The three groups, 2znznznzn, 3TnTnTnTn, and
4SnSnSnSn, are repeated for each level of measured
data. The znznznzn reports each depth in whole meters.
For example, 20001 reports a depth of 1 meter below
surface, and 20150 reports a depth of 150 meters.
Temperatures are reported by TnTnTnTn to the nearest
hundredth degree Celsius, with 5,000 added to the
temperature to indicate values below zero degree
Celsius. In our example, 20010 31820 reports a
temperature of 18.20°C at 10 meters. A report 35120
would indicate a temperature of-1.20°C. The salinity
group 4snsnsnsn is only included if salinity
measurements have been made. This group reports
salinity to the nearest hundredth of a part-per-thousand.
A report of 43472, for example, is 34.72%.
In the second portion of section 3, under-sea current
set and drift is reported. This report, if included, will be
preceded by an indicator group 66k69k3. Indicator k6
refers to WMO Code Table 2267, the method used to
correct the current measurement for the buoys
movement. Indicator k3 is the indicator for the duration
and time of the data sampling for the current
measurement from WMO Code Table 2264. Neither
are significant for decoding purposes. For each level
where the current is reported, the depth is reported by
using a 2znznznzn group, and then the direction and
speed of the current are reported in the group
dndncncncn. The dndn reports the set of the current
(direction towards) in tens ofdegrees True, while cncncn
reports the drift of the current in centimeters per second
(hundredth of a meter-per-second). For rough
approximations, doubling the meters-per-second value
yields a value in knots.
For example, 20150 18135
reports the current at 150 meters moving toward the
south (set = 180° True) at 2.7 knots (drift = 135
centimeters or 1.35 meters-per-second).
Section 4 of the report, beginning with the indicator
444, reports quality control information. Actual
movement of the buoy may be reported in this section
and may be interpreted as a surface current speed and
direction. Many values after the 444 indicator may be
ignored for normal data applications.
personnel assigned data monitor duties at activities
where the reports are received, must encode these
values to signify if the buoy is functioning properly.
Normally, if a buoy sensor is operating within
acceptable limits, the information in this section will not
appear in the transmitted report. Thus, the absence of
this section, with the exception of the 8ViViViVi and the
9idZdZdZd groups, indicates satisfactory operation Of
In order of appearance in the code, QP is the quality
of the pressure report; Q2 is the quality of the buoys
house-keeping; QTW is the quality of the sea-surface
temperature report, and 44 is the quality of the air-
temperature report; QN is the quality of the satellite
transmission; and QL and QA are the quality of the
When the quality of the reported
buoy position in section 0 is doubtful, a second
latitude/longitude group may be repeated in this
The actual movement of the buoy may also be
reported in this section as an aid in determining buoy
location. The movement of the buoy may be used as an
approximate surface water current, especially if a
drogue anchor is affixed to the buoy, The buoy
movement group, 7VBVBdBdB, begins with the
date/time of the last known position using a YYMMJ
GGgg/ group. The speed of movement, VBVB, is given
in centimeters per second (multiplied by .10). The
direction of movement, dBdB, is given in tens of
degrees. In our example, 71227 would indicate that the
buoy has moved at 2.4 knots (120 centimeters or 1.20
meters-per-second) toward the west (270° True).
The 8ViViViVi group contains an engineering
code. Ignore this group.
The 9idZdZdZd group contains buoy cable (drogue)
data. The code figure id indicates the type of drogue
used. The last 3 digits in the group, ZdZdZd, is the
length of the drogue in meters.
Surface meteorological observations from drifting
buoys are normally automatically processed and plotted
on computer-produced surface charts. The bathymetric
reports are not routinely plotted. The positions of the
buoys should be monitored and the bathymetric data
entered into TESS or MOSS when buoys are near your
operating area. These reports will expand your USW
area prediction capabilities.
What information is contained in section 2 of the
drifting buoy code?
What is the data identifier for a drifting buoy