0. Introduction
LMR.5 is a hybrid format, packed binary plus characters, designed for efficient re-expression of ocean surface data from the National Climatic Data Center's TD-11 (Tape Deck-11) or other formats. Packed binary methods are employed to store information common to all of TD-11, to which a variable-length string of characters is appended to represent the remainder. This is the complete report format, containing all available fields, supplemental data from original formats (e.g., elements that underwent a questionable conversion), and erroneous characters, as well as "uncertain" duplicates. It has an attachment feature that would allow easy expansion (to add derived data) or contraction (to fix the length) of a report. Nevertheless, it averages roughly one-half the size of a less complete 148-character TD-11 representation (given 8-bit character size).
It is assumed that the reader is familiar with techniques for
transferring a binary block into memory and then extracting into
INTEGER variables the bit strings whose lengths are given in Tables
F0-1 through F0-4. Refer to supp. H for more information. For a
general discussion including the advantage in execution time and
storage relative to traditional techniques see [3].
# Field Description True value Units* Base Coded Bits
------------------------------------------------------------------
0 RPTIN n/a n/a n/a n/a 16
1 BOX10 10° box 1≤648** 1*** 0 same 10
2 YEAR 1800≤2054 1 1799 1≤255 8
3 MONTH 1≤12 1 0 same 4
4 DAY 1≤31 1 0 same 5
5 HOUR 0≤23 1 -1 1≤24 5
6 X lon 0≤359.9 0.1°E -1 1≤3600 12
7 Y lat -90.0≤90.0 0.1°N -901 1≤1801 11
8 XYI lat/lon indic. 0≤3 1 -1 1≤4 3
9 CD card deck 0≤999 1 -1 1≤1000 10
10 SID source ID 0≤254 1 -1 1≤255 8
11 ST ship type 0≤7 1 -1 1≤8 4
12 QI quality indic. 0≤2 1 -1 1≤3 2
13 DS dup status 0≤5 1 -1 1≤6 3
14 DC dup check 0≤2 1 -1 1≤3 2
15 TC track check 0≤1 1 -1 1≤2 3
16 PB pressure bias 0≤2 1 -1 1≤3 2
----
section total 108
------------------------------------------------------------------
* "Units" gives the smallest increment of the data that has been
encoded. Thus a change of one unit in the integer coded value
represents a change in the true value of one of the units shown.
** m≤n denotes "from m through n inclusive."
*** Units of 1 are explained in the text describing each section.
__________________________
# Field Description True value Units Base Coded Bits
-------------------------------------------------------------------------
17 DI wind dir. indic. 0≤5 1 -1 1≤6 3
18 D wind direction 1≤362 1° 0 same 9
19 WI wind speed indic. 0≤3 1 -1 1≤4 4
20 W wind speed 0≤102.2 0.1 m s-1 -1 1≤1023 10
21 VI vis. indic. 0≤2 1 -1 1≤3 2
22 VB visibility 90≤99 1 89 1≤10 4
23 PW present weather 0≤99 1 -1 1≤100 7
24 W1 past weather 0≤9 1 -1 1≤10 4
25 W2 2nd past weather 0≤9 1 -1 1≤10 4
26 P sea level pressure 870.0≤1074.6 0.1 mb 8699 1≤2047 11
27 TI temp. indic. 0≤5 1 -1 1≤6 4
28 A air temp. -99.9≤99.9 0.1°C -1000 1≤1999 11
29 WB wet bulb temp. -99.9≤99.9 0.1°C -1000 1≤1999 11
30 DPT dew point temp. -99.9≤99.9 0.1°C -1000 1≤1999 11
31 S sea surface temp. -99.9≤99.9 0.1°C -1000 1≤1999 11
32 BI bucket indic. 0≤2 1 -1 1≤3 4
33 C total cloud amt. 0≤9 1 -1 1≤10 4
34 NH lower cloud amt. 0≤9 1 -1 1≤10 4
35 CL low cloud type 0≤10 1 -1 1≤11 4
36 HI cloud height indic. 0≤1 1 -1 1≤2 2
37 H cloud height 0≤10 1 -1 1≤11 4
38 CM middle cloud type 0≤10 1 -1 1≤11 4
39 CH high cloud type 0≤10 1 -1 1≤11 4
40 WD wave direction 0≤38 1 -1 1≤39 6
41 WP wave period 0≤30 1 s -1 1≤31 5
42 WH wave height 0≤49.5 0.5 m -1 1≤100 7
43 SD swell direction 0≤38 1 -1 1≤39 6
44 SP swell period 0≤30 1 s -1 1≤31 5
45 SH swell height 0≤49.5 0.5 m -1 1≤100 7
46 A6 allowance #6 flag 0≤1 1 -1 1≤2 2
----
section total 174
-------------------------------------------------------------------------
# Field Description True value Units Base Coded Bits
-----------------------------------------------------------------
47 CK checksum n/a n/a n/a n/a 14
48 AC attachment count 1≤15 1 0 same 4
----
section total 18
----
total 300
-----------------------------------------------------------------
# Field Description True value Units Base Coded Bits ----------------------------------------------------------------- 49 AL attachment length 1≤255 1 0 same 8 50 AID attachment ID 1≤15 1 0 same 4 51 AD attachment data n/a n/a n/a n/a n/a -----------------------------------------------------------------
Once a given field has been extracted into a coded value, the true value can be reconstructed by reversing the process:
true value = (coded + base) * unitsThe above true value example is reconstructed by (1286 + (-1000) * 0.1) = 28.6°C. NOTE: in each coded value, zero is reserved as an indicator of missing data. Of course, none of BOX10, YEAR, MONTH, X, or Y should ever be missing, although DAY and HOUR may be missing.
