BUFR/CREX Table B - Classification of elements

Transcription

1 - ver TABLES RELATIVE TO SECTION 3 / Table B - Classification of elements F X Class Comments 0 00 / table entries 0 01 Identification Identifies origin and type of data 0 02 Instrumentation Defines instrument types used 0 03 Reserved 0 04 Location (time) Defines time and time derivatives 0 05 Location (horizontal - 1) Defines geographical position, including horizontal derivatives, in association with Class 06 (first dimension of horizontal space) 0 06 Location (horizontal - 2) Defines geographical position, including horizontal derivatives, in association with Class 05 (second dimension of horizontal space) 0 07 Location (vertical) Defines height, altitude, pressure level, including vertical derivatives of position 0 08 Significance qualifiers Defines special character of data 0 09 Reserved 0 10 Non-coordinate location (vertical) Height, altitude, pressure and derivatives observed or measured, not defined as a vertical location 0 11 Wind and turbulence Wind speed, direction, etc Temperature 0 13 Hydrographic and hydrological Humidity, rainfall, snowfall, etc. elements 0 14 Radiation and radiance 0 15 Physical/chemical constituents 0 19 Synoptic features 0 20 Observed phenomena Defines present/past weather, special phenomena, etc Radar data 0 22 Oceanographic elements 0 23 Dispersal and transport 0 24 Radiological elements 0 25 Processing information 0 26 Non-coordinate location (time) Defines time and time derivatives that are not coordinates 0 27 Non-coordinate location Defines geographical positions, in conjunction with Class 28, (horizontal - 1) that are not coordinates 0 28 Non-coordinate location Defines geographical positions, in conjunction with Class 27, (horizontal - 2) that are not coordinates 0 29 Map data 0 30 Image 0 31* Data description operator Elements used in conjunction with data description qualifiers operators 0 33 Quality information 0 35 Data monitoring information 0 40 Satellite data * This class does not exist in. I.2 / Table B 1

2 - ver (/ Table B - continued) Notes: (1) Where a code table or flag table is appropriate, code table or flag table, respectively is entered in the UNITS column. (2) The code tables and flag tables associated with Table B are numbered to correspond with the F, X and Y part of the table reference. (3) To encode values into, the data (with units as specified in the UNIT column) must be multiplied by 10 to the power SCALE. Then subtract the REFERENCE VALUE to give the coded value found in Section 4 of the message. For example, a measured latitude is degrees. The coarse accuracy descriptor is and the encoded value is x 10 2 ( 9000) = (4) Where UNITS are given as CCITT IA5, data shall be coded as character data left justified within the field width indicated using CCITT International Alphabet No. 5, and blank filled to the full field width indicated. (5) Classes 48 to 63 are reserved for local use; all other classes are reserved for future development. (6) Entries 192 to 255 within all classes are reserved for local use. (7) The use of local descriptors, as defined in Notes 5 and 6, in messages intended for non-local or international exchange is strongly discouraged. They should be kept to the barest minimum possible and must also be by-passed by the use of descriptor 2 06 YYY. (8) First-order statistics are included in Table B only when they are produced, as such, by the observing system. (9) In all flag tables within the specification, bits are numbered from 1 to N from the most significant to least significant within a data of N bits, i.e. bit No.1 is the leftmost and bit No. N is the rightmost bit within the data width. The bit No. N (least significant bit) is set to 1 only if all the bits are set to 1 within the data width of the flag table to represent a missing value. I.2 / Table B 2

3 Class 00 - /* table entries I.2 / Table B/00 1 F* X Y VALUE (Bits) (Characters) Table A: entry CCITT IA Character Table A: data category description, line Table A: data category description, line 2 CCITT IA Character 0 32 CCITT IA Character / Master table (see Note 1) CCITT IA Character / edition number CCITT IA Character Master table version number (see Note 2) Master table version number (see Note 3) Local table version number (see Note 4) CCITT IA Character 0 2 CCITT IA Character 0 2 CCITT IA Character F descriptor to be added or defined CCITT IA Character X descriptor to be added or defined CCITT IA Character Y descriptor to be added or defined CCITT IA Character Element name, line 1 CCITT IA Character Element name, line 2 CCITT IA Character Units name CCITT IA Character Units scale sign CCITT IA Character Units scale CCITT IA Character Units reference sign CCITT IA Character Units reference value CCITT IA Character Element data width CCITT IA Character Code figure CCITT IA Character Code figure meaning CCITT IA Character 0 62

