Category Archive

  Here are the results of two AUV missions performed on 5/16 and 5/17 to observe the offshore extent of the river plume during max ebb using elevated CDOM signatures to define the boundaries of  the plume.  The 5/16 mission was performed during strong southerly wind conditions (blowing directly into the inlet) while the 5/17 mission was performed during minimal … Read More

Hello everyone, just wanted to pass along some of the work the SIO CORDC group has been performing offshore with the REMUS AUV.  On 5/8/2012 we ran a REMUS mission supporting the Guza dye release.  We’ve overlaid the Rhodamine signature observed by our AUV on the hyperspectral image taken at 17:39UTC (courtesy of Luc Lenain and Nick Statom). The REMUS … Read More

Since there has been a bit of discussion about bedforms recently I thought would post a kmz of sidescan imagery from May 5th.  This survey started at the end of flood tide and the bedforms in the dredged channel were asymmetrical in flood oriented direction, by the end of the survey, 2 hrs later at the beginning off ebb tide flow,  they had reversed asymmetry to … Read More

Below is a movie made by Cassia Pianca showing changes in low-tide morphology during the experiment. Focus on the short-scale features right along the shoreline – you will see them steadily move toward the inlet at a rate of about 50 m in 8 days (6 m/day).  Hmm.  If this doesn’t show up in the blog, I’ll email it. movieSmallLowTide … Read More

Today I tried initial analyses on “vBar” pixel instruments to measure tidal currents in the inlet. These are based on Chris Chickadel’s work and seemed potentially applicable to this situation of co-aligned waves and currents in the inlet. Below shows the locations of estimates. The figure below shows ebb current estimates for each of the three lines. Locations of zero … Read More

The ‘Maple’ group from BIO, Dalhousie and UMaine arrived Tuesday. Our objective is to characterize suspended particles (size distribution and composition) and relate it to ocean color. We have already scouted the river, taken grab samples and water samples for grain size, and have completed a drift station with a LISST and Digital Floc Camera through the mouth of the inlet. In the … Read More

Posting on behalf of Rocky Geyer:  These are near-surface velocity vectors from the WHOI REMUS at max ebb on May 4th in the north channel. Maximum ebb currents are well over 1 m/s. Lots of bathymetric steering, but some interesting free lateral shear zones as well.

Here is a composite image from 12 days of SWIFT drifter runs through the inlet spanning many different tide/wind/wave conditions.  The color scale is the surface turbulence dissipation rate, which is generally correlated with strong wave-current interactions in the two channels.  Preliminary turbulence metrics and bulk wind, wave, and current values are posted for each day at http://herschel.apl.washington.edu/darla/SWIFT/, along with an … Read More

Here is an update on the remaining schedule for drifter and dye releases. DYE RELEASES: Thursday: There will be no dye released.   Note, this is a change from the previous schedule. Friday May 11th:      Begin releasing dye at 0800:   Release dye for 1.5 hrs – (to just before slack).  Sampling on both ebb and flood. Saturday May 12th:    Begin releasing … Read More

The imagery above is a preliminary mosaic of the New River inlet plume on May 2, at about 1150 EDT (the companion data to Gordon Farquaharson’s microASAR data in his May 4 post).  Brightness in the image indicates relatively warmer temperatures, and I’ve adjusted the contrast to highlight the plume, making the warmer land white. The plume on this day … Read More