Hydrological fronts seen in visible and infrared MODIS imagery of the Black Sea

peer reviewedIn the paper, an examination of hydrological fronts in the Black Sea is presented based on visible and infrared Aqua Moderate Resolution Imaging Spectrometer (MODIS) imagery obtained in 2008-2013. First the images were preliminary treated (e.g., via applying a median filter) and then the fronts were detected by means of the Sobel operator. Further procession of the fields of the gradient norm thus obtained helped to get the generalized schemes of the front density for different years and seasons. On analysis of such schemes it was shown that the strongest thermal and optical fronts of the Black Sea are located in the near-coastal area. Nevertheless, analysis of the front density contrasts in the open sea was discovered to be very helpful as well, because it provided important information on the trajectories of the main macro- and mesoscale circulation patterns in the basin such as the Rim Current, Batumi eddy, and eddies of the Anatolian coast