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Surface Temp Movie: Combined remote-sensing IR and in situ measurements

 

Below is a movie of surface Temperature at the New River Inlet on May 7th 2012 during the ONR-funded RIVET I experiment.   The temperature is derived by combining airborne IR (Luc Lenain in Ken Melville’s group at SIO) with in situ temperature sensors.   The top panel shows the tide level and the arrow to the right shows the currents within the inlet (at the red dot) from the WHOI (Raubenheimer/Elgar) ADCP 05.  All times are in EDT.

 

The movie can be better viewed if you click to view it full frame.  In it one can clearly see the warm jets coming out the two inlet channels.  Much of the newchannel warm plume gets turned on the bathymetry coutours and heads in the -y direction.  In addition, the alongshore (-y) propagation hugging the coast of the warm water plume is clearly evident. This plume is about 1 deg C warmer than the water 500 m offshore.    The winds and the waves on this day were relatively strong and came from the -y quadrant, driving strong flows to the south.

The mp4 version of this movie can be downloaded here

 

 

Nortek Vector ADV & Aquadop ADCP (Feddersen/Guza) data posted (updated 2X)

NOTE: May 3rd 2013: The .mat files have been updated again. The format is the same as below. Some compass and sensor orientation issues have been fixed. I highly recommend you use these new versions. Download details can be found at: http://blog.iod.ucsd.edu/RIVET/2012/09/04/ftp-data-site-is-now-up/

NOTE: .mat files have been updated as of Wed Dec 19th 10:45am PST.   Thanks to Peter Rogowski for finding issues with the time stamps.

——

The data from our 6 Nortek Aquadop ADCPs have also been posted to the ftp site in the directory called “adcp”.  See the link above for the ftp site info.   The instruments
are denoted A1 to A6.   The data files are called AQ_A1.mat and each holds a struct
that has various arrays of data (at 1 minute sampling) with format:

AQ_A1 =

mon: [30240×1 double]
day: [30240×1 double]
hour: [30240×1 double]
minute: [30240×1 double]
P: [30240×1 double]
TEMP: [30240×1 double]
Ur: [30240×25 double]
Vr: [30240×25 double]
SN: 2141
X: -7.095480269861441e+02
Y: -2.442293840566305e+02
lat: 34.532029999999999
lon: -77.344700000000003
t: [1×30240 double]
Z: [1×25 double]
HEADING: [30240×1 double]
PITCH: [30240×1 double]
ROLL: [30240×1 double]
time_adcp: [30240×1 double]
Amin: [30240×25 double]

——

The data from the 8 Nortek Vector ADVs has been posted to the ftp site.   Please see previous posts on how to access the ftp site.    The data is in a directory called “vector”.  The instruments are denoted V1 through V8.   Note, V5 was corrupted and is not posted.   The instrument deployment map can be found in other posts – but a map is included below.    The data is provided in MATLAB format.   My apologies for posting in a proprietary format but I think everyone can work with it.     The individual files are called
VECTOR_V1.mat   to VECTOR_V8.mat.    If you do a “load VECTOR_V!.mat” in MATLAB you’ll get a single variable struct that looks like (all samples at 1 Hz)

VEC_V1 =

U: [1833960×1 double]     % +x velocity in RIVET coord sytem m/s
V: [1833960×1 double]      % +y velocity in RIVET coord system  m/s
W: [1833960×1 double]     % +z velocity m/s
P: [1833960×1 double]      %pressure dbar-not corrected for atmospheric P changes
TEMP: [1833960×1 double]  % in deg C
AMP: [1833960×1 double]
CORR: [1833960×1 double]
mon: [1833960×1 double]    % monday (always 5)
day: [1833960×1 double]
hour: [1833960×1 double]
minute: [1833960×1 double]
second: [1833960×1 double]
SN: 470                               % serial # of instrument
vnum: 1                                  % number of the location (1-8)
time: [1×1833960 double]       % time in seconds from start of record
X: -42                                  % RIVET x coord (m)
Y: -1511                               % RIVET y coord (m)
LAT: 34.5207                          % LAT & LON
LON: -77.3522

 

Please let me know if you have any questions.   There may of course be bugs in the data set.  I will post updates here if I happen to find any.   Have fun.