Explanations for each field in Tables F0-1 through F0-4 are given
under the corresponding headings that follow, where all information
refers to the true value (unless explicit mention is made to the
contrary). This supplement is largely self-contained, although some
reference is made to TD-11 documentation [5], [6],
[7] for fields
outside the regular section.* More information about some of the
fields, particularly those not in TD-11 or related to duplication
elimination, will be found in supp. I,
supp. J, or supp. K. The
various indicators show the reliability or precision of the data they refer
to, and may be extant only if the data are also non-missing (possibly
in the erroneous attachment). Algorithms are expressed in FORTRAN.
_________________________
* Notice is hereby given that some code descriptions, such as
those for present weather, are quoted or paraphrased from [5] or [12]
without any further indication or credit.
_________________________
1. Location Section
0) RPTIN
These bits are reserved for use of the RPTIN unblocking utility, where
available (e.g., NCAR). Otherwise they may be ignored.
1) BOX10 10° box
See supp. G for a description of the 10° system,
and supp. H for related software.
2) YEAR
The year can range from 1800 to 2054.
3) MONTH
1=January,2= February,...,12=December.
4) DAY
Day of the month.
5) HOUR
00 to 23 GMT.
6) X longitude
7) Y latitude
Position in tenths of a degree +N, -S, +E.
8) XYI lat/lon indicator
XYI shows the precision to which X and Y were originally keyed, or if
they are estimates derived later by interpolation between known
positions (XYI = 3 is defined but as yet unused):
0 = degrees and tenthsSee supp. K for details on how XYI was set. XYI = 2 (non-random tenths) indicates that the tenths positions appear to be from a deck that has a mixture of degrees and tenths (random) and whole degrees (a constant value such as 0 or 5).
1 = whole degrees
2 = non-random tenths
3 = interpolated
9) CD card deck
Number of the source card deck the report came from, as assigned by
NCDC. Each CD used is given with an approximate output period of
record in Table F1-1.
Approximate**
CD Description output period
--------------------------------------------------------------------------------
110 U.S. Navy Marine 1945-1951
116 U.S. Merchant Marine 1945-1963
117 U.S. Navy Hourlies 1952-1964
118 Japanese Ships No. 1 1930-1953
119 Japanese Ships No. 2 1934-1971
128 International Marine (U.S. recruited ships punched in-house) 1900-1978
143 PMEL (Pacific Marine Environmental Laboratory) Buoy 1975-1977
150 Pacific (U.S. Responsibility) HSST Netherlands Receipts 1939-1961
151 Pacific (U.S. Responsibility) HSST German Receipts 1862-1960
152 Pacific (U.S. Responsibility) HSST U.K. Receipts 1854-1961
155 Indian (Netherlands Responsibility) HSST 1861-1960
156 Atlantic (German Responsibility) HSST 1852-1961
184 Great Britain Marine (194 Extension) 1953-1961
185 USSR Marine IGY 1957-1958
186 USSR Ice Stations 1937-1970
187 Japanese Whaling Fleet 1946-1956
188 Norwegian Antarctic Whaling Factory Ships 1932-1939
189 Netherlands Marine 1901-1959
192 Deutsche Seewarte Marine 1855-1939
193 Netherlands Marine 1800-1938
194 Great Britain Marine 1856-1955
195 U.S. Navy Ships Logs 1941-1946
196 Deutsche Seewarte Marine (192 extension) 1949-1954
197 Danish Marine 1871-1956
281 U.S. Navy MAR (Monthly Aerological Record) 1926-1945
555* Monterey Telecom. 1966-1973
666* Tuna Boats 1971-1975
849* FGGE (First GARP Global Experiment) 1978-1979
850* German FGGE 1978-1979
876-882 NDBC (NOAA Data Buoy Center) 1972-1979
888* GWC (U.S. Air Force Global Weather Central) 1973-1979
889* AUTODIN (Dept. of Defense Automatic Digital Network) 1972-1979
891 NODC (National Oceanographic Data Center) Surface 1900-1977
897 Eltanin 1962-1963
898 Japanese 1954-1974
899 South African Whaling 1900-1955
900 Australian 1931-1979
901 FOSDIC Reconstructions (card images from 16mm film) 1868-1963
902 Great Britain Marine (184 extension) 1957-1961
926 IMMPC (International Maritime Meteorological Punch Card) 1956-1979
927 International Marine (U.S. recruited ships punched in-house) 1970-1979
928 Same as 927 including OSV (Ocean Station Vessels) 1970-1974
999* U.S. Air Force ETAC (Environmental Tech. Applications Center) 1967-1969
--------------------------------------------------------------------------------
* GTS deck (from the Global Telecommunication System); all others are manuscript
data. Decks 849-850 are considered GTS although they may have been mixed.
