Decadal Fluctuations in North Atlantic Water Inflow in the North Sea Between 1958-2003: Impacts on Temperature and Phytoplankton Populations

Impacts of decadal fluctuations in North Atlantic water inflow in the North Sea between 1958-2003 on temperature and phytoplankton populations were investigated. The study area was divided into 10 regions on the basis of hydrodynamic and bathymetric criteria. The 106,607 samples available from 1958 to 2003 in the study area were used. The results showed that the changes in the PCI did not reflect the changes observed in the diatom and dinoflagellate groups, highlighting the importance of using information at the taxon level in order to fully assess the changes in phytoplankton. The long-term trends and spatial variability observed in the chemicophysical and biological parameters were not consistent across the whole North Sea, which demonstrated the significance of processes occurring at smaller spatial scales.