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parameters under the local climate (low temperatures, icing, rough sea state, etc.)
taking into consideration the distance from land. The variations of the interannual
climatic regimes that are connected with changes of the water surface state and of the
insolation are also important. Climate conditions of the functioning of the ecological
monitoring system in the zone of oil extraction put de
nite restrictions on the
structure of the measurement system. These restrictions are usually connected with
the absence of possibilities for the free arrangement of the measuring and transmitting
devices in any arbitrary point of the aquatory; and for this reason the tasks of mea-
surements planning and the choice of effective algorithms for data processing are of
great concern.
An investigation of such a dynamic environment as the water systems demands the
creation of complex algorithms for the data processing of the
field observations
including a set of various models giving a possibility to reconstruct the spatial image
of the studied object basing on the incomplete information. The water systems
(oceans, seas, rivers, etc.) were investigated during last decades by means of
fl
flying
and
floating laboratories. This gave the opportunity to develop the effective methods
for the description of the dynamics of the water systems having different spatial scales.
In most cases, the
fl
field and satellite observations are connected with the measure-
ments of temperature, salinity, dissolved oxygen, current directions and velocities.
The set of hydrophysical observations is more detailed in the anthropogenic zones.
Let us designate a point on the water surface by φ latitude and by ʻ longitude.
A rectangular coordinate system (
, z), where the z axis has the value z = 0 on the
water surface and value z > 0 with depth, is selected to describe the sets of the
observation data. In these coordinates any measurement is represented as a function
ʾ
φ
,
ʻ
, z, t) which is a time-dependent random variable. The processing of the sets of
such values demands the application of special methods. As a rule, these methods
include non-stationarity reduction procedures using spatio-temporal discretization.
The choice of spatio-temporal scales is de
(
φ
,
ʻ
ned by the dynamic characteristics of the
water space and by the speci
c tasks that must be reached. Table 4.1 describes the
scheme of Fig. 4.1 and explains a possible structure of the interconnections between
spatial and temporal scales. It is observed that the accumulation of data sets by the
monitoring system may be realized taking into consideration discrete situations
distinguished in the framework of a problem that should be solved. A certain level
of reliability in the assessment of the system state under study can be achieved only
when a mathematical model is used. It combines space and time into a single
interwoven continuum.
The data sets containing the experimental estimations of the circulation char-
acteristics for the sea environment always include periodical, unperiodical, sta-
tionary and non-stationary
fluctuations. That explains why the sets of measurements
should be corrected, taking into account the scalability of the processes under study.
Hence, follows the planning of the special features of the measurements.
The study of the oil pollution of the World Ocean is one of the most important
problems of environmental monitoring. The global scale of this process demands
the application of monitoring systems, giving the possibility of controlling the water
environment over enormous areas. Satellite-based systems are an example of such
fl
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