Monitoring of sea surface currents by using sea surface temperature and satellite altimetry data in the Caspian Sea

The spatial and temporal monitoring of Sea Surface Currents (SSCs) has a crucial importance in the study of the strategic environmental assessments. Although the geostrophic currents have been calculated by altimetry data, in this study, we show these currents have an appropriate correlation with the Sea Surface Temperature (SST). Two different methods are used to estimate the SSCs. First, we propose a model for calculating the geostrophic currents via removing the effects of Mean Sea Surface (MSS) from the Sea Surface Height (SSH), and second, the optical flow method (Horn-Schunck) has been applied to two sequential SST imageries to extract the SST patterns movements. In the first part of results, we map the geostrophic currents on the SST surface to explain the physical events like eddies, and in the second part, we calculate the optical flow and compare them with the geostrophic currents. Because there are no appropriate validation currents in the Caspian Sea, we use the SST products corrected by NASA and no changes have been performed on them in this study. We conclude that both optical flow and geostrophic currents show the same results but in different schemes. The schematic results shown in this article can provide new and small-scale phenomena to see that movements of sea surface have meaningful aspects.