Map of New Rivet Inlet NC bathymetry (from the ASACE FRF) in the RIVET coordinate system with the SIO (Feddersen/Guza) and WHOI (Raubenheimer/Elgar) ADV, ADCP, and wirewalker (WW) instrument locations as noted in the legend. The TopSail side of the inlet is below and the Camp Lejuene side is on top. SIO ADV locations are marked V1-V8. All locations also had a co-located pressure sensor Map of New Rivet Inlet NC bathymetry (from the ASACE FRF) in the RIVET coordinate system and many locations also had a co-located Rhodamine WT dye fluorometer. Dye was released either near x ≈ −600 m and y ≈ −300 m, or about 1.2 km further up the inlet towards the Inter-Coastal Waterway.
Map of New Rivet Inlet NC bathymetry (from the ASACE FRF) in the RIVET coordinate system with the SIO (Feddersen/Guza) and WHOI (Raubenheimer/Elgar) ADV, ADCP, and wirewalker (WW) instrument locations as noted in the legend. The TopSail side of the inlet is below and the Camp Lejuene side is on top. SIO ADV locations are marked V1-V8. All locations also had a co-located pressure sensor Map of New Rivet Inlet NC bathymetry (from the ASACE FRF) in the RIVET coordinate system and many locations also had a co-located Rhodamine WT dye fluorometer. Dye was released either near x ≈ −600 m and y ≈ −300 m, or about 1.2 km further up the inlet towards the Inter-Coastal Waterway.

New River Inlet Jetski data now posted on ftp site

The jetski data from the RIVET I experiment at the New River Inlet is now posted at our ftp site.  If you do not have ftp access, please contact falk for access.  Below are two examples of the Dye and Temperature data from two days superimposed on the New River Inlet bathymetry.

Surface dye (left, ppb) and temperature (right, ◦C) observations from (top) May 6th and (bottom) May 8th at the New River Inlet NC measured by a SIO dye and temperature mapping jetski. On May 6th, dye was continuously released near (x,y)=(−400, −250) m and on May 9th, dye was point released at (x,y)=(−1000,400) m. Note how the jetskis were able to map out the dye plume structure outside of the inlet mouth and the downstream dilution as well as the temperature between the warmed inlet and the ocean.

The listing of the ftp directory looks like:

The *.pdf files are overview figures of the data similar to the figures above.

The data files look like  data_ski_mmdd_[old,new].mat, where [new,old] are the names of our two skis.    mmdd is short for month and day.    Each data file contains the following variables

>> load data_ski_0506_old.mat
>> whos
Name           Size                Bytes  Class     Attributes

D          73885×1                591080  double
T          73885×1                591080  double
Xb          1001×1001            8016008  double
Xrl            7×1                    56  double
Yb          1001×1001            8016008  double
Yrl            7×1                    56  double
Zb          1001×1001            8016008  double
batt       73885×1                591080  double
date           1×8                    16  char
dates          7×8                   112  char
dd             1×1                     8  double
flow1      73885×1                591080  double
flow2      73885×1                591080  double
ino            1×1                     8  double
no             1×3                     6  char
t          73885×1                591080  double
t_r0           7×1                    56  double
t_rf           7×1                    56  double
tau        73885×1                591080  double
u          73885×1                591080  double
v          73885×1                591080  double
x          73885×1                591080  double
y          73885×1                591080  double

The most relevant variables are “D” (ppb),  “T” (deg C), “x” – RIVET coordinate x, “y” RIVET coordinate y,  “t” is time in seconds of the day (EDT).     Please let us know if you have any questions.

FTP data site is now up

RIVET-ers:   our ftp data site is now up.   We are slowly in the process of putting processed and quality controlled data onto it.   To access the ftp site please ftp to

ftp://rivet@ftp.iod.ucsd.edu/

or use the ftp shell program and ftp to   ftp.iod.ucsd.edu  with username “rivet”

If you would like access to the data please email falk feddersen (ffeddersen at ucsd.edu) and you’ll be sent a password.

DATA POLICY & CAVEATS:   Our data policy is similar to the Raubenheimer/Elgar (WHOI) policy and is repeated here:
1) We are actively analyzing the dye and drifter data sets from New River.    If you want to use the drifter or dye data please let us know so that the same analysis is not performed twice.

2) If you use the data, we would like to be offered the opportunity to consider co-authorships. We try not to be parasites, and if we do not feel we made a contribution, we will decline.

3) If you use the data, please let us know so we can ensure our sponsors are acknowledged.

4) Please do not distribute these data to any third parties. That means if you let your students use the data, please inform them they are not to share with anyone else. Others can contact us and we will give them the data.  This practice will ensure that everyone can be kept up to date with improved quality control, and our sponsors can be acknowledged.

