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ThemostimportanttaskoftheSARservicesisto
look for the people who have fallen overboard or
drifting in the water after overturning the boats. In
the literature [3‐7,9,10,13,17,20,21,25,27], the search‐
and‐rescue areas, in waters used for the navigation,
are determined by employing the Monte Carlo
methods,Bayesianmethods,regressionmodelsforan
object’sdriftvelocity,theFokker‐Planckequationsor
certain graph models. To determine such areas, it is
necessary to obtain data about surface currents and
wind. That data are often generated by numerical
models.Theaccesstosuchdatamightbeobtainedby,
e.g., theGeographic Information System such as the
Maritime Network‐Centric Geographic Information
System Gulf of Gdansk [16]. Sometimes, some
relationsbetweenthewindandwind‐drivencurrents
are established [20]. Based on the wind parameters,
theleewayparametersalongwiththeiruncertainties
aredetermined,e.g.,bythelinearregressionor
onthe
basis of constructed probability distributions. The
potentialtotaldriftofasurvivoristhevectorsumof
the current and leeway. The position vector of a
survivoratagiventimetiscalculatedastheintegral
of the survivor’s velocity vector from the initial
momenttothe
timetincreasedbythevelocityvector
fromtheinitialmoment.
AccordingtoIAMSAR(InternationalAeronautical
and Maritime Search and Rescue Manual) [8], an
estimation of the surface current and wind
parameters can be derived from direct observations,
diagrams,charts, wind roses, reliablehydrodynamic
models and weather forecast models. The direct
observations may be obtained from the in situ
measurements,fromvesselspassingthroughanarea;
aircrafts flying over an area, installed appropriately
buoys,platformsorsatellitemeasurements.However,
suchdataarenotalwaysavailable.Bydiagramsand
charts,thelong‐termaverageseasonalparametersof
the currents and wind could
be determined.
However,thesesourcesareemployedintheareasfar
away from shores. Nevertheless, an estimation of
these parameters provided by these sources should
not be used in coastal areas, and especially in the
offshore areas less than 25 nautical miles distance
from the shore and less than 300 feet
(100 meters)
water depth. Reliable hydrodynamic models with
high resolution and weather forecasts models are
other sources of such. The authors consider these
sourcesofdata.
The first aim of this paper is to verificate the
available data on the surface currents and wind
parameters on the Szczecin Lagoon area
for the
summer season in 2017. The forecasted surface
currentsparameters have beenexamined with using
an expert method. In turn, the real and forecasted
wind parameters have been compared. Some
statisticalcharacteristics of the uncertainties of those
parameters havebeen presented. Furthermore, some
probabilisticmodelsfortheobtaineduncertaintiesof
the considered parameters have been determined.
Additionally, linear relations between the surface
currentsandwindspeedswereestablished.
The remainder of this paper is organized as
follows.InSection2,researchareaanditshydrology
conditions are described. In Section 3, the materials
and methods are presented. Section 4 contains
a
comparative analysis of numerical data on surface
currents and wind parameters collected for the
SzczecinLagoonduring thesummer season in2017.
InSection5,adiscussionoferrorsinforcingfieldsis
conducted.Section6concludes.
2 RESEARCHAREAANDITSHYDROLOGY
CONDITIONS
2.1 Researcharea
The Szczecin Lagoon
(Polish: Zalew Szczeciński)
coverswaters atthemouth ofthe Odra River. From
thenorthernsideofthislagoon,theislandsofWolin
and Uznam separate it from the Baltic Sea. In the
middle part of this lagoon, it is subdivided into the
LargeLagoon(Polish:WielkiZalew),with
thesurface
areaof
2
488 km lyingwithinPoland,andtheSmall
Lagoon(German:KleinesHaff),coveringtheareaof
2
424 km ,whichbelongsalmostentirelytoGermany.
The Szczecin Lagoon lies on the longitude: approx.
'
13 53 E
'
14 36 E
and the latitude: approx.
'
53 42 N
'
53 52 N
.Itisabout 28 km long and
over
52 km wide [1]. The southern limit of the
Szczecin Lagoon is designated by the Jasienica
channel outlet (on the west bank)and the mouth of
theKrępaRiver(intheeast).
ThePomeranianBay(Polish:ZatokaPomorska)is
connected with the Szczecin Lagoon via the straits:
Dziwna,Świna and Peennestrom.Ś
wina is the most
important for the Szczecin Lagoon hydrological
system. These straits are not the Odra River arms,
becausetheircurrentisnotarivercurrent,butitisthe
result of the constant sea and the Szczecin Lagoon
waterlevelling.
TheaveragedepthoftheSzczecinLagoonisabout
3,8 m . The largest natural depth of the Szczecin
Lagoon is
8,5 m . However, it is not a region
deprivedofshoalsandshallows.Nearly
25% ofthe
areais
02
‐meterdeep,andthehighaverageisdue
tothefactthatthereisthe
10,5 ‐meterdeepchannel
across the Szczecin Lagoon from Szczecin to Baltic
waters [1]. This channel is called the Szczecin‐
Świnoujście fairway. The Szczecin‐Świnoujście
fairway is the dredged channel in the Szczecin
Lagoonarea.
2.2 Descriptionofthehydrologicalconditionsonthe
SzczecinLagoon
TheSzczecinLagoonis
perceivedasasmallandfairly
safeareaforsailingandmotorboatsport.Thedanger
is the shape of its coastline and bottom, which in a
combination with varying hydrodynamic conditions
led already too many woes. Particularly dangerous
are squalls, which are strong and unexpected. In
addition to the wind
dynamic action, generated
waves affect also boats. The wave height is directly
relatedtothedepthofalagoonarea.
Windwavesaretheimmediatethreats.Thewave
dimensionsaredeterminedbythewind.Theduration
of the wind forcing practically does not affect the
developmentofthewave.Thefull
wavedevelopment
can take place within a period of no more than one
hour. After the wind stopping, the wave quickly