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COMMISSION FOR BASIC SYSTEMS
MEETING OF EXPERT TEAM ON DATA
REPRESENTATION AND CODES
KUALA LUMPUR, MALAYSIA, 21-26 JUNE 2004 / ET/DR&C/Doc. 5.1(1)
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(16.VI.2004)
ENGLISH only
MANUAL ON CODES
Production of a Manual on Reporting Practices
(Submitted by the Secretariat)
Summary and Purpose of Document
As stated already in 2001, 2002 and 2003, and recommended by CBS Ext. (02), the migration to BUFR/CREX necessitates the writing of new Reporting Practices, extracted from the Manual on Codes, Volume I.1, which contains more reporting practices than formatting rules. The document shows in Appendix attempts to express the new practices.
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ACTION PROPOSED
The team is asked to comment on the document, add any appropriate comments, in particular confirm a recommendation for further consultant work to produce a set of reporting practices with appropriate common sequences linked to BUFR/CREX, based on a the regulations found in the Manual on Codes, Volume I.1. The team is asked to recommend this work for inclusion as Attachment of Volume I.2 ( or in a new volume 1.3?).
Reference:
- Manual on Codes, WMO pub. No 306, Volumes I.1 and I.2
DISCUSSION
1. It is a fact that the Manual on Codes, Volume I.1, contains more regulations related to reporting practices than formatting rules. The Volume I.2, on the contrary defines formatting systems, and practically no reporting regulations. The Volume I.1 links reporting practices to the alphanumeric coding format. The migration to BUFR/CREX will push producers and users (human decoders) of BUFR/CREX codes to consider Volume I.2, rather than Volume I.1. It is necessary to re-write the regulations on reporting practices, disconnecting them from the traditional alphanumeric format, and making them “universal”, to fit, for instance, various national Automatic Weather Station templates which would be used to report the so-called “surface synoptic observations” in BUFR. It would make the migration to TDCF easier for the programmers of automatic platform software, for the meteorologists and the observers.
2. The CBS Ext.(02) noted that reporting requirements as well as observing practices were currently included along with the data representation formats for the traditional code forms. It agreed these requirements and practices should be separated from the data representation and recommends placing them in an Attachment to Volume 1.2.
3. The last ETDR&C meetings (2002 and 2003) agreed on the difficulty of this task. The Team recommended this activity to be performed under the responsibility of the WMO Secretariat and Dr Cliff Dey was hired as consultant and was given few weeks to work on this subject.
4. Last year a document was presented to the ETDR&C which was going into this direction (see Appendix II). Further work is required to link this new set of regulations with the Templates, which have been defined. The link is perhaps to definemore appropriate Common Sequences.
5. A considerable amount of work is necessary to define the right template in the right order to ease the migration which has to be performed by the data producer and by the data user who will decode the information to feed automatically application programs. If there is flexibility in BUFR and CREX, there is a need of fixed order and formatting for automated operational processing. That is the reason why we have been asked to produce “official” templates, which in a way are becoming themselves regulatory. How to we solve that problem of regulatory format? Ideally there should be a new Volume I.3 Manual, which defines the Templates. We could keep that “virtual” Manual on line in the WMO server.
6. Last year, Dr Cliff Dey had developed a set of regulations for observations disconnecting the reporting practices from the coding in traditional format for some traditional code forms (FM 12, 13, 14, 18, 20, 22, 32, 33), however he had kept the Sections of the traditional code form. For the BUFR Templates a different order of the parameters seems to have been chosen, which might not ease the migration work, but in some case it regroups the same type of data together. A question is asked: What would be the simplest solution for easing the migration? Having the data in the order of the traditional codes would ease the migration, but there might be good reason no to do that. Also, some datum present in Section 3 of traditional SYNOP are not in the present template (like e.g. temperature change, surface pressure change, cloud drift). Should we consider that?
7. Some work has been done to attempt to define this part of Volume 3 for SYNOP, template. The original order of sections for the traditional SYNOP is listed first , then the Template is listed. Then the necessary corresponding Regulations of the Volume I.1 are indicated. New “regulations” parts are indicated in italics. Is that sufficient to define the reporting of the SYNOP? This has to be tested, for example by somebody who has to program an automatic encoding.
8. Obviously still more work has to be done in that direction and still more common sequences need to be defined to have only one descriptor in the description section.
