1. Water exchange between partly enclosed coastal bay (Pakri Bay) and open sea (the Gulf of Finland).
Vassiljeva, S.*; Raudsepp, U.; Talpsepp, L.
Marine Systems Institute, Tallinn University of Technology, Akadeemia tee 21B, Tallinn, Estonia *
Problem description
Significant part of suspended particulate matter and nutrients in the Gulf of Finland are of coastal origin.
The Gulf of Finland has rather complicated coastline and bottom topography. The bending coastline with many small islands divides the coastal area into a number of small, partly enclosed bays.
This case study aims on identification of physical processes that contibute to the coastal and open sea water exchange at the transition zone of partly enclosed Pakri Bay and the Gulf of Finland.
Coastal upwelling
Wind from east
Strong wind
Conclusion
Coastal upwelling events are major processes that cause intensive water exchange in partly enclosed Pakri Bay.
Winds from the east force and maintain coastal upwelling that penetrates to Pakri Bay.
Upper layer currents are towards the North-West-South
Lower layer currents are towards North-East-South
Series of hydrographic and current meter measurements were analyzed, but one characteristic event was shown.
Inflow to Pakri Bay
Temperature
Salinity
Density
BV frequency
Upwelling
Pakri Bay
Gulf of Finland
UPPER LAYER
Currents to NWS
Currents to NES
LOWER LAYER