Tidal elevation and currents: progressive or standing?

Inlet goons:

We deployed a current meter for 24 hours near the mouth of the inlet, just offshore of the
access road (where UW is building a condo complex out of pipes).

The currents  are close to in-phase with the tides. High tide=strong  flood, low tide=strong ebb. Slack is 90-degrees out of phase relative to a sinusoid, and thus slack is about 3 hours after high or low tide. The plot shows this.

The green dots are the pressure in dbars (close to m), so about a 1.2 m tide range on April 20-21, 2012. The blue dots are the currents along the channel (major axis) (1.25 m/s ebb (at low tide) and 0.8 m/s flood (at high tide)).

For this 24 hr period, max flood was maybe 1/2 hr before high tide, max ebb was maybe 1/2 hr before low tide.

Yesterday (April 23) the ebb was almost 3 knots (1.5 m/s) up the channel a km or so (around the bend) (drifting boats with GPS). Our marker floats were pulled under and we could not see them until the flow slowed way down! These are interesting conditions in which to work. The divers are tough as nails and a little bit insane, so they are getting the job done.

[Plot by Sean Kilgallin and Seth Zippel, data provided by Britt Raubenheimer, CAR-E, Danik, Jenna, Levi, Regina, David drove boats and hauled lines and heavy frames up and down in wicked currents.]

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