** Period of record is exact for CMR (supp. D), except that the starting years of
decks 156 and 193 are exact for LMR (both start in 1854 in CMR).
_____________________
Output
SID CD Description Format Char period
-----------------------------------------------------------------------------
1 mix Atlas TD-1100 ebcdic 1800-1969
2 150-2,192 HSST Pacific TD-1100 ebcdic 1854-1961
3 155 HSST Indian Exchange ebcdic 1861-1960
4 156 HSST Atlantic Exchange ascii 1852-1961
5 mix Old TDF-11 Supplement B TD-1100 ebcdic 1854-1975
6 primarily 128 Old TDF-11 Supplement C TD-1100 ebcdic 1855-1978
7 555 Monterey Telecom. TD-1100 ebcdic 1966-1969
8 mix OSV (Ocean Station Vessels) TD-1100 ebcdic 1945-1973
9 mix OSV Supplement TD-1100 ebcdic 1947-1973
10 mix MSQ 486 and 105 Omissions TD-1100 ebcdic 1854-1939
11 891 NODC Surface TD-1100 ebcdic 1900-1975
12 891 NODC Surface Supplement TD-1100 ebcdic 1902-1977
13 897 Eltanin TD-1129M ebcdic 1962-1963
14 898 Japanese TD-1129 ebcdic 1954-1974
15 899 South African Whaling TD-1129M ebcdic 1900-1955
16 900 Australian TD-1129 ebcdic 1931-1970
17 926 IMMPC TD-1129 ebcdic 1956-1963
18 mix '70s Decade TD-1129 ascii 1970-1979
19 926 IMMPC ('70s) TD-1129 ebcdic 1970-1979
20 mix OSV Z ('70s) TD-1100 ebcdic 1971-1974
21 900 Australian ('70s) TD-1129 ebcdic 1971-1979
22 ? Islas Orcadas ('70s) n/a n/a n/a
23 mix '70s Mislocated Data TD-1127 ebcdic 1970-1979
24 143,876-82 Buoy Data TD-1129 ebcdic 1972-1979
-----------------------------------------------------------------------------
0 = U.S. Navy or "deck" log, or unknown
1 = merchant ship or foreign military
2 = ocean station vessel -- off station or station proximity unknown
3 = ocean station vessel -- on station
4 = lightship
5 = buoy
6 = research ship
7 = expendable or mechanical bathythermograph (XBT or MBT)
12) QI quality indicator
An overall quality measure as yet undefined and maybe reserved for
subsequent analysis.
13) DS dup status
Indicates duplicate status to allow for retention of unclear
duplicates (see supp. K).
0 = unique
1 = best duplicate
2 = best duplicate with substitution
3 = worse duplicate, uncertain with hour cross
4 = worse duplicate, uncertain with no cross
5 = worse duplicate, uncertain with day cross
14) DC dup check
The presence of a GTS (Global Telecommunication System) and logbook
duplicate provides some location verification, with greater
credibility if sea level pressure P and sea surface temperature S
match under allowances (see supp. K).
0 = GTS and logbook match with P and S match
1 = GTS and logbook match without P and S match
2 = not GTS and logbook match
15) TC track check
TC is currently unused, but reserved to indicate if a report was:
0 = not track checked16) PB pressure bias
1 = track checked
0 = pressure bias adjustment unneeded
1 = pressure bias adjustment has been made
2 = pressure bias adjustment needed
2. Regular Section
17) DI wind direction indicator
DI shows the compass (and approximate precision) used for reporting
the wind direction:
0 = 36-point compass
1 = 32-point compass
2 = 16 of 36-point compass
3 = 16 of 32-point compass
4 = 8-point compass
5 = 360-point compass
18) D wind direction
The wind direction is stored in whole degrees (i.e., 360 point
compass), or with special codes:
361 = calmFor data converted from TD-11, a translation from the code value to D in whole degrees was made according to Table F2-1 (blank indicated an undefined conversion). All other data (Exchange format) were already recorded in whole degrees, so no translation was made. Consequently, for a given compass, only decks 155 and 156 (or source IDs 3 and 4) may have wind directions different than those shown in Table F2-1, since no checks for conformity were made.
362 = variable
----------------------------------
| DI
|------------------------
Code | 0 1 2 3 4
---------|------------------------
01 | 10 11 ?
02 | 20 23 25 23 ?
03 | 30 34 ?
04 | 40 45 45 ?
05 | 50 56 45 ?
06 | 60 68 68 ?
07 | 70 79 65 ?
08 | 80 90 90 ?
09 | 90 101 90
10 | 100 113 113
11 | 110 124 115
12 | 120 135 135
13 | 130 146
14 | 140 158 135 158
15 | 150 169
16 | 160 180 155 180
17 | 170 191
18 | 180 203 180 203
19 | 190 214
20 | 200 225 205 225
21 | 210 236
22 | 220 248 248
23 | 230 259 225
24 | 240 270 270
25 | 250 281 245
26 | 260 293 293
27 | 270 304 270
28 | 280 315 315
29 | 290 326 295
30 | 300 338 338
31 | 310 349
32 | 320 360 315 360
33 | 330
34 | 340 335
35 | 350
36 | 360 360
|
00(calm) | 361 361 361 361
99(var) | 362 362 362 362
----------------------------------
19) WI wind speed indicator
20) W wind speed
Wind speed is stored in tenths of a meter per second. WI shows the
units from which W was converted and the method by which it was
originally recorded:
0 = meter per second, estimated (or unknown)NOTE: no indication is given as to the precision from which W was converted, e.g., whole knots.
