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Sound velocity profile (SVP) measurements were collected on average every two hours throughout the survey. A total of 438 SVPs were collected for this survey. 114 SVPs were collected during cruise S-7-09-MB and 324 SVPs were collected during S-10-09-MB. In general, SVPs were collected every 2 hours, or when the survey vessel moved to a different survey block. Typically two SVPs were collected every four lines. Water column sound velocity profiles varied significantly throughout the survey, however this frequency of SVP collection was sufficient to correct for variations in sound velocity. Only one line from cruise S-7-09-MB (BlockA_230_044) shows an artifact from an uncorrected sound velocity error (smile), for part of it's length. Insufficient sound velocity data were available to correct this line, and no attempt was made to synthesize data.
SVPs were collected with an Applied Micro Systems, SvPlus 3472. This instrument provides time-of-flight sound velocity measurements using invar rods with a sound velocity accuracy of +/- 0.06 m/s, pressure measured by a semiconductor bridge strain gauge to an accuracy of 0.15% (Full Scale) and temperature measured by thermistor to an accuracy of 0.05 C (Applied Microsystems Ltd., 2005). In addition, an Applied Micro Systems Micro SV accurate to +/- 0.03 m/s was deployed on the transducer frame for real-time sound velocity adjustments at the transducer-water interface.
Data in these data tables are recorded in the following fields:
#DateTime - date and timestamp for the SVP data Pressure(dBars) - This field is actually water depth in meters SoundVelocity(m/s) - Sound velocity in m/s Temperature(C) - temperature in degrees C Battery(Vdc) - battery voltageSVPs taken at this density comprise a largely unexplored dataset that provides insight into spatial and temporal temperature variation within the Monterey Bay National Marine Sanctuary between mid-August and late December, 2009.
Information about October - December field activity data collection at <http://walrus.wr.usgs.gov/infobank/s/s1009mb/html/s-10-09-mb.fmeta.faq.html>.
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Acknowledge the U.S. Geological Survey (USGS), the Originator, when using the data set as a source. Any use of trade, firm, or product names is for descriptive purposes only and does not imply endorsement by the U.S. Government.
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Data should not be used beyond the limits of the source scale. This information is not intended for navigational purposes.
The data set is NOT a survey document and should not be utilized as such. Some USGS information accessed through this means may be preliminary in nature and presented without the approval of the Director of the USGS. This information is provided with the understanding that it is not guaranteed to be correct or complete and conclusions drawn from such information are the responsibility of the user.
Sound velocity profile (SVP) measurements were collected on average every two hours throughout the survey. A total of 440 SVPs were collected for this survey. 114 SVPs were collected during cruise S-7-09-MB and 326 SVPs were collected during S-10-09-MB. In general, SVPs were collected every 2 hours, or when the survey vessel moved to a different survey block. Typically two SVPs were collected every four lines. Water column sound velocity profiles varied significantly throughout the survey, however this frequency of SVP collection was sufficient to correct for variations in sound velocity. Only one line from cruise S-7-09-MB (BlockA_230_044) shows an artifact from an uncorrected sound velocity error (smile), for part of it's length. Insufficient sound velocity data were available to correct this line, and no attempt was made to synthesize data.
SVPs were collected with an Applied Micro Systems, SvPlus 3472. This instrument provides time-of-flight sound velocity measurements using invar rods with a sound velocity accuracy of +/- 0.06 m/s, pressure measured by a semiconductor bridge strain gauge to an accuracy to 0.15% (Full Scale) and temperature measured by thermistor to an accuracy of 0.05 C (Applied Microsystems Ltd., 2005). In addition, an Applied Micro Systems Micro SV accurate to +/- 0.03 m/s was deployed on the transducer frame for real-time sound velocity adjustments at the transducer-water interface.
Cruise index files are in comma-separated-value (csv) format, as follows:
Cast,Date,Time,Easting,Northing,Longitude,Latitude,File,Image 1,10/16/2009,"""15:38""",589233,4088072,-121.9979859,36.93447136,289_153835_SVP001.svp,S-10-09-MB_SVP001.pngData files from each are in text (.svp) format, named by the ordinal date (day of year)_UTCTIME_SVPcast# with internal structure as follows:
[header information example - information varies slightly] #DUMP 3472LOG.RAW #SvPlus S/N 3472 #New cast started on 08-14-09 at 17:19:02 #Sample rate is 15 /second #Depth increment 0.00 #Sound velocity increment 0.00 # #582714.944207046E #4083519.92296003N #DateTime,Pressure(dBars),SoundVelocity(m/s),Temperature(C),Battery(Vdc) [data record example] 08-14-09 17:19:02,0.0,1496.72,15.992,13.15 . . .
Any use of trade, firm, or product names is for descriptive purposes only and does not imply endorsement by the U.S. Government.
Although this Federal Geographic Data Committee-compliant metadata file is intended to document the data set in nonproprietary form, as well as in ArcInfo format, this metadata file may include some ArcInfo-specific terminology.
Please recognize the U.S. Geological Survey (USGS) as the source of this information.
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Some USGS information accessed through this means may be preliminary in nature and presented without the approval of the Director of the USGS. This information is provided with the understanding that it is not guaranteed to be correct or complete and conclusions drawn from such information are the responsibility of the user.