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regularly falling onto the eastern and near-equatorial regions of the continents. The
tropical cyclones are hurricanes and typhoons, taking place in the northern and
southern Paci
c, in the Bay of Bengal, the Arab Sea, in the southern sector of the
Indian Ocean, near the coast of Madagascar, and the north-western coast of Aus-
tralia. The Atlantic hurricanes form mainly in the zone con
ned to the coordinates
(10
o
N
20
o
N, 20
o
W
6
o
W) and (7.5
o
N
17.5
o
N, 30
o
W
100
o
W). The tropical
-
-
-
-
cyclones are usually called by names.
The origin of tropical hurricanes are one of displays of the tropical climate
system functioning. Numerous International and National hurricane centers study
this functioning. One of them is the US National Hurricane Center that publishes
reports with a detailed description of each hurricane case describing all phenomena
(speed and direction of the wind, precipitation, etc.) that are going with it. Basic
direction of the studies in these centers is associated with detecting and tracking the
hurricanes that are arisen. Forecasting of the trace for hurricane moving, certainly,
is important to reduce the losses. There exist many models of different complexity
and detail by means of which the efforts are undertaken to predict the hurricane
trajectory, its intensity and precipitation intensity (Gray et al. 1991; Pielke 1999).
Similar investigations are realized in the Canadian Hurricane Center (CHC) or
Atlantic Storm Prediction Centre (ASPC). During the hurricane season forecasters
carefully monitor all storms of tropical origin. When a storm begins to threaten
Canadian waters or land, specially trained meteorologists in the CHC track the
tropical storms and provide guidance to other Canadian storm prediction centers.
They work closely with the US hurricane Centre in Miami as well as municipal,
provincial and federal emergency measures organizations in order to inform the
public of expected conditions.
Forecasters at the ASPC work with many tools and technology to provide fore-
casts and warnings, including: Doppler weather radars, weather satellites, observa-
tions from a network of upper atmosphere and surface monitors, a network of
offshore weather buoys, ship reports, volunteer reports and a variety of computer
model output. The ASPC operates 24 h a day, 365 days a year, which means fore-
casters work day and night shifts as well as holidays. Supercomputer Hurricane
Prediction is used to solve the arising problems. Of course, basic tendency of these
predictions are directed to the assessment of the prospective number of hurricanes
and their intensity but not the direct detection of given hurricane beginning. A
solution to this problem results from the study by Golitsin and Vasiliev (2001), being
possible under the detailed investigation of the conditions when atmospheric con-
vective processes are developed. Under this, regular data
flows characterizing the
aquatories with dangerous wind conditions are an obligatory condition for the suc-
cess. It is possible when buoy station and methods of aquatory monitoring by means
of oceanographic satellites are jointly used. These data sources give the possibility to
have narrow observation of the zones where tropical hurricanes can begin.
Origination of the data about wind
fl
fields on the large aquatories is possible with
the radio-locators of side observations giving spatial resolution about 1 km and by
means of radio-locators with synthetic aperture with spatial resolution of 25 m.
Methodical questions of maximal wind speed evaluation basing on the information
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