16 July 2008 R/V Wecoma cruise - Plume Feature Tracking

After we finished sampling the La Push line we spent the night steaming back to the mouth of the Columbia to start a Feature Tracking exercise in the 'young' plume. Grant Law from the modeling team provided a list of way points/times designed to sample across a range of surface salinities within the plume, including a point just outside the plume front. This is a challenge because the plume is very dynamic and changes shape and size dramatically with the tides (see attached movies). We cast the CTD at these 10 stations at the appropriate times, and collected water at three stations from four depths (surface, chlorophyll max where there was an oxygen peak, below chlorophyll max where there was an oxygen minimum, and deep). One of these three stations was outside the plume. Then we did a second feature tracking exercise that evening, but with no water samples.

Feature Tracking way points/times, daytime, 15 July 2008

Feature Tracking way points/times, nighttime, 15 July 2008