNOW?
Hurricane forecasters consider New Orleans America’s most dangerous for storm surge, since a storm could drive 20ft of water into the city.
Hurricane Watch – threat within 24-36 hours
Hurricane Warning – threat within 24 hours or less
The low pressure and high winds associated with hurricanes create huge mounds of water called STORM SURGES which cause 90% of all hurricane deaths.
Hurricane winds have been recorded at speeds up to 200 mph.
Beyond the direct damage by such winds, wind-driven waves on top of the storm surge compound the flooding problem by battering and eroding the coastal landscape and structures.
Two devastating factors of a hurricane:
Storm surge – a huge mound of water created by the low pressure and
strong winds of a hurricane. They are found especially in
shallow coastal waters. They can increase the water level
as much as 20 feet!
Wind damage – damage caused by high winds as well as waves driven by
Strongest hurricane since the
Great Hurricane of 1780!
Demillo, Rob. How Weather Works Ziff-Davis Press, Emeryville, California 1994, 121-129
Williams, Jack. The Weather Book 1st Edition 1992 Vintage Books, New York, New York, 131-151
American Meteorological Society Project Atmosphere “Hazardous Weather Teacher’s Guide” 1992 pg 21-24
Allaby, Michael. How the Weather Works Reader’s Digest, Pleasantville, New York. 1995. 84-87