The file is in ASCII
format and contains 287,114 records of 110 characters long (including CR/LF).
The records are built according to the proposed format, given in the IMMA document,
updated 14 March 2007 (www.cdc.noaa.gov/coads/e-doc/imma/imma.pdf).
The idea behind this format is that the user can easily start with the data, without
having to concern about unit conversions.
All data has been expressed in present day SI-units (e.g. UTC, Celsius, nautical
miles, degrees, m/s and hPa). In the laboring process of keying
the data from different sources, duplicate records may have been keyed when more
than one source was available from the same voyage. Usually these records are
not exact copies, but are more or less complementary to each other. The identification
of the duplicates is handled in the ShipLogbookID file (ShipLogbookid21.txt).
If the user wants to avoid duplicates, he/she has to ignore those ID’s that
have the Duplicate-field in the ShipLogbookID file set to other values than 0.
| Variable | Start | End | Format | Description |
| YR | 1 | 4 | A4 | Year (UTC) |
| MO | 5 | 6 | A2 | Month (UTC) |
| DY | 7 | 8 | A2 | Day (UTC) |
| HR | 9 | 12 | A4 | Hour (UTC) |
| LAT | 13 | 17 | A5 | Latitude in hundredths of a degree; North of the equator is positive, South of the equator is negative |
| LON | 18 | 23 | A6 | Longitude in hundredths of a degree; convention: 0-359.99, East of Greenwich |
| IM | 24 | 25 | A2 | IMMA version; 0 = this prototype version |
| ATTC | 26 | 26 | A1 | Attachment Count; in this version there is no attachment, so the count is 0 |
| TI | 27 | 27 | A1 | Time indicator; only 0 (= nearest whole hour) |
| LI | 28 | 28 | A1 | Latitude/longitude indicator; all 6 (= other) |
| DS | 29 | 29 | A1 | Not in use |
| VS | 30 | 30 | A1 | Not in use |
| NID | 31 | 32 | A2 | Not in use |
| II | 33 | 34 | A2 | ID indicator; all 10 (= composite information from early ship data). |
| ID | 35 | 43 | A9 |
Identification; In this release
a number is given that identifies the ship and the ships' logbook and the
possibility that the current record is a duplicate. With this number you can look up this information in the file: ShipLogbookid21.txt |
| C1 | 44 | 45 | A2 |
Country code; gives the nationality
of the ship that made the observation: ES = Spain FR = France NL = The Netherlands UK = United Kingdom SE = Sweden US = USA DE = Germany, in this case especially it is restricted to Hamburg DK = Denmark |
| DI | 46 | 46 | A1 | Not in use |
| D | 47 | 49 | A3 |
Wind direction (from which the
wind is blowing) in whole degrees from: 1-360; 361 = calm, 362 = variable. |
| WI | 50 | 50 | A1 | Wind speed indicator; all reported wind forces are more or less given in Beaufort classes (WI = 5); |
| W | 51 | 53 | A3 |
Wind speed; given in tenths of a meter per second. From the descriptive terms of wind force given in the observations, a first division into “Beaufort” classes resulted in the m/s given here. Most of the values are the midpoints of each Beaufort class, cf. WMO-1100. In those cases that more information was available, other values may have been used. Bft 0: 0-0.2 m/s |
| VI | 54 | 54 | A1 | Not in use |
| VV | 55 | 56 | A2 | Not in use |
| WW | 57 | 58 | A2 | Not in use |
| W1 | 59 | 59 | A1 | Not in use |
| SLP | 60 | 64 | A5 |
Sea level pressure in tenths of
hPa. Still under study; No temperature correction was applied and for this
moment the following factors have been used for the conversion to hPa:
2.54 cm in an inch 13.596 specific gravity of mercury 980.65 cm/s gravity at 45° latitude |
| A | 65 | 65 | A1 | Not in use |
| PPP | 66 | 68 | A3 | Not in use |
| IT | 69 | 69 | A1 |
Indicator for air temperatures,
originating from: 3 = mixed precision Celsius 7 = mixed precision Fahrenheit 9 = mixed precision Réaumur |
| AT | 70 | 73 | A4 | Air temperature in tenths of a degree Celsius |
| WBTI | 74 | 74 | A1 | Not in use |
| WBT | 75 | 78 | A4 | Not in use |
| DPTI | 79 | 79 | A1 | Not in use |
| DPT | 80 | 83 | A4 | Not in use |
| SI | 84 | 85 | A2 | Method by which SST was taken; 10 = implied bucket |
| SST | 86 | 89 | A4 | Sea surface temperature in tenths of a degree Celsius |
| N | 90 | 90 | A1 | Not in use |
| NH | 91 | 91 | A1 | Not in use |
| CL | 92 | 92 | A1 | Not in use |
| HI | 93 | 93 | A1 | Not in use |
| H | 94 | 94 | A1 | Not in use |
| CM | 95 | 95 | A1 | Not in use |
| CH | 96 | 96 | A1 | Not in use |
| WD | 97 | 98 | A2 | Not in use |
| WP | 99 | 100 | A2 | Not in use |
| WH | 101 | 102 | A2 | Not in use |
| SD | 103 | 104 | A2 | Not in use |
| SP | 105 | 106 | A2 | Not in use |
| SH | 107 | 108 | A2 | Not in use |