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connection with the study of global ecodynamics . Natural disasters on the whole
and tropical cyclones in particular, are considered as interactive components of
global ecodynamics. It may be suggested that the approach we have described could
be considered as giving the possibility of forecasting the beginning of a tropical
cyclone. This approach differs drastically from traditional conceptions. However, to
produce an operational system would require routine processing, in real time, of
vast amounts of data as well as the determination of reliable thresholds to prevent
false alarms. It may then become a question of cost-bene
t. In practical terms, given
that it takes quite some time interval between the detection of a cyclone and its
landfall, would there be any practical advantage if we have an extra 12
24 h
-
warning?
Tropical cyclones are, of course, only one of several major natural disasters
which affect humankind; there are also earthquakes,
fires, volcanic eruptions
and many more. It is, of course, desirable, where possible, to give advance warning
of an impending disaster so that people can take evasive action. An earthquake
strikes suddenly and, as we know, often without speci
fl
oods,
c warning and a lot of
scienti
c research has been devoted to attempting to predict earthquakes. In a sense,
a tropical cyclone strikes suddenly; it comes in from the ocean and its damage is
(mostly) done where and when it reaches the land. But before it makes landfall it
has been tracked for quite a while and it has built up as it has travelled across the
ocean, gathering strength as it goes. The problem is not so much making an initial
prediction but on following the cyclone over a matter of a few days before it makes
landfall and predicting exactly where it will strike the land. The issue is not so much
detecting the start of the typhoon but trying to predict its path accurately in order to
make precise predictions of where and when it will strike the coastline. When it
starts, it has not reached its full strength, it is a severe weather condition that is
revealed by conventional weather forecasting and observation; navigators, at sea or
in the air, can take evasive action. If the study presented is able ultimately to
contribute to detecting a cyclone earlier than it would be detected by conventional
methods that could be very useful. But we are a long way far from being in that
situation yet. Remote sensing has its role to play
and indeed it has a large part in
the tracking of a hurricane and in providing input to models for predicting the path
of a hurricane. From the point of view of humankind, the issue is not to predict or
detect the beginning of a hurricane, but to predict its development and the path that
it will travel. Claims for supposed bene
—
ts of remote sensing that are not really
relevant to bene
tting mankind only discredit the subject.
Analysis of numerous calculations of I
m
(t) for different tropical cyclones shown
that if it is calculated at the same time for a large region
ʞ
basing on data delivered
by meteorological stations and satellites, then I
m
(
is a two-
dimensional distribution of instability indicator. In this case, sustained splash of the
I
m
(
ˆ
,
ʻ
, t)(
ˆ
,
ʻ
)
∈ ʞ
ʻ
0
)
and monitoring system is to begin probability control of this zone. Figure
7.25
gives
example of such operation.
Consideration of examples that could show the instability indicator character-
istics is possible only when cyclone track lies in a zone of meteorological stations
ˆ
0
,
ʻ
0
, t) t
∈
ˆ
0
,
[t
1
,t
2
] shows that tropical cyclone is starting in coordinates (
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