ReadMe file for CO2-Hydrate Composite cruise data CD


This data CD contains the data collected at-sea during the CO2-Hydrate Composite cruise from 17 April 2006 through 20 April 2006 onboard the R/V Western Flyer, MBARI.

Data is divided in seven directories:

	CoolPix
	Digipics
	FrameGrabs
	pHdata
	ROVdata
	SONAR
	YrDyData

There is also a directory (pHprog) containing the software (in zipped file format) for reading the pH data files and an example data file.  Use WinZip to unzip this file into a temporary directory, then double-click setup.exe to begin the installation process.  You may install this program anywhere you wish.  to use this program to view the pH data files, just start the program and then click on File to select the data file to view.


CoolPix

This directory contains the Cool-Pix photos snapped during the dives.  The time-stamp on these files tells you EXACTLY when the photo was "snapped."  There are two formats: jpeg and tiff.


Digipics

These are the photos that Peter Walz and Edward Peltzer collected using a hand-held digital camera on-deck.  The photos are primarily of the hardware and how it was mounted on the ROV.  Two group photos are also included.


FrameGrabs

This directory contains five sub-directories; one for each of the ROV dives and which are numbered accordingly.  In each sub-directory is a file (e.g.  +tibr966-jpg-01.html) that when double-clicked will open in your web browser with an inter-active graphical index showing thumbnail images of each frame-grab collected during the dive.  When you click on each thumbnail, a full-size image will appear with the data overlaid.  An additional click will open the png file without the data overlay.  Use your back button to return to the graphical index.


pHdata

The pH data are stored in plain ascii text files.  Each file has an extensive header if you wish to read it directly; alternatively, there is a file reader program in the pHprog subdirectory.  Notes on the appropriate calibration constants and the offset corrections to apply at each depth can be found in my field notes.  It is very important to adjust the baseline pH to the background pH value before attempting to interpret the pHdata.


ROVdata

This directory contains five data files (one from each ROV dive in comma delimited text format) plus an Excel data file.  The first line in each text file contains the header information for that file.  Data are 15 second averages based upon the data logged at 2 sec intervals during the dive.  The Excel file contains a summary spreadsheet of all of the dive CTD data info.  The data formats are similar to the year day data files.  For more info see:  DataFormats.xls


SONAR

Data from the ROV Sonar unit (Kongsberg SIMRAD MS1000 with 675 kHz head).  Filename is the date and time that recording began.  These files require Kongsberg SIMRAD MS1000 software to read and visualize the data.


YrDyData

This directory contains all of the raw and derived CTD data.  In addition, a plot of the data as a function of depth for each day is provided in both post-script and bitmap formats.

For the raw data files, the data is logged at two second intervals and each record is time-stamped using universal coordinated time (UTC).  One file is saved for each year day.  Since our ROV dives often spanned more than one year day according to UTC, one may need to splice portions of two files together to get the complete raw data set for a dive.  The derived data files contain derived parameters (e.g., salinity instead of conductivity, depth instead of pressure) and this data is presented as 15 second averages of the raw data.

	File naming convention:

	Raw data files:	             yyyydddtibrCtdRaw.txt
	Derived data:                yyyydddtibrCtdDer.txt

For more info see:  DataFormats.xls