FormatB for Non-Directional Spectral Wave Data

ASCII FormatB provides heave spectra and the observed or derived parameters for all types of wave instruments producing non-directional wave data.

For each wave record there will be several 80 character records as follows:

  1. Station Identification Record
  2. Administrative Information Record
  3. One or more Additional Parameters Records (Optional)
  4. One or more Wave Height - Wave Period Records
  5. Several Frequency-Bandwidth-Spectral Density Records
  1. Station Identification Record
    • FORMAT (A10,5X,A20,5X,A10)
    • Station Type 10 character field A10 e.g. AE for AES buoy - See Table I
    • Station Name 20 character field 5X,A20 e.g. West Sea Otter 
    • OSD Station Identifier 10 character field 5X,A10 e.g. C46204
  2. Administrative Information Record
    • FORMAT (2F10.4,F8.1,I4,2I2,I6,F8.1,E12.3,2X,A2,I4,2I3,I4)
    • Latitude, Real F10.4 (degrees), Negative is south latitude
    • Longitude, Real F10.4 (degrees), Negative is east longitude
    • Depth of Water, Real F8.1 (meters)
    • Year of Observation, Integer I4
    • Month of Observation, Integer I2
    • Day of Observation, Integer I2
    • Time of Observation, Integer I5 (HHMM)
    • Observation date and time are recorded in UTC.
    • Length of Recording, Real F8.1 (Minutes)
    • Sampling Frequency, Real E12.3 (Hz)
    • Quality Code (spectra, VCAR & VTPK), 2 character field 2X,A2 - See Table II
    • Number of Additional Parameters, Integer I4
    • Number of Wave Heights, Integer I3
    • Number of Wave Periods, Integer I3
    • Number of Spectral Estimates, Integer I4
  3. Additional Parameters Record(s) (Optional)
    • FORMAT (5(E12.5,A4))
    • Parameter 1, Real - See Table III for parameters
    • Parameter Code 1, 4 character field
    • Parameter n, Real
    • Parameter Code n, 4 character field
  4. Wave Heights/Periods Record(s)
    • FORMAT (8(F6.2,A4))
    • Wave Height 1, Real (m)
    • Wave Height Parameter Code 1, 4 character field  - See Table III for parameters
    • Wave Height n, Real (m)
    • Wave Height Parameter Code n,  4 character field  - See Table III for parameters
    • Wave Period 1, Real (sec)
    • Wave Period Code Parameter 1, 4 character field  - See Table III for parameters
    • Wave Period n, Real (sec)
    • Wave Period Code Parameter n, 4 character field  - See Table III for parameters
  5. Frequency/Bandwidth/Spectral Density Records
    • FORMAT (6E12.4)
    • Frequency 1, Real (Hz)
    • Bandwidth 1, Real (Hz)
    • Density 1,  Real (m²/Hz)
    • Frequency n, Real (Hz)
    • Bandwidth n, Real (Hz)
    • Density n, Real (m²/Hz)

TABLE I - WAVE INSTRUMENT TYPE CODES

TYPE CODE Description
AE AES ODAS buoy. (6m NOMAD, 3m DISCUS or Watchkeeper)
AW AES buoy data with bad Watchman payload. (Truncated spectra, VCAR=VWH$, VTPK=VTP$)
MI Miros Radar
PC Pressure cell
ST Staff gauge
SW Swartz gauge
WA Non-directional waverider buoy (Datawell)
WC Directional WAVEC buoy (Datawell)
WD Directional Waverider buoy (Datawell)
WP Non-directional WRIPS buoy
WR Non-directional Waverider

TABLE II - QUALITY CODES

The quality codes are based on the IGOSS quality codes. Quality codes are assigned subjectively to individual spectral records based on the shape of the spectral curve and relative values of significant wave height (VCAR) and peak period (VTPK) as recomputed from the spectra by OSD. No assessment of any additional reported parameters is implied by the quality code.

