Metadata from Accession 667


Experiment name:        not available
Principal Investigator: not available
PI's affiliation:       Scottish Mar Bio Assn
Mooring Name:           not available
Mooring position:       57.263 deg N,   10.362 deg W
Instrument depth:       47 meters
Seafloor depth:         2229 meters
Times:                  starts 12 Apr 1981, ends 15 Oct 1981
Time increment:         30 minutes
Instrument type:        Aanderaa


  parameter         min     mean      max       sd     days

speed (cm/sec)      0.00    24.23    63.20    11.07    185.8
dir (deg true)      0.00   164.77   359.02    84.00    185.8
u (cm/sec)        -45.80     2.59    60.65    18.10    185.8
v (cm/sec)        -56.93    -7.40    53.09    17.91    185.8
temp (deg C)        8.95     9.92    11.08     0.41    185.8
pressure (db)     118.70   145.25   467.90    35.40    185.8


BODC has provided the following cautionary note: 

The pressure measurements are only suitable for relative depth
confirmation and for evaluation of the motion of the mooring
system. The pressure record shows that the rig suffered knock-down
on occasions throughout the deployment; the most severe displacement
of this meter was of the order of 300m and occured during 30
to 31 May 81 and on 5 Aug 81. 

Our comment: 

This record was made with an Aanderaa current meter. The nominal
speed threshhold of this meter is 1.5 cm/sec, and a common practice
is to set below-threshhold speeds either to the threshhold value
or to half the threshhold. In this case, however, below-threshhold
speeds were set to zero by the originating PI, as were concurrent
directions. In processing historical data we normally reset below-
threshhold Aanderaa speeds to half the threshhold, but have not
done so in this case because the direction information has been
lost. 

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