1 = meter per second, measured
2 = knot, estimated (or unknown)
3 = knot, measured
21) VI visibility indicator
22) VB visibility
VI shows whether VB was:
0 = estimated (or unknown method of observation)
1 = measured
2 = fog present (rarely-used code that is now obsolete, with special meaning in conjunction with VB = 93)
Codes 90 to 99 for VB correspond to horizontal visibility at the surface in kilometers:
90 = < 0.05 kilometersNOTE: when VI = 2, and VB = 93, it means that fog was present and visibility was not reported.
91 = 0.05
92 = 0.2
93 = 0.5
94 = 1
95 = 2
96 = 4
97 = 10
98 = 20
99 = 50 or more
23) PW present weather
Codes 00 to 99 (leading zeros are strictly notational, e.g., for use in comparison with past
weather). Codes 00 to 49 indicate no precipitation at the station
(e.g., ship) at time of observation.
00 = cloud development not observed.
01 = clouds generally dissolving or becoming less developed.
02 = state of the sky unchanged.
03 = clouds generally forming or developing.
04 = visibility reduced by smoke.
05 = haze.
06 = widespread dust in suspension in the air, not raised by wind at or near the station at time of observation.
07 = dust or sand raised by wind at or near the station at time of observation, but no well-developed dust whirls or sand whirls and no dust storm or sandstorm seen.
08 = well developed dust whirls or sand whirls seen at or near the station during the preceding hour or at time of observation, but no dust storm or sandstorm.
09 = dust storm or sandstorm within sight at time of observation, or at the station during the preceding hour.
10 = light fog (visibility 1,100 yards or more); synonymous with European term "mist."
11 = patches of shallow fog or ice fog at the station, not deeper than about 10 meters.
12 = more or less continuous shallow fog or ice fog at the station, not deeper than about 10 meters.
13 = lightning visible, no thunder heard.
14 = precipitation within sight, not reaching the surface of the sea.
15 = precipitation within sight, reaching the surface of the sea, but more than 5 kilometers from the station.
16 = precipitation within sight, reaching the surface of the sea, near to, but not at the station.
17 = thunderstorm, but no precipitation at time of observation.
18 = squalls at or within sight of the station during the preceding hour or at time of observation.
19 = funnel cloud or waterspout at or within sight of the station during the preceding hour or at time of observation.
Codes 20 to 29 refer to phenomena that occurred at the station during the preceding hour but not at time of observation.
20 = drizzle (not freezing) or snow grains.
21 = rain (not freezing).
22 = snow.
23 = rain and snow or ice pellets, type (a).
24 = freezing drizzle or freezing rain.
25 = shower of rain.
26 = shower of snow, or of rain and snow.
27 = shower of hail (ice pellets, type (b), snow pellets), or of rain and hail.
28 = fog or ice fog.
29 = thunderstorm (with or without precipitation).
Codes 30 to 99 refer to phenomena occurring at the ship at time of observation.
30 = slight or moderate dust storm or sandstorm has decreased during the preceding hour.Codes 50 to 99 indicate precipitation at the station at time of observation.
31 = slight or moderate dust storm or sandstorm with no appreciable change during the preceding hour.
32 = slight or moderate dust storm or sandstorm has begun or has increased during the preceding hour.
33 = severe dust storm or sandstorm has decreased during the preceding hour.
34 = severe dust storm or sandstorm with no appreciable change during the preceding hour.
35 = severe dust storm or sandstorm has begun or has increased during the preceding hour.
36 = slight or moderate drifting snow generally low (below eye level, less than 6 feet).
37 = heavy drifting snow generally low (below eye level, less than 6 feet).
38 = slight or moderate blowing snow generally high (above eye level, 6 feet or more).
39 = heavy blowing snow generally high (above eye level, 6 feet or more).
40 = fog or ice fog at a distance at time of observation, but not at the station during the preceding hour, the fog or ice fog extending to a level above that of the observer.
41 = fog or ice fog in patches.
42 = fog or ice fog (sky visible) has become thinner during the preceding hour.
43 = fog or ice fog (sky invisible) has become thinner during the preceding hour.
44 = fog or ice fog (sky visible) with no appreciable change during the preceding hour.
45 = fog or ice fog (sky invisible) with no appreciable change during the preceding hour.
46 = fog or ice fog (sky visible) has begun or has become thicker during the preceding hour.
47 = fog or ice fog (sky invisible) has begun or has become thicker during the preceding hour.
48 = fog, depositing rime, sky visible.
49 = fog, depositing rime, sky invisible.
50 = drizzle, not freezing, intermittent, slight at time of observation.
51 = drizzle, not freezing, continuous, slight at time of observation.
52 = drizzle, not freezing, intermittent, moderate at time of observation.
53 = drizzle, not freezing, continuous, moderate at time of observation.
