Dissipation around Pt Sal

Here’s a quick work up of the SWIFT drifts around Pt Sal from the previous few days.  The drifts are all southwards (releases are at the northernmost points for each track), and the color scale is the log10 of the TKE dissipation rate averaged over the upper 5 m.  Looks like there is a region of high dissipation were the flow separates around the headland and changes direction.

Dissipation rates from SWIFTs drifting past Pt Sal

Evidence of cross-shore exchange at Oceano 20 m isobath

Here’s a quick plot from one of Sounder’s laps around the inshore box today (14 Sep 2017).  The first leg goes along the 20 m isobath from the NW corner to the southwest corner.  The upper 10 m of water is headed onshore (red) at ~20 cm/s, and the lower 10 m of water is headed offshore at ~ 20 cm/s.  Classic cross-shore exchange?  You be the judge.  More puzzling is the lack of exchange (or much flow at all, green being ~0 cm/s) along the 10 m isobath….

Sounder transects near Pt Sal

Here’s an example of the persistent southerly flow and separation that we have seen the last few mornings with the Sounder and Sally Anne (SIO whaler) running ADCP transects around Pt Sal.  Sally Ride is on this transect now, so we should soon see what this looks like during other phases of the tide.


ADCP transect mid-day on 12 Sep 2017 going from west to east.

Shore side met stations

Two shore side met stations are up and running.  These are collocated with the OSU radar sites at Guadalupe and Pt Purisma.  Parameters measured are wind speed, wind direction, air temp, air pressure, relative humidity, and shortwave radiation.  We are working on adding long wave radiation at Gaudalupe.  The data are recorded locally, and will be available  at the end of the experiment (i.e., no telemetry).

Guadalupe met station

Pt Purisma met station

APL-UW day 1 on the water: moored SWIFTs and a sea spider deployed

APL-UW got out on the water today after a trucking company delivered both the R/V Sounder (APL-UW) and the R/V Kalipi (OSU) to Port San Luis.

R/V Kalipi and R/V Sounder on the big rig.

Once underway, APL deployed a sea spider in 20 m off Oceano and then moored SWIFTs on either side of Pt Sal.  The Pt Sal positions are along the SIO lines.  The one south of Pt Sal felt close enough to reach out and touch the rocks.

The SWIFT data are available hourly from the following links: SWIFT 24 (south of Pt Sal) , SWIFT 25 (north of Pt Sal)

Or, just view on the SWIFT map and click on the icon for most recent wave height.

Turbulence data also available via telemetry– contact Jim T to learn how to work with the binary files.

SWIFT 25 moored near Pt Sal




scripps oceanography uc san diego