File format description for meteorology, oceanography, and wave spectra data from buoys (National Oceanographic Data Center F291 format)

Format last changed: September 1, 2006
Document last edited: April 3, 2009 by Steven Rutz, National Oceanographic Data Center

THIS FORMAT IS USED TO REPORT METEOROLOGICAL, OCEANOGRAPHIC, AND WAVE SPECTRA DATA FROM MOORED BUOYS, PRIMARILY FROM THE NATIONAL DATA BUOY CENTER, AND FIXED LAND STATIONS. THE FORMAT CONTAINS THIRTEEN DATA RECORD TYPES TO:

• IDENTIFY THE BUOY POSITION AND OTHER DESCRIPTIVE INFORMATION;
  
• REPORT THE METEOROLOGICAL MEASUREMENTS;
  
• REPORT WAVE ENERGY SPECTRA AND WAVE DIRECTION;
  
• REPORT SUBSURFACE PHYSICAL, BIOLOGICAL AND CHEMICAL OCEANOGRAPHIC MEASUREMENTS; AND
  
• REPORT DETAILED INFORMATION ON CONTINUOUSLY MEASURED WIND SPEED AND DIRECTION.
  

NOTES ON UPDATES TO FILE FORMAT

- F291 FORMAT, ALSO KNOWN AS FILE TYPE 291, REPLACED FILE TYPE 191, WHICH REPLACED FILE TYPE 091.

03/30/1981 - ADDED WIND SPEED AND DIRECTION TO RECORD TYPE '2'
12/28/1981 - ADDED RECORD TYPES '6' AND '7'
11/04/1985 - ADDED RECORD TYPE '8'
01/01/1988 - ADDED RECORD TYPE '9'
01/30/1991 - DESIGNED F291 TO:

• RELABEL RECORD TYPES - RECORD TYPES 1 THROUGH 5 BECOMING A THROUGH E; ADD NEW RECORD TYPE F; AND RELABEL 6 THROUGH 9 AS G THROUGH J;
• ADD A PRESENCE OF A RECORD INDICATOR IN RECORD TYPE 'A';
• REDEFINE RECORD TYPE B BY DELETING "HIGHEST CREST" AND "DEEPEST TROUGH" AND INSERTING "WATER LEVEL";
• IDENTIFY RECORD TYPE C AS "NON-DIRECTIONAL WAVE SPECTRA DATA RECORD";
• DELETE DEFINITION OF COLUMNS 27 THROUGH 33 IN RECORD C AND REPLACE WITH 7 BLANKS;
• ADD A DURATION OF SAMPLING FIELD AT THE END OF RECORD D;
• DEFINE RECORD TYPE E TO PROVIDE ONLY SUBSURFACE CURRENT INFORMATION; AND
• DEFINE NEW RECORD TYPE F TO PROVIDE SUBSURFACE PHOTOSYNTHETIC ACTIVE RADIATION.

05/01/1992 - REFINED DEFINITION OF OBSERVED TIME IN RECORDS A THROUGH J TO BE "END OF MET. DATA ACQUISITION, ROUNDED TO THE BEGINNING OF THE NEAREST WHOLE MINUTE." TIME TAG OF DATA ARCHIVED PRIOR TO THIS DATE REFLECTS NEAREST WHOLE HOUR OF MET. DATA ACQUISITION. ALSO, FOR RECORD C, BLANK SPACES 27-30 ARE DEFINED AS "END OF WAVE DATA ACQUISITION, ROUNDED TO THE BEGINNING OF THE NEAREST WHOLE MINUTE."

01/01/1995 - ADDED TWO NEW RECORDS TO 291 TO HANDLE WPM DATA:

• DEFINED RECORD TYPE K TO PROVIDE EXPANDED RESOLUTION FOR NONDIRECTIONAL CENTER FREQUENCY AND WAVE SPECTRA DATA; AND
  
• DEFINED RECORD TYPE L TO PROVIDE EXPANDED RESOLUTION FOR CENTER FREQUENCY OF THE CO AND QUAD SPECTRA. THE "SENSOR OUTPUT" FIELD WAS ALSO ADDED TO INDICATE THE TYPE OF SENSOR.

03/17/2000 - FOUR DIGIT YEAR

• TO ACCOMMODATE FOUR DIGIT YEARS, THE FORMER FILE DATE FIELD COL 4-9 (THAT WAS USED FOR YEARS FOR THE NODC REFERENCE NUMBER) IS NOW USED TO HOLD THE YYYYMM OF OBSERVATION AND IS CALLED OBS YEAR/MONTH.

04/21/2000 - ADDED NEW COMMENT RECORD M

• ADDED NEW M RECORD FOR COMMENTS. IT CAN OCCUR AT ANY PLACE IN THE FILE.

09/01/2006 - ADDED NEW PARAMETERS TO RECORD J, COLUMNS 83 THROUGH 101 (THESE COLUMNS WERE BLANK SPACES).

• HOURLY LOW ATMOSPHERIC PRESSURE
• TIME OF HOURLY LOW ATMOSPHERIC PRESSURE
• HOURLY PEAK WIND SPEED
• DIRECTION OF HOURLY PEAK WIND SPEED
• TIME OF HOURLY PEAK WIND SPEED

NODC CODE TABLE 0108 (WMO 4501)
CODE   WEATHER
----   --------------------
0      CLEAR (NO CLOUD AT ANY LEVEL)
1      PARTLY CLOUDY (SCATTERED OR BROKEN)
2      CONTINUOUS LAYER(S) OF CLOUD(S)
3      SANDSTORM, DUSTSTORM, OR BLOWING SNOW
4      FOG, THICK DUST OR HAZE
5      DRIZZLE
6      RAIN
7      SNOW, OR RAIN AND SNOW MIXED
8      SHOWER(S)
9      THUNDERSTORM(S)