54 = drizzle, not freezing, intermittent, heavy (dense) at time of observation.
55 = drizzle, not freezing, continuous, heavy (dense) at time of observation.
56 = drizzle, freezing, slight.
57 = drizzle, freezing, moderate or heavy (dense).
58 = drizzle and rain, slight.
59 = drizzle and rain, moderate or heavy.
60 = rain, not freezing, intermittent, slight at time of observation.
61 = rain, not freezing, continuous, slight at time of observation.
62 = rain, not freezing, intermittent, moderate at time of observation.
63 = rain, not freezing, continuous, moderate at time of observation.
64 = rain, not freezing, intermittent, heavy at time of observation.
65 = rain, not freezing, continuous, heavy at time of observation.
66 = rain, freezing, slight.
67 = rain, freezing, moderate or heavy.
68 = rain or drizzle and snow, slight.
69 = rain or drizzle and snow, moderate or heavy.
70 = intermittent fall of snowflakes, slight at time of observation.
71 = continuous fall of snowflakes, slight at time of observation.
72 = intermittent fall of snowflakes, moderate at time of observation.
73 = continuous fall of snowflakes, moderate at time of observation.
74 = intermittent fall of snowflakes, heavy at time of observation.
75 = continuous fall of snowflakes, heavy at time of observation.
76 = ice prisms (with or without fog).
77 = snow grains (with or without fog).
78 = isolated star-like snow crystals (with or without fog).
79 = ice pellets, type (a) (sleet, U.S. definition).
80 = rain shower, slight.
81 = rain shower, moderate or heavy.
82 = rain shower, violent.
83 = shower of rain and snow mixed, slight.
84 = shower of rain and snow mixed, moderate or heavy.
85 = snow shower, slight.
86 = snow shower, moderate or heavy.
87 = slight showers of snow pellets or ice pellets, type (b), with or without rain or rain and snow mixed.
88 = moderate or heavy showers of snow pellets or ice pellets, type (b), with or without rain or rain and snow mixed.
89 = slight showers of hail, with or without rain or rain and snow mixed, not associated with thunder.
90 = moderate or heavy showers of hail, with or without rain or rain and snow, mixed, not associated with thunder.
91 = slight rain at time of observation, thunderstorm during preceding hour but not at time of observation.
92 = moderate or heavy rain at time of observation, thunderstorm during preceding hour but not at time of observation.
93 = slight snow, or rain and snow mixed, or hail, at time of observation with thunderstorm during the preceding hour but not at time of observation.
94 = moderate or heavy snow, or rain and snow mixed, or hail, at time of observation with thunderstorm during the preceding hour but not at time of observation.
95 = thunderstorm, slight or moderate, without hail, but with rain and/or snow at time of observation.
96 = thunderstorm, slight or moderate, with hail at time of observation.
97 = thunderstorm, heavy, without hail but with rain and/or snow at time of observation.
98 = thunderstorm combined with dust storm or sandstorm at time of observation.
99 = thunderstorm, heavy, with hail at time of observation.
24) W1 past weather
25) W2 second past weather
Codes 0 to 9 have the same meaning for W1 and W2, which more or less
corresponds to that implied by the leading (tens) digit of present
weather. The period covered by W1 and W2 is 6 hours for observations
at 0000, 0600, 1200, and 1800 GMT, and 3 hours for observations at
0300, 0900, 1500, and 2100 GMT. W1 and W2 are intended to contain the
higher and lower, respectively, of two codes that describe as fully as
possible the weather during the appropriate period, or both W1 and W2
may contain the same code. W2 became effective only starting on 1
January 1982, so it should always be missing before that date.
0 = cloud covering one-half or less of the sky throughout the appropriate period.
1 = cloud covering more than one-half of the sky during part of the appropriate period and covering one-half or less during part of the period.
2 = cloud covering more than one-half of the sky throughout the appropriate period.
3 = sandstorm, dust storm, or blowing snow.
4 = fog, ice fog, or thick haze (U.S. includes thick smoke).
5 = drizzle.
6 = rain.
7 = snow, or rain and snow mixed.
8 = shower.
9 = thunderstorm with or without precipitation.
26) P sea level pressure
In tenths of a millibar.
27) TI temperature indicator
28) A air temperature
29) WB wet bulb temperature
30) DPT dew point temperature
31) S sea surface temperature
Temperatures are stored in tenths of a degree Celsius. TI shows the
precision and units that A, WB, DPT, and S were recorded in or
translated to (see supp. I):
0 = degrees Celsius and tenths
1 = whole degrees Celsius
2 = half degrees Celsius
3 = degrees Fahrenheit and tenths
4 = whole degrees Fahrenheit
5 = half degrees Fahrenheit
32) BI bucket indicator
Shows the method by which S was taken:
0 = unknownNOTE: BI values 0 and 1 are unreliable at least for U.S. recruited ships (i.e., country code 0K or 02) until starting on 1 May 1973, or perhaps earlier (see COADS Release 1, and for country codes see [6]).
1 = bucket
2 = implied bucket (an HSST SID or any match thereof)
33) C total cloud amount
34) NH lower cloud amount
For C, codes 0 to 9 show the fraction of the celestial dome covered by
all clouds. For NH they show the fraction of the celestial dome
covered by all the low (CL) clouds and, if no CL cloud is present, the
fraction covered by all the middle (CM) clouds present:
0 = clear.
