TEMPORAL AND SPATIAL VARIABILITY OF BLACK SEA HYDRODYNAMICS AND CHLOROPHYLL: A CONCENTRATION WITH CONNECTION TO WIND FORCING

Abstract

Spatial and temporal variability of the Black Sea surface circulation with the link to chlorophyll-a concentration and surface winds is investigated using Satellite data from Archiving, Validation, and Interpretation of Satellite Oceanographic data (AVISO), Sea-viewing Wide Field-of-view Sensor (SeaWiFS), and Quick Scatterometer (QuikSCAT) with the Self-Organizing Maps (SOMs). Six spatial patterns with temporal variability were identified for the surface currents Pattern-1 (Sevastopol Cyclonic and Batumi Dipole Eddies, 21%), Pattern-2 (Cyclonic RIM Current and Anti-cyclonic Batumi Eddy, 16%), Pattern-3 (Anti-cyclonic Sevastopol and Batumi Eddies, 17%), Pattern-4 (Cyclonic RIM Current and Cyclonic Batumi Eddy, 21%), Pattern-5 (Anti-cyclonic RIM Current and Batumi Dipole Eddies, 15%), Pattern-6 (Anti-cyclonic RIM Current and Multi Eddies, 10%). It is found the change of the bi-modal characteristics in 2000-2009 with the fall bloom being more significant than the spring bloom. The surface circulation Pattern-4 (cyclonic RIM current and Batumi eddy) is associated with the occurrence of the fall bloom. Evident connection of negative NAO and negative ENSO to the Pattern-4 circulation implies the large-scale atmospheric effect. Possible connection of these patterns to the climatological indices, such as the North Atlantic Oscillation (NAO) and the East Atlantic/West Russian (EAWR), oscillation are also discussed.