I’m trying to use the wavss_a_dcl_fourier_recovered data from the Oregon Offshore surface buoy. Is there any documentation or the code used to produce this data product?
I’m having trouble figuring out what the directional dimensions (named wavss_four_dim1 with length 4) represents.
Thanks!
@JohnRagland Did you ever receive a reply here?
John,
The surface moorings are equipped with the AXYS Technologies TriAxys Wave Sensor. The data processing algorithm used is proprietary, you’d need to request that information from AXYS Technologies. The sensor is configured to record 3D accelerations at 10 Hz for 20 minutes every hour and then reports the wave statistics (bulk, directional and non-directional) as NMEA sentences. An example of the raw data as recorded by the mooring can be found on the OOI Raw Data Server. OOI records and reports the data as reported by the sensor. For the Fourier Coefficients, the data format is:
NMEA Fourier Coefficients (NF)
?MNF<cr>
Format:
$TSPFB, Date, Time, Serial, BuoyID, Latitude, Longitude, Number
of Bands(N), Initial Frequency, Frequency Spacing, Number of
Directional Bands, Directional Initial Frequency, Directional
Frequency Spacing, A1 1, B1 1, A2 1, B2 1, A1 N-2, B1 N-2, A2 N-2, B2
N-2*cs<cr><lf>
The Fourier coefficients are stored in a 2D array (parameter name is fourier_coefficient_2d_array) where the dimensions are wavss_four_dim0 by wavss_four_dim1. The dimensions map to the number of bands (wavss_four_dim0 = 121, where N always equals 123) and the Fourier coefficients (A1, B1, A2 and B2, wavss_four_dim1 = 4). Other than organizing the reported data into arrays for storage in the OOI data store, no other processing is applied for this particular data set.
Hopefully this helps? If not, keep the questions coming.
Cheers,
Chris