1 = 1 okta or less, but not zero.
2-6 = 2-6 oktas.
7 = 7 oktas or more, but not 8 oktas.
8 = 8 oktas.
9 = sky obscured or cloud amount cannot be estimated.
35) CL low cloud type
Codes 0 to 10 show characteristics observed of clouds of the types
stratocumulus, stratus, cumulus, cumulonimbus, and their variations:
0 = no stratocumulus, stratus, cumulus, or cumulonimbus.
1 = cumulus with little vertical extent and seemingly flattened, or ragged cumulus other than of bad weather, or both.
2 = cumulus of moderate or strong vertical extent, generally with protuberances in the form of domes or towers, either accompanied or not by other cumulus or by stratocumulus, all having their base at the same level.
3 = cumulonimbus the summits of which, at least partially, lack sharp outlines but are neither clearly fibrous (cirriform) nor in the form of an anvil; cumulus, stratocumulus, or stratus may also be present.
4 = stratocumulus formed by the spreading out of cumulus; cumulus may also be present.
5 = stratocumulus not resulting from the spreading out of cumulus.
6 = stratus in a more or less continuous sheet or layer, or in ragged shreads, or both, but no stratus fractus of bad weather.
7 = stratus fractus of bad weather (generally existing during precipitation and a short time before and after) or cumulus fractus of bad weather, or both (pannus), usually below altostratus or nimbostratus.
8 = cumulus and stratocumulus other than that formed from the spreading out of cumulus; the base of the cumulus is at a different level from that of the stratocumulus.
9 = cumulonimbus, the upper part of which is clearly fibrous (cirriform), often in the form of an anvil; either accompanied or not by cumulonimbus without anvil or fibrous upper part, by cumulus, stratocumulus, stratus, or pannus.
10 = low clouds not visible, owing to darkness, fog, blowing dust or sand, or other similar phenomena.
36) HI cloud height indicator
Shows if the cloud height H was:
0 = estimated
1 = measured
37) H cloud height
Codes 0 to 10. Codes 0 to 9 show the height above sea surface of the
base of the lowest cloud or fragment thereof as given by Table F2-2.
----------------------------------
| Approximate height
|---------------------------
Code | Feet Meters
------|---------------------------
0 | 0-149 0-49
1 | 150-299 50-99
2 | 300-599 100-199
3 | 600-999 200-299
4 | 1000-1999 300-599
5 | 2000-3499 600-999
6 | 3500-4999 1000-1499
7 | 5000-6499 1500-1999
8 | 6500-7999 2000-2499
9 | ≥8000 or ≥2500 or
| no clouds no clouds
----------------------------------
38) CM middle cloud type
Codes 0 to 10 show characteristics observed of clouds of the types
altocumulus, altostratus, and nimbostratus:
0 = no altocumulus, altostratus, or nimbostratus.
1 = altostratus, the greater part of which is semi-transparent; through this part the sun or moon may be weakly visible, as through ground glass.
2 = altostratus, the greater part of which is sufficiently dense to hide the sun or moon, or nimbostratus.
3 = altocumulus, the greater part of which is semi-transparent; the various elements of the cloud change only slowly and are all at a single level.
4 = patches (often in the form of almonds or fishes) of altocumulus, the greater part of which is semi-transparent; the clouds occur at one or more levels and the elements are continually changing in appearance.
5 = semi-transparent altocumulus in bands, or altocumulus in one or more fairly continuous layers (semi-transparent or opaque), progressively invading the sky; these altocumulus clouds generally thicken as a whole.
6 = altocumulus resulting from the spreading out of cumulus (or cumulonimbus).
7 = altocumulus in two or more layers, usually opaque in places, and not progressively invading the sky; or opaque layer of altocumulus, not progressively invading the sky; or altocumulus together with altostratus or nimbostratus.
8 = altocumulus with sproutings in the form of small towers or battlements; or altocumulus having the appearance of cumuliform tufts.
9 = altocumulus of a chaotic sky, generally at several levels. 10 = middle clouds not visible, owing to darkness, fog, blowing dust or sand, or other similar phenomena, or more often because of the presence of a continuous layer of lower clouds.
39) CH high cloud type
Codes 0 to 10 show characteristics observed of clouds of the types
cirrus, cirrocumulus and cirrostratus:
0 = no cirrus, cirrocumulus or cirrostratus.
1 = cirrus in the form of filaments, strands, or hooks, not progressively invading the sky.
2 = dense cirrus, in patches or entangled sheaves, which usually do not increase and sometimes seem to be the remains of the upper part of a cumulonimbus, or cirrus with sproutings in the form of small turrets or battlements, or cirrus having the appearance of cumuliform tufts.
3 = dense cirrus, often in the form of an anvil, being the remains of the upper parts of cumulonimbus.
4 = cirrus in the form of hooks or of filaments, or both, progressively invading the sky; they generally become denser as a whole.
5 = cirrus (often in bands converging towards one point or two opposite points of the horizon) and cirrostratus, or cirrostratus alone; in either case, they are progressively invading the sky, and generally growing denser as a whole, but the continuous veil does not reach 45 degrees above the horizon.
