Dataset: VPR images and log files from cruise RR2004 in the Pacific Sector of the Southern Ocean and cruise TN376 in the South Indian Ocean (Jan 2020 to Feb 2021)

Location: 

R/V Thomas G. Thompson cruise  TN376: South Indian Ocean
R/V Roger Revelle cruise RR2004: Pacific Sector of the Southern Ocean along 150W|

Methods & Sampling:

To assess the large microplankton and small mesoplankton community alongside fine-scale measurements of temperature, salinity, and fluorescence, a Video Plankton Recorder II (VPR, from SeaScan Inc.) was towed behind the ship across the shelf break. The VPR consists of a towed body, containing a Seabird Electronics Inc. CTD (SBE 49 FastCat), oxygen sensor (SBE 43), fluorometer (ECO FLNTU-4050), ECO Triplet (ECO BBFL2-123), PAR (photosynthetically active radiation; Biospherical Instruments Inc. QCP-200L), and a synchronized video camera and xenon strobe (Davis et al., 2005). The VPR was towed at 10 knots (5.1 m s-1), undulating between depths as shallow as 5m and as deep as 120m approximately every 6 minutes. This provided a minimum horizontal resolution of 1.8 km throughout the tow.

Description of package contents within the "Data Files" and "Supplemetnal Files" sections:

VPR data presented in two types: images (tif format, *.tif) and log files for the hydrographic, bio-optical and navigation data (text format, *.combo). The images come in at 30 frames per second and the log files are 1 second averages. So there is not 1-to-1 mapping.

Each VPR tow (vpr1, vpr2, vpr3, etc.) has subdirectories called d### (year day #), then h## (hour), then the roi tifs collected during that hour and the ctd.dat file of corresponding physical data. 

Example relative storage path within a tif image file zip:
RR2004/vpr/rois/vpr1/d362/h23/roi3.8594409700.tif
<cruise_id>/vpr/rois/d<year day #>/h<hour>/roiN.timestamp.tif

ROI naming convention is roiN.timestamp.tif  where timestamp is milliseconds since midnight.
Tif file name example: roi0.4565601000.tif

N is the thread number in the processing stream, taking on values 0 through 3.  This is a remnant from a prior incarnation of the software, not relevant to science use.  Please ignore.

File name format: mmddhhminss.combo where mmddhhminss is VPR tow start date/time.