Tropical Cyclogenesis and Ecoinformatics Methods - New Ecoinformatics Tools in Environmental Science: Applications and Decision-making - page 624

receiving from radio-locators of side observation on the satellites are given by Mur
and Fen (1979).
It is clear that the search of the indicator-predictors of tropical hurricanes is
necessary to perform at the same time together with the study of all atmospheric
processes that happen above the ocean and offshore. A set of these processes
includes tornados, storms, hurricanes, and typhoons. A whirlwind (tornado) is one
of the insidious and sudden natural formations in the atmosphere. It is a rotating
funnel-shaped cloud which stretches from the bottom of the thundercloud to the
Earth 120 km h − 1 , but

' s surface. The characteristic tornado wind speeds are 65

-

sometimes this magnitude reaches 320 km h − 1 and more.
The USA territory is the most characteristic region where tornados are rather
frequent phenomena, though tornados happen all over the world. During the period
1961

2004, over the USA territory, tornados took away the lives of 83 people per
year, on the average. Most often, tornados take place in the eastern states adjacent to
the Gulf of Mexico and in February and March their frequency of occurrence is at a
maximum. On the territories of Iowa and Kansas, tornados are most frequent in May-
June. The average amount of tornados over the USA territory is estimated at

-

* 800

per year, 50 % of which falls on April June. The territorial heterogeneity of the

frequency of occurrence of tornados in the USA has stable characteristics: in Texas

-

—

—

120 tornados per year, and in the north-eastern and western states 1 tornado/year.

For instance, only in April and November 2002 there were more than 100 tornados
that caused numerous destructions with more than 600 cases of insurance payments.
The element does not spare other countries, too. For instance, the winter hurricane
“ in 2002 over Europe caused numerous destructions and insurance pay-

ments reaching more than 1 billion dollars. For instance, the hurricane Charlie in the
USA in 2004 over the states Florida, Cuba, and Jamaica, causing 19, 2, and 1 human
victim, respectively. More than 150 thousand people remained without telephonic
communication, and the damage exceeded 11 billion dollars.
Historical chronology of hurricanes happening over the American continent
shows that during one year the frequency of occurrence of hurricanes is non-uniform:
92 % of events fell on August-October with an approximately uniform distribution.
Typhoons can cause a local rise of the ocean

Janette ”

s level by several meters and, if it
takes place near the coastline, a 10-m wave is formed

'

flooding the lowlands at an
enormous rate. For example, numerous typhoons took place in 2000 over Taiwan,
Japan, South Korea, and other global regions. So, the typhoon

fl

falling on 20
August at a rate of 360 km h − 1 onto Taiwan during several hours ruined 25-
buildings (banks, schools, of

“ Billis ”

ces of companies, and dwelling houses), with the
damage of 48 million dollars. In late August, the typhoon “ Prapiroon ” stormed over

181 km h − 1 . The international airport in
Shanghai was closed for some time. In the World Ocean there are seven regions of
the origin of typhoons located near the equator. The main cause of typhoons

the East-China Sea at a wind speed of 43 -

'
appearance is the heating of several tens of meters of the ocean water above the
critical level (26.8 C). The satellite monitoring of typhoons has made it possible to

trace their routes. A trade-wind-caused typhoon moves mainly westward, gradually
turning to the north-east and east under the in

°

fl uence of Coriolis force. Up to 47 %