6 = cirrus (often in bands converging towards one point or two opposite points of the horizon) and cirrostratus, or cirrostratus alone; in either case, they are progressively invading the sky, and generally growing denser as a whole; the continuous veil extends more than 45 degrees above the horizon, without the sky being totally covered.
7 = veil of cirrostratus covering the celestial dome.
8 = cirrostratus not progressively invading the sky and not completely covering the celestial dome.
9 = cirrocumulus alone, or cirrocumulus accompanied by cirrus or cirrostratus, or both, but cirrocumulus is predominant.
10 = high clouds not visible, owing to darkness, fog, blowing dust or sand, or other similar phenomena, or more often because of the presence of a continuous layer of lower clouds.
40) WD wave direction
Codes 0 to 38. Codes 0 to 36 show the direction from which (wind)
waves come, in tens of degrees:
0 = calmCodes 37 and 38 show:
1 = 005-014°
2 = 015-024°
3 = 025-034°
4 = 035-044°
5 = 045-054°
6 = 055-064°
7 = 065-074°
8 = 075-084°
9 = 085-094°
10 = 095-104°
11 = 105-114°
12 = 115-124°
13 = 125-134°
14 = 135-144°
15 = 145-154°
16 = 155-164°
17 = 165-174°
18 = 175-184°
19 = 185-194°
20 = 195-204°
21 = 205-214°
22 = 215-224°
23 = 225-234°
24 = 235-244°
25 = 245-254°
26 = 255-264°
27 = 265-274°
28 = 275-284°
29 = 285-294°
30 = 295-304°
31 = 305-314°
32 = 315-324°
33 = 325-334°
34 = 335-344°
35 = 345-354°
36 = 355-004°
37 = waves confused, direction indeterminate (wave height ≤ 4.75 meters).NOTE: In their conversion of data into TD-11, NCDC usually substituted wind direction into missing WD since 1 January 1968, when WD was no longer ordinarily reported. Instead of continuing this practice, modifications were made to properly QC the wave fields without actually substituting wind direction (see supp. J), thereby preserving any remaining information regarding whether WD was separately reported.
38 = waves confused, direction indeterminate (wave height > 4.75 meters).
41) WP wave period
The old codes for periods WP and SP (swell period) have been converted
to whole seconds as given by Tables F2-3 or F2-4, choosing the higher
of 2-second class intervals where applicable. (Periods in whole
seconds were taken in preference to the old codes if both were
available, e.g., from TD-1127 or TD-1129.)
Seconds Code Interval ------------------------------------------------- 5 2 5 seconds or less 7 3 6-7 seconds 9 4 8-9 seconds 11 5 10-11 seconds 13 6 12-13 seconds 15 7 14-15 seconds 17 8 16-17 seconds 19 9 18-19 seconds 21 0 20-21 seconds 22 1 over 21 seconds 0 - calm or period not determined -------------------------------------------------
Seconds Code Interval ------------------------------------------------- 10 0 10 seconds 11 1 11 seconds 12 2 12 seconds 13 3 13 seconds 14 4 14 seconds or more 5 5 5 seconds or less 6 6 6 seconds 7 7 7 seconds 8 8 8 seconds 9 9 9 seconds 0 - calm or period not determined -------------------------------------------------
0 = less than 0.25 meters
1 to 99 = 0.5 to 49.5 meters
Note: The above description of wave height, from the original published edition of COADS Release 1, refers to printed values rather than the stored data. Wave (and swell) height were actually stored as meters to tenths (with a half-meter increment), according to Table F0-2. This contrasts with "height in 1/2 meter increments" as used in TD-11 (i.e., 1=0.5 m, 2=1 m, etc.). However, the format of the wave and swell height fields (WH/SH) as printed by the data access programs is also "height in 1/2 meter increments." This is because all decimal points are removed by a uniform procedure: the programs divide each FTRUE value by the corresponding units as listed, for WH/SH, in Table F0-2. Only in the case of WH/SH, which have units of 0.5 m, does this produce a non-intuitive result. E.g.: LON=33.80/0.01 = 3380, versus WH=6.5/0.5 = 13 printed.
43) SD swell direction
44) SP swell period
45) SH swell height
As given by the corresponding wave fields WD, WP, and WH.
46) A6 allowance #6 flag
Both reports matched under dupelim allowance #6 (see supp.
K) were assigned a value showing the number of hours by which the HSST
Indian report lagged the deck 193 report, after which either or both reports
may have been output:
0 = six hours, or
1 = seven hours
3. Control Section
47) CK checksum
A checksum was computed and stored with each report as a measure of
reliability during storage and transmission. The checksum is computed by
INTEGER CK,J,FIELD(46),CKS
CK = 0
DO 500 J = 1,46
500 CK = CK + FIELD(J)
CK = MOD(CK,255)
IF(CK .NE. CKS) THEN
PRINT *,'ERROR. CK = ',CK,' .NE. CKS = ',CKS
STOP
ENDIF
Note that using modulus 28-1 takes into account every bit of CK, versus chopping at the eighth bit using modulus 28. In addition the top 6 bits are unused.
48) AC attachment count
Shows that AC attachments, as described in sec. 4, follow.
4. Irregular Section
The combined length of the preceding three sections is 300 bits, which is equivalent in length to 75 4-bit characters. Appended after bit 300 are AC attachments (unless AC is zero) whose purpose is to contain information that does not conveniently fit into the binary section of the format. Currently implemented are attachments 1, 4, and 5:
Attachment 1 = quality control flags generated in the quality control program.Each attachment contains three fields:
Attachment 4 = supplemental data from the original input format.
Attachment 5 = fields that contain invalid characters or out of range values in the original input format.
49) AL attachment length
AL is the length of the attachment data following AID in 4-bit bytes.
50) AID attachment ID
Numeric identifier of this attachment.
1 = quality control flags51) AD attachment data
4 = supplemental data
5 = error fields
Attachment 1. Quality Control Flags
Flag values generated by the NCDC defined QC procedure (see
supp. J) were stored in TD-11 as alphabetic characters
given in Table F4-1, together with their coded (or true value)
equivalents as stored in LMR.
Char Coded Weight Meaning Reason ----------------------------------------------------------- R 1 0 correct -- A 2 1 correctable legality B 3 1 correctable internal consistency J 4 2 suspect internal consistency K 5 2 suspect time L 6 2 suspect extreme (mean ± 4.8 σ) M 7 3 erroneous legality N 8 3 erroneous internal consistency Q 9 3 erroneous extreme (mean ± 5.8 σ) S 10 3 missing -- -----------------------------------------------------------
------------------------------------------------------------
| Possible flag values (X)
# Flag Coded Bits | R A B J K L M N Q S
--------------------------------- |-------------------------
1 ship position 1≤10 4 | X X
2 wind 1≤10 4 | X X X X X X
3 visibility 1≤10 4 | X X X
4 present weather 1≤10 4 | X X X X X X
5 past weather 1≤10 4 | X X X X
6 pressure 1≤10 4 | X X X X X
7 air temp. 1≤10 4 | X X X X X X X
8 wet bulb temp. 1≤10 4 | X X X X X X X
9 dew point temp. 1≤10 4 | X X X X X X X
10 sea surface temp. 1≤10 4 | X X X X X
11 cloud 1≤10 4 | X X X X X
12 wave 1≤10 4 | X X X X X X X X
13 swell 1≤10 4 | X X X X X X X
14 pressure tendency 1≤10 4 | X X X X
|
15 quality code 1≤43 8 |
---- |
total 64 |
------------------------------------------------------------
quality code true value = coded - 1For the flags, the coded and true values are the same.
Attachment 2.
Not currently implemented.
Attachment 3.
Not currently implemented.
Attachment 4. Supplemental Data
All fields not converted to binary and other designated fields are packed into a character string. For TD-1100, TD-1127, and TD-1129 formats this consists of all characters beginning in position 78, 78, and 79, respectively. For the Exchange format this consists of characters from positions 33-35 and 42-46. Refer to supp. I for more details on these formats.
Since the vast bulk of the data is numeric, or numeric overpunch, a 4/8/12-bit "ship" character set was used that maximizes compression but has close ties to ebcdic. These rules were followed in translation to the ship character set:
a) All numeric characters are translated into values 0-9 (equivalent to the low order 4 bits of ebcdic).
b) Spaces translate to the value 10.
c) A subset of other characters is stored as 8-bit where the first 4 bits contain 12, 13, or 14. (See Table F4-3.)
d) Characters not appearing in Table F4-3 are represented by a 4-bit flag of 15, followed by the original 8-bit character.
e) More than 2 consecutive spaces are represented by a 4-bit flag of
11, followed by a 4-bit count of the (number minus three) of
consecutive spaces that these 8 bits replaced. Thus a count of
0=3 spaces, 1=4 spaces,..., 15=18 spaces. Trailing spaces are
simply omitted.
-----------------------------------------------------
| High-order 4-bit byte
| Empty 11 12 13 14
|------------------------------------
0 | 0 3 sp (12-0) (11-0)
1 | 1 4 sp A J /
2 | 2 5 sp B K S
3 | 3 6 sp C L T
4 | 4 7 sp D M U
5 | 5 8 sp E N V
6 | 6 9 sp F O W
low-order 7 | 7 10 sp G P X
4-bit byte 8 | 8 11 sp H Q Y
9 | 9 12 sp I R Z
10 | 1 sp 13 sp & - *
11 | 8-bit 14 sp +
12 | 8-bit 15 sp
13 | 8-bit 16 sp
14 | 8-bit 17 sp
15 | 12-bit 18 sp
-----------------------------------------------------
* Read the value of the first 4-bit byte as low-order.
If "8-bit" is shown, this byte is read instead as
high-order and the next 4-bit byte as low-order. If
"12-bit" is shown, the next 8-bit byte is the original
input character. A run of n spaces is denoted by n sp.
Blank positions in the table will be defined as needed.
________________
Note: This section, Attachment 5, was accidentally left out of the published edition of COADS Release 1.
All characters within this attachment are maintained in the original 8-bit character set. When a field is encountered that has invalid characters or is out of range, the entire field is stored in this attachment. Each field is preceded by an 8-bit field identifier that contains the field number according to Tables F0-1 or F0-2 and a 4-bit field that contains the character count for the field.