A typhoon (from the Chinese taifun, "great
wind") is a tropical cyclone that occurs in the western
Pacific Ocean and is usually confined to a band between
latitudes 6 degrees and 35 degrees, both north and south.
They frequently occur in the vicinity of the Philippine
Islands, the South China See, the Ryukyu Islands, and
the Taiwan Strait.
The typhoon consists of a cyclonic storm of unusually
low atmospheric pressure, formed over the water and accompanied
by winds that may reach velocities of 100 to 150 miles
per hour in the most active parts of the vortex.
Winds rotate around the center or "eye" of the
storm in a counterclockwise direction in the Northern
Hemisphere and clockwise in direction in the Southern
Hemisphere.
The typhoon's path is marked by widespread and lowering
dark clouds, torrential rains, and surging seas; it quickly
dissipates as it moves over land. Cloudiness may
cover an area measuring almost 2,000 miles in diameter.
Before the arrival of the typhoon, the atmosphere is sultry
and oppressive, and a mercury barometer exhibits a peculiar
pumping action. Typhoons may develop at any time
during the year, but occur most frequently (in the Northern
Hemisphere) between July and November, at which time the
doldrums are farthest north of the equator. The
average frequency of occurrence for the entire typhoon
region is approximately 20 to 25 storms per year.
Web Sites
Catalog
Search the library's catalog for: typhoons and cyclones.
Databases
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