5.3 The Metadata File
Users should next create a metadata file and place it in the sub-directory created above in section 5.2. A
metadata file is a simple text file containing important information regarding the collection of the data. For example,
it will typically include the location, date, and time of data collection. This information is crucial for scientific data
interpretation. Common metadata fields are described in Appendix I. The Wave Data Processing Toolbox is
designed to read a metadata file that has specific formatting. These files are instrument-specific. We provide
example metadata files for each instrument in the Wave Data Processing Toolbox package of m-files. The files
include metaRDI.txt for the RD Instruments ADCP, metaNortek.txt for the Nortek Aquadopp AP and
metaSontek.txt for the Sontek Argonaut. It is recommended that users copy the included metadata file for their
instrument into the subdirectory created in section 5.2 and use it as a template for their metadata file.
Once the metadata file is created, users should run the proprietary software package specific to their
instrument in order to obtain ASCII file output of processed wave measurements. Step-by-step instructions for the
proprietary software are provided in sections 5.4 for the RD Instruments ADCP, in 5.5 for the Sontek Argonaut and
in 5.6 for the Nortek AP. Included in these instructions are suggested processing options (where available) for each
instrument.
5.4 Processing for an RD Instruments ADCP
The RD Instrument ADCP records three different types of time series from which wave properties may be
computed: pressure, range to the surface along each of its four beams (i.e., water level), and orbital velocities of the
surface waves taken from three bins nearest the surface in each of the four beams. It is possible to estimate non-
directional wave energy spectra, and thus wave height and period, from any of the three time series, but the velocity
time series are required for definition of the directional distribution of the wave energy.
The WavesMon software package processes the raw binary ADCP data file and produces a series of
computed data files. Pressure time series are output to files named Pressyyyynnddhhmmssxx.txt, where Press is
pressure, and the remaining characters are year (yyyy), month (nn), day(dd), hour (hh), minute (mm), second (ss),
and milli-second (xx). Time series of the range to surface are output to files named Strkyyyynnddhhmmssxx.txt,
whereas time series of orbital velocities are output to Velyyyynnddhhmmssxx.txt. The orbital velocity
measurements are used to calculate directional wave spectra, which are saved in output files called
DSpecyynnddhhmm.txt, where Dspec is directional spectra, and the remaining characters are year (yy), month (nn),
day (dd), hour (hh), and minute (mm) of the sample average. Data from all three methods are used to compute non-
directional spectra, which are saved in files called PSpecyynnddhhmm.txt, SSpecyynnddhhmm.txt, and
VSpecyynnddhhmm.txt where the PSpec* are derived from the pressure measurements, SSpec* are derived from the
range to surface measurements, and VSpec* are derived from the orbital velocity measurements. Time series of
wave parameters such as significant wave height, peak wave period, and peak wave direction are output in a file
called *_LogData.000.
Users are cautioned against re-running WavesMon in a directory in which WavesMon was previously run.
Doing so creates an additional time series of wave parameters called *_LogData.001, rather than overwriting the
previous time series. The Wave Data Processing Toolbox assumes WavesMon was run once in a directory and that
only one time series file called *_LogData.000 exists in the directory. Users are referred to RD Instrument’s Waves
User’s Guide and the RDI Waves Primer for detailed WavesMon processing instructions and information regarding
WavesMon’s various processing options.
5.4.1. Start WavesMon
Double-click the WavesMon icon on your desktop to start WavesMon. Alternatively click the start menu
and select all programs then RD Instruments and then WavesMon.
In the WavesMon File menu select New Setup. Then select Playback in the Choose a realtime or
playback dialogue and click OK. Click OK again if a Tip pops up.