Select a point on the ocean in the map. The resulting tracks show where four (4) surface drifters released near that point travelled over the past two weeks. Each line grows thicker and redder over time, or correspondingly, with distance along the track from the release point.
By exploring patterns over the whole map you can find important features of circulation in the Salish Sea. Drifters move landward and seaward, often 10 km or more, with the twice-a-day tides. They also tend to move persistently seaward over the 14 days, forming the upper, outgoing, branch of the estuarine exchange flow.