APPENDIX
Order from traditional SYNOP:
FM 12 SYNOP
12.2 Section 1
12.3 Section 2
12.4 Section 3
12.5 Section 4
12.6 Section 5
Section 1:
12.2.1 Type of station
12.2.2 Base of lowest cloud
12.2.3 Visibility
12.2.4 Total cloud cover
12.2.5 Wind direction and speed
12.2.6 Temperature
12.2.7 Dew-point or relative humidity
12.2.8 Sea level pressure or geopotential height
12.2.9 Pressure tendency
12.2.10 Station pressure
12.2.11 Precipitation
12.2.12 Present and past weather
12.2.13 Cloud amount
12.2.14 Cloud type
12.2.15 Observation time
Section 2:
12.3.1 Sea surface temperature
12.3.2 Period and height of waves
12.3.3 Direction, period and height of swell waves
Section 3:
12.4.1 Maximum and minimum temperature
12.4.2 State of ground and total depth of snow
12.4.3 Daily evaporation or evapotranspiration
12.4.4 Temperature change
12.4.5 Duration of sunshine and radiation data
12.4.6 Cloud drift
12.4.7 Cloud genus, direction, and elevation
12.4.8 Amount and duration of period of precipitation
12.4.9 24-hour precipitation
12.4.10 Cloud amount, genus, and height
Section 4:
12.5.1 Clouds below station level
Section 5:
Groups in Section 5 are to be developed nationally
BUFR TEMPLATE FOR SYNOP DATA
3 01 004 / 0 01 001 / WMO block number II / Numeric, 0
0 01 002 / WMO station number iii / Numeric, 0
0 01 015 / Station or site name / CCITT IA5, 0
0 02 001 / Type of station (ix) / Code table, 0
Time of observation
3 01 011 / 0 04 001 / Year / Year, 0
0 04 002 / Month / Month, 0
0 04 003 / Day YY / Day, 0
3 01 012 / 0 04 004 / Hour GG / Hour, 0
0 04 005 / Minute gg / Minute, 0
3 01 021 / 0 05 001 / Latitude (high accuracy) / Degree, 5
0 06 001 / Longitude (high accuracy) / Degree, 5
0 07 030 / Height of station ground above mean sea level / m, 1
0 07 031 / Height of barometer above mean sea level / m, 1
3 02 030 / Pressure data
3 02 001 / 0 10 004 / Pressure P0P0P0P0 / Pa, –1
0 10 051 / Pressure reduced to mean sea level PPPP / Pa, –1
0 10 061 / 3-hour pressure change ppp / Pa, –1
0 10 063 / Characteristic of pressure tendency a / Code table, 0
0 07 004 / Pressure (standard level) a3 / Pa, –1
0 10 009 / Geopotential height of the standard level hhh / gpm, 0
3 02 031 / Basic synoptic “instantaneous” data
Temperature and humidity data
0 07 032 / Height of sensor above local ground
(for temperature measurement) / m, 2
0 12 101 / Temperature/dry-bulb temperature(sc.2) snTTT / K, 2
0 12 103 / Dew-point temperature (scale 2) snTdTdTd / K, 2
0 13 003 / Relative humidity / %, 0
Visibility data
/
0 07 032
/ / Height of sensor above local ground(for visibility measurement) / m, 2
0 20 001 / Horizontal visibility VV / m, –1
Precipitation past 24 hours
0 07 032 /
Height of sensor above local ground
(for precipitation measurement) / m, 20 13 023 / Total precipitation past 24 hours R24R24R24R24 / kg m-2, 1
0 07 032 /
Height of sensor above local ground
(set to missing to cancel the previous value) / m, 2Cloud data
3 02 004 / 0 20 010 / Cloud cover (total) N / %, 0
0 08 002 / Vertical significance / Code table, 0
0 20 011 / Cloud amount (of low or middle clouds) Nh / Code table, 0
0 20 013 / Height of base of cloud h / m, –1
0 20 012 / Cloud type (low clouds CL) CL / Code table, 0
0 20 012 / Cloud type (middle clouds CM) CM / Code table, 0
0 20 012 / Cloud type (high clouds CH) CH / Code table, 0
1 01 000 / Delayed replication of 1 descriptor
0 31001 / Delayed descriptor replication factor / Numeric, 0
3 02 005 / 0 08 002 / Vertical significance / Code table, 0
0 20 011 / Cloud amount (Ns) Ns / Code table, 0
0 20 012 / Cloud type (C) C / Code table, 0
0 20 013 / Height of base of cloud (hshs) hshs / m, -1
3 02 032 / Clouds with bases below station level
1 05 000 / Delayed replication of 5 descriptors
0 31001 / Delayed descriptor replication factor / Numeric, 0