5) The data have undergone a significant quality control.  However, likely some wierdness remains.  If you find anything strange, please let us know and we will update the data files.

6) If you would like to collaborate, let us know. We’d be happy to share science ideas, suggestions, and processing efforts.

FTP site format

The format of the ftp site should be fairly self explanatory.   We are only starting to put data up so the site will chane and expand.   Currently, the top level directory looks like:

Index of ftp://rivet@ftp.iod.ucsd.edu/

Up to higher level directory

Name Size Last Modified
drifter 8/29/12 8:35:00 PM
fluorometers 9/4/12 6:27:00 PM
wirewalker 9/4/12 8:54:00 PM

The fluorometer directory contains all the data from the deployed fluorometers in two sub directories  fixed_fluorometers (mounted on pipes near current meters) and towed_fluorometers (towed behind a boat).

Index of ftp://rivet@ftp.iod.ucsd.edu/fluorometers/

Up to higher level directory

Name Size Last Modified
File:SIO_fluorometer_data_report.pdf 746 KB 9/4/12 6:27:00 PM
fixed_fluorometers 8/29/12 8:34:00 PM
towed_fluorometers 9/3/12 11:27:00 PM

Let me know if you have any questions

Airborne dye movie from May 7 2012

We’ve been busy processing up the RIVET I data from the New River Inlet, which we will be posting to our ftp site soon. We’ve also been working up the airborne observations (in collaboration with Luc Lenain & the Melville lab). The video below shows a visualization of the May 7th dye release.

Animation of repeated airborne passes of the dye plume imaged with the hyperspectral imager with New River Inlet bathymetry contours.   Data is from May 7th 2012.    The dye signal is constructued by differencing light in two different wavenumber bands.

The full movie file which has much more detail can be downloaded here

 

The waves at New River Inlet are supposed to be below 50 cm later this week. I looked at the waves at the buoy every morning since February. They were bigger the 4 weeks the RIVET sensors were in the water than at any time since February! There were two pre-June tropical storms. When a few of us came to New River to poke around in October 2010, we drove thru Tropical Storm Nicole (21″ of rain in 24 hours). What are the odds…

Big waves made in-water work difficult, but also provide an opportunity to see the effect of waves on inlet processes, increasing the coolness of everyone’s data sets.

No one is left besides Britt and me (waiting for trucks to take our gear to Duck) (and of course, Greg Schmidt). Quiet. I think the Tiki Bar is considering closing until late June owing to lack-of-business. There are lots of empty tables at Rick’s, and the cul-de-sac at the north end of New River Inlet road is deserted. Not even a LARC in sight.

See you soon I hope. Steve

SWIFT runs complete

Yesterday we completed the final set of SWIFT runs, measuring surface turbulence, waves, winds, and currents through the inlet. Below is the composite of all tracks from 26 Apr to 21 May, color scaled by turbulent dissipation rate. Across all conditions, there is consistent enhanced dissipation at the channel outlets (old and new), as well as over the shoals. Other, more localized features, such as enhanced turbulence crossing fronts (and dye plumes!) are evident in the daily runs. Preliminary data products and summaries are at
http://herschel.apl.washington.edu/darla/SWIFT/

Surface turbulent dissipation rate from SWIFT drifters.

 

Thermal IR visualized flow

The attached video shows a 17 minute series of 10 second averaged images from the thermal IR cameras on the APLUW/OSU tower.  Brighter shades indicate relatively warmer temperatures.  The high tide was approximately 2 hours prior to the movie.  Note the strong northward flow which bends into the inlet and intersects a cooler front in the main channel.

5/16/2012 and 5/17/2012 River Plume Extent Monitoring Missions

5/16/2012 River plume extent as measured by CDOM during strong south wind conditions.

 

5/17/2012 River plume extent as measured by CDOM during minimal wind conditions.

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 wind conditions.  Both missions extend to 1km offshore.  You’ll notice how defined the river jet is during the 5/17 mission and how the plume extends beyond our survey lines.  In contrast, it appears the strong wind conditions during the 5/16 mission suppressed the offshore extent of the plume and pushed it in a southwesterly direction.  It’s also interesting to see the impact the wind conditions have on the mixing of the plume.  The high wind event on 5/16 diluted the plume significantly (colorbar range: 6 to 10 ppb) when compared to the low  wind event on 5/17 where the river plume saw consistent CDOM levels of ~13 ppb as it is advected offshore.