New methods of sea surface current and water quality measurement using video images are introduced.
1) Using the wide images taken by the video installed on top of the high building, the front of the Tokyo bay mouth was observed. The movement of the front is clearly observed by the stack image taken from the video images. From the stack images of the form left by the ship, we can also estimate the velocity at the monitoring site.
2) In order to estimate the water quality, we use the wake (the form) left by the ship. The normalized R/B and G/B ratio were proportional to the concentration of the chlorophyll a measured by the water quality observation system installed on the ferry boat, “Tokyo-wan ferry Kanayamaru”.