QC Flag Description
0 Blank - No quality control (QC) has been performed
1 Good - QC has been performed: record appears correct
3 Doubtful - QC has been performed: record appears doubtful
4 Erroneous - QC has been performed: record appears erroneous
5 Changes - The record has been changed as a result of QC 
6 Acceptable - QC has been performed: record seems inconsistent with other records
7 Off Position - There is a problem with the buoy position or mooring.  Data may still be useful.
8 Reserved
9 Reserved - indicates missing elements

TABLE III - PARAMETER CODES

Parameter codes are GF3 standard where applicable.

WAVE HEIGHT CODES
VCAR Characteristic significant wave height (m)
VWH$ Characteristic significant wave height (reported by the buoy) (m)
VCMX Maximum zero crossing wave height (reported by the buoy) (m)
SHE1 WES sea height (m)
SWHT Swell height (m)
VAV1 Average heave from the non-synoptic part of WRIPS buoy data (m)
VMNL Depth of the deepest trough (m)
VMXL Height of the highest crest (m)
VMX1 Maximum zero crossing wave height from the non-synoptic part of WRIPS buoy data (m)
VST1 Maximum wave steepness
WAVE PERIOD CODES
VTPK Wave spectrum peak period (s)
VTP$ Wave spectrum peak period (reported by the buoy) (s)
SEP1 WES sea period (s)
SWPR Swell period (s)
VTD1 Dominant period (s)
VTZA Average zero crossing wave period (s)
VZA1 Average zero crossing period from the non-synoptic part of WRIPS buoy data (s)
SPECTRAL CODES
BAND Bandwidth of spectral estimates
FREQ Frequency of spectral estimates
LCF$ Low frequency cut-off for wave spectra, calculated from the dispersion relation
VCXX Autospectrum of north-south tilt (C22)
VCXY Cospectrum of north-south and east-west tilt (C23)
VCYY Autospectrum of east-west tilt (C33)
VCZX Cospectrum of heave and north-south tilt (C12)
VCZY Cospectrum of heave and east-west tilt (C13)
VQXY Quadspectrum of north-south and east-west tilt (Q23)
VQZX Quadspectrum of heave and north-south tilt (Q12)
VQZY Quadspectrum of heave and east-west tilt (Q13)
VSDN Spectral density (equivalent to C11)
VSMB The ratio of spectral moments 0 and 1 (m0/m1)
METEOROLOGICAL & OCEANOGRAPHIC CODES
WDIR Direction from which the wind is blowing (°)
WSPD Horizontal wind speed (m/s)
WSS$ Horizontal scalar wind speed (m/s)
GSPD Gust wind speed (m/s)
ATMS Atmospheric pressure at sea level (mb)
DRYT Dry bulb temperature (°C)
SSTP Sea surface temperature (°C)
SLEV Observed sea level
SST1 Average sea temperature from the non-synoptic part of WRIPS buoy data (°C)
HAT$ Water temperature from high accuracy temperature sensor (°C)
DIRECTION and POSITION CODES
LTG$ GPS latitude (reported by the buoy) (°)
LNG$ GPS longitude (reported by the buoy) (°)
MAGN Magnetic variation from true north (°)
SED1 WES sea direction (°)
SWDR Direction from which swell is coming (° relative to true north)
VPED WAVE SPECTRUM PEAK ENERGY DIRECTION(°)
VSPR Wave directional spread from cross spectra
OTHER CODES
ADNB Number of fourier transform blocks in analysis
ADST DIWAR receiver signal strength
ADSV DIWAR receiver signal strength variance
AST1 Internal temperature from the non-synoptic part of WRIPS buoy data
AST2 Internal temperature from the synoptic part of WRIPS buoy data
NBD1 The number of bad samples in a surface elevation time series
QCF$ The indicator encoding which MEDS QC tests have failed
QCP$ The indicator encoding which MEDS QC tests have been performed
RECD The record number of the tape containing the raw data
SIDE The side number of the tape containing the raw data
TAPE The tape number of the tape containing the raw data
UPD$ The update date of the record as YYYYMMDD
WOI$ The WAVEOB indicator group 00IaImIp from code section 0 of the code.