Mesoscale Sea Surface Currents Derived from Multi-sensor Satellite Imagery

The aim of the study presented herein is to use multisensor / multi-channel satellite images to compute meso-scale surface currents in the Northern and Central Baltic Proper. The images were acquired by the Thematic Mapper (TM) aboard Landsat, the Synthetic Aperture Radar (SAR) aboard ERS-2, the Wide-Field Scanner (WiFS) aboard the IRS satellites, and the Seaviewing Wide Field-of-View Sensor (SeaWiFS) aboard Orbview-2 during extensive cyanobacterial blooms in July 1997 (Northern Baltic Proper) and in August 1999 (Central Baltic Proper). The two methods applied for this study are a maximum cross-correlation (MCC) analysis and a differential method based on the Optical Flow Constraint Equation (OFCE). Our example results demonstrate that the computed surface current fields complement model results provided, e.g., by local hydrographic agencies, particularly when their results are calculated for a mean water depth of some meters and on a much coarser grid.