0 08 002 / Vertical significance / Code table, 0
0 20 011 / Cloud amount N’ / Code table, 0
0 20 012 / Cloud type C’ / Code table, 0
0 20 014 / Height of top of cloud H’H’ / m, -1
0 20 017 / Cloud top description Ct / Code table, 0
3 02 033 / State of ground, snow depth, ground minimum temperature
0 20 062 / State of ground (with or without snow) E or E’ / Code table, 0
0 13 013 / Total snow depth sss / m, 2
0 12 113 / Ground minimum temperature (scale2), past 12 hours snTgTg / K, 2
3 02 034 / Basic synoptic “period” data
Present and past weather
0 20 003 / Present weather ww / Code table, 0
0 04 024 / Time period in hours / Hour, 0
0 20 004 / Past weather (1) W1 / Code table, 0
0 20 005 / Past weather (2) W2 / Code table, 0
/ / / Sunshine data
0 04 024 / Time period in hours / Hour, 0
0 14 031 / Total sunshine SSS / Minute, 0
/ Precipitation measurement
0 07 032 / Height of sensor above local ground
(for precipitation measurement) / m, 2
1 02 002 / Replicate next 2 descriptors 2 times
0 04 024 / Time period in hours tR / Hour, 0
0 13 011 / Total precipitation / total water equivalent of snow RRR / kg m-2, 1
Extreme temperature data
0 07 032 / Height of sensor above local ground
(for temperature measurement) / m, 2
0 04 024 / Time period in hours / Hour, 0
0 04 024 / Time period in hours (see Note 1 below) / Hour, 0
0 12 111 / Maximum temperature (scale 2) at height and over period specified snTxTxTx / K, 2
0 04 024 / Time period in hours / Hour, 0
0 12 112 / Minimum temperature (scale 2) at height and over period specified snTnTnTn / K, 2
Wind data
0 07 032 / Height of sensor above local ground
(for wind measurement) / m, 2
0 02 002 / Type for instrumentation for wind measurement
iw / Flag table, 0
0 08 021 / Time significance (= 2 (time averaged)) / Code table, 0
0 04 025 / Time period (= - 10 minutes, or number of minutes after a significant change of wind) / Minute, 0
0 11 001 / Wind direction dd / Degree true, 0
0 11 002 / Wind speed ff / m s-1, 0
0 08 021 / Time significance (= missing value) / Code table, 0
1 03 002 / Replicate next 3 descriptors 2 times
0 04 025 / Time period in minutes / Minute, 0
0 11 043 / Maximum wind gust direction / Degree true, 0
0 11 041 / Maximum wind gust speed 910fmfm, 911fxfx / m s-1, 0
3 02 035 / / Evaporation data
0 04 024 / Time period in hours / Hour, 0
0 02 004 / Type of instrument for evaporation or crop type for evapotranspiration iE / Code table, 0
0 13 033 / Evaporation /evapotranspiration EEE / kg m-2, 1
3 02 036 / / Radiation data
0 04 025 / Time period in minutes / Minute, 0
0 14 002 / Long-wave radiation, integrated over period specified 553SS 4FFFF or 553SS 5FFFF / J m-2, -3
/
0 14 004
/ / Short-wave radiation, integrated over period specified 553SS 6FFFF / J m-2, -30 14 016 / Net radiation, integrated over period specified
553SS 0FFFF or 553SS 1FFFF / J m-2, -4
0 14 028 / Global solar radiation (high accuracy), integrated over period specified 553SS 2FFFF / J m-2, -4
0 14 029 / Diffuse solar radiation (high accuracy), integrated over period specified 553SS 3FFFF / J m-2, -4
0 14 030 / Direct solar radiation (high accuracy), integrated over period specified 55408 4FFFF / J m-2, -4
Notes:
1) Within RA-IV, the maximum temperature at 1200 UTC is reported for the previous calendar day (i.e. the ending time of the period is not equal to the nominal time of the report). To construct the required time range, descriptor 004024 has to be included two times. If the period ends at the nominal time of the report, value of the second 004024 shall be set to 0.
2) If “plain language” text is reported within Section 2, this information can be conveyed in BUFR via the use of an appropriate 205YYY field as an extra descriptor following the above basic template.
Regulations:
Pressure data
Pressure at the station level, in tenths of a hectopascal: