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Meteorological Conditions Along The Polish Coast And Hydrodynamic
Conditions In The Polish Part Of The Southern Baltic Sea
Jan Malicki & Wlodzimierz Krzyminski
Institute of Meteorology and Water Management
Maritime Branch
Waszyngtona 42
81-342 Gdynia
Abstract
The weather conditions played main role in extension of the flood waters carrying
contaminants over the sea surface. On turn of July and August 1997, the Institute of
Meteorology and Water Management in Gdynia carried out both standard
meteorological observations on land and hydrological measurements including sea
currents during the cruise of RV Baltica.
At the beginning of the period from 25 th of July until 10 th of August, the atmospheric
circulation didn’t induce strong winds what caused wide spreading of river waters over
the surface of the sea. In 27 th - 29 th of July during stormy weather the deep low caused
increase of the wind velocity. The wind increased from 4-5°B to 7-8°B on 28 th of July
and its direction changed to W-SW and later to SW. The highs were dominating over
the Baltic Sea since 6 th of August. The winds 2-4°B were variable or from NE-E
direction in that time. The changes of the wind direction and velocity are presented on
the basis of the measurements from the coastal stations in Swinoujscie, Leba and Hel.
Precipitation occurred at the beginning of the described period. Intense rain (17 mm -
17 1/m 2 ) was observed in Swinoujscie area on 3rd of August only.
The currents were measured both in the gulfs and in the open sea area (fig. 1). In the
first case they were measured by means of the standard current instrument (SACM) at 5
meters depth while in the open sea area the Acoustic Doppler Current Profiler (ADCP)
system was used to record the flow at 10 meters depth under way.
During the first part of the cruise, the waters were directed into the gulf in the vicinity
of Hel peninsula, i.e. toward SE and SW, while in the central part of the Gulf of Gdansk
the currents at 5 meters depth turned out toward East. This formed a cyclone pattern of
the flow in the whole Gdansk Gulf, except its western part where anticyclone branch
existed, in the area of the Slupsk Channel the currents at 10 meters depth were southern
mainly. In the Pomeranian Bay area the currents followed the changes of the
atmospheric circulation during the period of the measurements. The currents were weak
before the stormy weather while their speed increased significantly after 6 th of August
together with change of their direction from the surface to the bottom.
