Detection of thermal effluent discharge using sea surface nautical radar images

This letter presents the patterns of thermal effluent discharge determined by sea surface images that are acquired by nautical X-band radar. By averaging the sequential image series, we detect an obvious echo band pattern at the drain outlet of a power plant. The detection of microscale (less than 1 km) thermal effluent features using the low-grazing-angle nautical radar approach has received little attention up to now. The field sea surface temperature data confirmed that the echo band matches the spatial distribution of the thermal effluent discharge. By observing hourly image cases, we also confirm that this echo band moves approximately two times per day and that this oscillation is dominated by the tidal current.