4 I.2 / Table B/00 2 (Class 00 - continued) F* X Y VALUE (Bits) (Characters) Bit number CCITT IA Character Bit number meaning CCITT IA Character Descriptor defining sequence CCITT IA Character 0 6 * For descriptors F = B, not 0. Notes: (1) Master tables are described in Note 2 to Section 1 of the regulations (part of the regulation entitled "Specifications of octet contents"). (2) master table version numbers are described in Notes 2 and 4 to Section 1 of regulations edition 3, and in Notes 2 and 5 to Section 1 of regulations edition 4. (3) master table version numbers are described in Note 5 to Section 1 of regulations. (4) For local table version number, see last part of Note 2 to Section 1 of regulations.

5 Class 01 -/ Identification I.2 / Table B/ WMO block number Numeric Numeric WMO station number Numeric Numeric WMO Region number/geographical area Code table Code table WMO Region sub-area (see Note 9) Numeric Numeric Buoy/platform identifier Numeric Numeric Aircraft flight number CCITT IA Character Satellite identifier Code table Code table Aircraft registration number or other identification CCITT IA Character Type of commercial aircraft CCITT IA Character Stationary buoy platform identifier; e.g. C-MAN buoys CCITT IA Character Ship or mobile land station identifier CCITT IA Character Direction of motion of moving observing platform * Speed of motion of moving observing platform* degree true degree true 0 3 m s m s Platform drift speed (high precision) m s m s Station or site name CCITT IA Character Short station or site name CCITT IA Character Long station or site name CCITT IA Character WMO Region sub-area Numeric Numeric Synoptic feature identifier Numeric Numeric Name of feature (see Note 11) CCITT IA Character 0 28 * Descriptors and may relate to parameters of various meanings and the corresponding values may be integrated on different periods.

6 I.2 / Table B/01 2 (Class 01 - continued) Observation sequence number Numeric Numeric Wind speed source Code table Code table Storm identifier (see Note 1) CCITT IA Character WMO storm name* CCITT IA Character WMO long storm name* CCITT IA Character Aerosol optical depth (AOD) source Code table Code table SSI source Code table Code table Numerical model identifier (see Note 13) Identification of originating/ generating centre (see Note 10) Generating application Code table defined by originating/ generating centre (Notes 3, 4 and 5) Identification of originating/ generating centre Identification of originating/ generating sub-centre CCITT IA Character 0 16 Code table Code table 0 5 Common Code table C-1 Common Code table C Originating centre Common Code table C Agency in charge of operating the observing platform Code table Common Code table C Common Code table C Common Code table C Code table Code table 0 7 * Descriptor should be used instead of to encode this element.

7 (Class 01 - continued) I.2 / Table B/ SIGMET sequence identifier CCITT IA Character Source of sea ice fraction Code table Code table Graphical Area Forecast (GFA) sequence identifier CCITT IA Character Absolute platform velocity - first component (see Note 6) Absolute platform velocity - second component (see Note 6) Absolute platform velocity - third component (see Note 6) m s m s m s m s m s m s Platform transmitter ID number Numeric Numeric Platform transmitter ID number CCITT IA Character Platform transmitter ID Code table Code table Tsunameter report sequence number triggered by a tsunami event Numeric Numeric Aircraft reporting point (Beacon identifier) CCITT IA Character Short ICAO location indicator CCITT IA Character ICAO location indicator CCITT IA Character Runway designator CCITT IA Character ICAO region identifier CCITT IA Character Tide station identification CCITT IA Character Ship line number according to SOOP CCITT IA Character Radiosonde serial number CCITT IA Character Radiosonde ascension number (see Note 12) Numeric Numeric Radiosonde release number (see Note 12) Numeric Numeric Observing platform manufacturer's model CCITT IA Character 0 20 FM 94 FM 95

8 I.2 / Table B/01 4 (Class 01 - continued) Observing platform manufacturer's serial number WMO marine observing platform extended identifier Technique for making up initial perturbations CCITT IA Character 0 32 Numeric Numeric 0 7 Code table Code table Ensemble member number Numeric Numeric Type of ensemble forecast Code table Code table Balloon lot number CCITT IA Character WBAN number Numeric Numeric Observer identification CCITT IA Character Station acquisition CCITT IA Character Unique product definition CCITT IA Character State identifier Code table Code table National station number Numeric Numeric Aircraft tail number CCITT IA Character Origination airport CCITT IA Character Destination airport CCITT IA Character Grid point identifier Numeric Numeric Snapshot identifier Numeric Numeric 0 10 Notes: (1) The storm identifier (descriptor ) has the following meaning: the first two characters shall be a numeric sequence number assigned by the originator of the message; the third character is a letter indicating the ocean basin where the storm is located, as follows: W NW Pacific Ocean E NE Pacific Ocean to 140 W C NE Pacific Ocean 140 W 180 W

9 I.2 / Table B/01 5 (Class 01 - continued) L N Atlantic Ocean, including Caribbean and Gulf of Mexico A N Arabian Sea B Bay of Bengal S S Indian Ocean P S Pacific Ocean F RSMC Nadi's zone in South Pacific U Australia O South China Sea T East China Sea There is no requirement that differing observers coordinate sequence numbers even though they both may be reporting the same storm. (2) WMO long storm name (descriptor ): the storm name "Nameless" shall be used in those cases where an identifiable tropical disturbance has not reached tropical storm strength and has not been assigned an official name. (3) Where a centre other than the originating centre generates quality information, replacement or substitute values, and/or statistical information, the centre may be indicated by using (4) A generating centre may wish to indicate a reference to the application that generated quality information, etc.; it may use descriptor for this purpose. However, the corresponding code tables will vary from centre to centre. (5) Code table is to be generated by each centre. (6) The components of absolute platform velocity ( , , ) are defined as follows: First component: From the Earth s centre to 0 degree longitude at the Equator: velocity of the platform along this line relative to the Earth s centre. Second component: From the Earth s centre to 90 degrees East longitude at the Equator: velocity of the platform along this line relative to the Earth s centre. Third component: From the Earth s centre to the north pole: velocity of the platform along this line relative to the Earth s centre. (7) The values for descriptors , and have been chosen to be suitable for polar orbiting satellites in approximately Sun-synchronous orbits. Geostationary orbits would require greater data widths for distance and slightly less for speed. (8) Left handed x, y and z axes have been chosen for descriptors , and (9) Descriptor should be used instead of for encoding this element. (10) Descriptor shall be used instead of descriptor for encoding originating/generating centre. Code table is to be established by the associated originating/generating centre identified by descriptor and provided to the Secretariat for publication. (11) For , the character string representing the Name of feature should be of the form: Type of phenomenon Location or geographical name (e.g. volcano Popocatepetl, oil fire Kuwait ).

10 I.2 / Table B/01 6 (Class 01 - continued) (12) Descriptor is to be used for reporting the sequential number of the current radiosonde reporting period (e.g. synoptic cycle) within a given year or other similar locally defined length of time. Descriptor is to be used in the case of multiple sequential radiosonde releases during a single reporting period (e.g. synoptic cycle), in order to indicate which particular release generated the corresponding data values. (13) The value of this feature could be a string of characters, which contain the name of the model and other useful elements such as the model mesh. (14) Stationary position of ship shall be reported by set to 0 and set to 0. Course of ship unknown (D s = 9) shall be reported by set to 509.

11 Class 02 - / Instrumentation I.2 / Table B/ Type of station Code table Code table Type of instrumentation for wind measurement Flag table Flag table Type of measuring equipment used Code table Code table Type of instrumentation for Code table Code table 0 2 evaporation measurement or type of crop for which evapotranspiration is reported Precision of temperature observation K K Radiosonde type Code table Code table Radiosonde computational method Code table Code table Solar and infrared radiation correction Code table Code table Tracking technique/status of Code table Code table 0 3 system used Radiosonde completeness Code table Code table Radiosonde configuration Flag table Flag table Correction algorithms for humidity Code table Code table 0 2 measurements Satellite instruments Code table Code table Satellite classification Code table Code table Satellite instrument data used Flag table Flag table 0 3 in processing* Satellite data-processing technique Flag table Flag table 0 3 used Satellite-derived wind computation method Code table Code table 0 2 * Descriptor should be used instead of for encoding this element.

12 I.2 / Table B/02 2 (Class 02 - continued) Integrated mean humidity computational method Code table Code table Satellite channel(s) used in computation Flag table Flag table Cross-track resolution m m Along-track resolution m m Segment size at nadir in x-direction m m Segment size at nadir in y-direction m m Method of current measurement Code table Code table Duration and time of current measurement Code table Code table Indicator for digitization Code table Code table Method of salinity/depth measurement Code table Code table Drogue type Code table Code table Cable length m m Buoy type Code table Code table Method of tidal observation Code table Code table Method of water temperature and/or salinity measurement Method of wet-bulb temperature measurement Method of removing velocity and motion of platform from current Method for estimating reports related to synoptic features Code table Code table 0 2 Code table Code table 0 1 Code table Code table 0 2 Code table Code table Indicator for sea-surface current speed Code table Code table Indicator for method of calculating spectral wave data Code table Code table 0 2

13 (Class 02 - continued) I.2 / Table B/ Indicator for type of platform Code table Code table Wave measurement instrumentation Code table Code table Deep-ocean tsunameter type Code table Code table Satellite sensor indicator Code table Code table Geostationary satellite data-processing technique used Flag table Flag table Geostationary sounder satellite channels used Flag table Flag table Indicator to specify observing method for extreme temperatures Code table Code table Geostationary imager satellite channels used Flag table Flag table GOES-I/M brightness temperature characteristics Code table Code table GOES-I/M soundings parameter characteristics Code table Code table Geostationary soundings statistical parameters Code table Code table Geostationary soundings accuracy statistics Code table Code table Origin of first-guess information for GOES-I/M soundings Valid times of first-guess information for GOES-I/M soundings Origin of analysis information for GOES-I/M soundings Origin of surface information for GOES-I/M soundings Code table Code table 0 2 Code table Code table 0 2 Code table Code table 0 2 Code table Code table Aircraft navigational system Code table Code table Type of aircraft data relay system Code table Code table Aircraft roll angle Aircraft roll angle quality Code table Code table 0 1

14 I.2 / Table B/02 4 (Class 02 - continued) ACARS ground-receiving station CCITT IA Character Radiosonde ground receiving system Code table Code table Radiosonde operating frequency Hz Hz Original specification of latitude/longitude Code table Code table Spectrographic wavelength m m Spectrographic width m m Balloon manufacturer Code table Code table Type of balloon Code table Code table Weight of balloon kg kg Type of balloon shelter Code table Code table Type of gas used in balloon Code table Code table Amount of gas used in balloon kg kg Balloon flight train length m m Entry sensor 4/20 ma A A Type of pressure sensor Code table Code table Type of temperature sensor Code table Code table Type of humidity sensor Code table Code table Polarization Code table Code table Radar constant* db db Type of antenna Code table Code table Antenna height above tower base m m Radome Flag table Flag table 0 1 * This constant is defined as follows: Z = P + radar constant where Z = the reflectivity of target in beam direction (dbz); P = the input receiver power above 1 mw (dbm). This constant is used to normalize the signal to the equivalent 100 km range.

15 (Class 02 - continued) I.2 / Table B/ Antenna polarization Code table Code table Maximum antenna gain db db dB beamwidth Sidelobe suppression db db Crosspol discrimination (on axis) db db Antenna speed (azimuth) degree/s degree/s Antenna speed (elevation) degree/s degree/s Radar incidence angle Radar look angle Number of azimuth looks Numeric Numeric Antenna effective surface area m m Type of surface observing equipment Code table Code table Percentage of 320 MHz band processed Percentage of 80 MHz band processed Percentage of 20 MHz band processed % % 0 3 % % 0 3 % % RA-2 instrument operations Code table Code table Ocean wave frequency Hz Hz Mean frequency Hz Hz Frequency agility range Hz Hz Peak power W W Average power W W Pulse repetition frequency Hz Hz Pulse width s s 7 2

16 I.2 / Table B/02 6 (Class 02 - continued) Receiver intermediate frequency Hz Hz Intermediate frequency bandwidth Hz Hz Minimum detectable signal db db Dynamic range db db Sensitivity time control (STC) Flag table Flag table Azimuth pointing accuracy Elevation pointing accuracy Antenna beam azimuth Antenna elevation Range processed by range attenuation correction m m Radar dual PRF ratio Code table Code table Antenna rotation direction Code table Code table Satellite radar beam azimuth angle Measurement type (see Note 4) CCITT IA Character Ozone instrument serial number/ identification (see Note 5) CCITT IA Character Ozone instrument type Code table Code table Light source type for Brewer spectrophotometer Wave length setting for Dobson instruments Source conditions for Dobson instruments Code table Code table 0 2 Code table Code table 0 2 Code table Code table Data collection and/or location system Code table Code table Type of data buoy Code table Code table 0 2

17 (Class 02 - continued) I.2 / Table B/ TOVS/ATOVS/AVHRR instrumentation channel number Code table Code table Radiometer identifier Code table Code table Satellite instrument used in data processing (see Note 6) Flag table Flag table Satellite channel centre frequency Hz Hz Satellite channel band width Hz Hz Satellite channel wavelength m m Percentage of valid KU ocean retracker measurements % % Percentage of valid S ocean retracker measurements % % RA-2 instrument Flag table Flag table MWR instrument Flag table Flag table Wave length of the radar Code table Code table Height assignment method Code table Code table Tracer correlation method Code table Code table Radiance type flags Flag table Flag table Radiance type Code table Code table Radiance computational method Code table Code table Hydrostatic pressure of lower end of cable (thermistor string) Pa kpa Anemometer type Code table Code table Aircraft humidity sensors Code table Code table Product type for retrieved atmospheric gases Code table Code table Square of the off-nadir angle (see Note 7) degree degree Mean across track pixel number Numeric Numeric Method of precipitation measurement Code table Code table Method of state of ground measurement Code table Code table Method of snow depth measurement Code table Code table 0 2

18 I.2 / Table B/02 8 (Class 02 - continued) Method of liquid content measurement of precipitation Code table Code table Type of sky condition algorithm Code table Code table Main present weather detecting system Code table Code table Supplementary present weather sensor Flag table Flag table Visibility measurement system Code table Code table Cloud detection system Code table Code table Type of lightning detection sensor Code table Code table Method of evaporation measurement Code table Code table Capability to detect precipitation phenomena Capability to detect other weather phenomena Flag table Flag table 0 10 Flag table Flag table Capability to detect obscuration Flag table Flag table Capability to discriminate lightning strikes Lagrangian drifter submergence (% time submerged) Flag table Flag table 0 4 % % Geopotential height calculation Code table Code table 0 2 Notes: (1) This class shall contain elements to describe the instrumentation used to obtain the meteorological elements reported. (2) This class may also contain elements relating to observational procedures. (3) Some indication of expected accuracy may be implied in conjunction with certain elements in this class. (4) Note that descriptor is the azimuth angle measured anticlockwise from satellite heading vector. (5) In descriptor : Ozone instrument serial number/identification is four characters long. For Japanese Dobsons instruments, omit the leading digit(s). (6) Descriptor should be used instead of descriptor for single satellite instrument identification. (7) Square of off-nadir angle computed from Ku waveform-derived parameters, Unit 10 4 deg 2, Common minimum value 0, Common maximum value 900.

19 Class 04 - / Location (time) I.2 / Table B/ Year a a Month mon mon Day d d Hour h h Minute min min Second s s Seconds within a minute (microsecond accuracy) s s Time increment a a Time increment mon mon Time increment d d Time increment h h Time increment min min Time increment s s Reference time period for accumulated or extreme data min min Time period or displacement a a Time period or displacement mon mon Time period or displacement d d Time period or displacement h h Time period or displacement min min Time period or displacement s s Duration of time relating to following value Duration of time relating to following value h h 0 3 min min 0 2

20 I.2 / Table B/04 2 (Class 04 - continued) Time difference, UTC - LMT (see Note 6) min min Day of the year d d Principal time of daily reading of maximum temperature h h Principal time of daily reading of minimum temperature h h Number of days with precipitation equal to or more than 1 mm Times of observation used to compute the reported mean values Numeric Numeric 0 2 Flag table Flag table Short time increment min min Short time increment s s Short time period or displacement d d Short time period or displacement h h Short time period or displacement min min Averaging period for following value Code table Code table Long time period or displacement s s 0 5 Notes: (1) The significance of time periods or displacements may be indicated using the time significance code corresponding to table reference (2) Where more than one time period or displacement is required to define complex time structures, they shall be defined in immediate succession, and the following ordering shall apply: ensemble period (if required), followed by forecast period (if required), followed by period for averaging or accumulation (if required). (3) Time periods or displacements and time increments require an initial time location to be defined prior to their use, followed where appropriate by a time significance definition. (4) The time location, when used with forecast values, shall indicate the time of the initial state for the forecast, or the beginning of the forecast period; when used with ensemble means of forecast values, the time location shall indicate the initial state or the beginning of the first forecast over which ensemble means are derived. (5) Negative time periods or displacements shall be used to indicate time periods or displacements preceding the currently defined time. (6) Descriptor has been replaced by the combination of and and should not be used for encoding this element. (7) All times are Universal Time Coordinated (UTC) unless otherwise noted.

21 Class 05 - / Location (horizontal - 1) I.2 / Table B/ Latitude (high accuracy) Latitude (coarse accuracy) Latitude increment (high accuracy) Latitude increment (coarse accuracy) Latitude displacement (high accuracy) Latitude displacement (coarse accuracy) Bearing or azimuth degree true degree true Solar azimuth degree true degree true Sun to satellite azimuth difference Direction (spectral) Row number Numeric Numeric Pixel size on horizontal - 1 m m Along track row number Numeric Numeric Maximum size of x-dimension Numeric Numeric Ship transect number according to SOOP Numeric Numeric Orbit number Numeric Numeric Scan line number Numeric Numeric Channel number Numeric Numeric Field of view number Numeric Numeric Satellite cycle number Numeric Numeric Field of regard number Numeric Numeric Channel number increment Numeric Numeric Field of view number increment Numeric Numeric Y angular position from centre of gravity Z angular position from centre of gravity

22 I.2 / Table B/05 2 (Class 05 - continued) Notes: (1) Values of latitude and latitude increments are limited to the range -90 degrees to +90 degrees. (2) South latitude shall be assigned negative values. (3) North to south increments shall be assigned negative values. (4) Bearing or azimuth shall only be used with respect to a stated location, and shall not redefine that location. (5) The pixel size on horizontal - 1 is given at location where map scale factor is unity.

23 Class 06 - / Location (horizontal - 2) Longitude (high accuracy) Longitude (coarse accuracy) Longitude increment (high accuracy) Longitude increment (coarse accuracy) Longitude displacement (high accuracy) Longitude displacement (coarse accuracy) Distance m m Wave number m m Wave number (spectral) rad m rad m Column number Numeric Numeric Pixel size on horizontal - 2 m m Cross-track cell number Numeric Numeric Maximum size of y-dimension Numeric Numeric Radius of confidence m m 0 4 I.2 / Table B/06 1 Notes: (1) Values of longitude are limited to the range -180 degrees to +180 degrees. (2) West longitude shall be assigned negative values. (3) East to west increments shall be assigned negative values. (4) Distance shall only be used with respect to a stated location and a bearing, azimuth or elevation; it shall not redefine that location. (5) The pixel size on horizontal - 2 is given at location where map scale factor is unity.

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25 Class 07 - / Location (vertical) I.2 / Table B/ Height of station (see Note 1) m m Height or altitude m m Geopotential m 2 s m 2 s Pressure Pa Pa Height increment m m Height above station m m Height m m Geopotential m 2 s m 2 s Geopotential height gpm gpm Flight level m ft Grid point altitude m m Elevation (see Note 2) Solar elevation Satellite zenith angle Solar zenith angle Satellite zenith angle Height of station ground above mean sea level (see Note 3) Height of barometer above mean sea level (see Note 4) m m 1 5 m m Height of sensor above local ground m m 2 5 (or deck of marine platform) (see Note 5) Height of sensor above water surface m m 1 4 (see Note 6) Maximum size of z-dimension Numeric Numeric 0 4

26 I.2 / Table B/07 2 (Class 07 - continued) Level index of z Numeric Numeric Impact parameter (see Note 7) m m Depth below land surface m m Depth below sea/water surface m m Depth below sea/water surface (cm) m m Representative height of sensor above station (see Note 8) m m Water pressure Pa Pa Drogue depth m m 0 4 Notes: (1) Regarding data from ground-based stations, this descriptor should be used for archived data only. Descriptors and should be used and preferred to represent ground elevation and elevation of barometer, respectively, as defined in Weather Reporting (WMO-No. 9), Volume A Observing Stations. Regarding marine stations, this descriptor refers to the height above mean sea level of the deck of marine platform where the instruments stand. (2) Elevation shall only be used with respect to a stated location and a bearing, azimuth or distance; it shall not redefine that location. (3) Height of station ground above mean sea level is defined as the height above mean sea level of the ground on which the raingauge stands or, if there is no raingauge, the ground beneath the thermometer screen. If there is neither raingauge nor screen, it is the average level of terrain in the vicinity of the station (Reference: Guide to Meteorological Instruments and Methods of Observation, WMO-No ). (4) Height of barometer above mean sea level, referring to the location of barometer of a station, does not redefine the descriptor (5) Height of sensor above local ground (or deck of marine platform) is the actual height of sensor above ground (or deck of marine platform) at the point where the sensor is located. This descriptor does not redefine the descriptors or Previously defined value of may be cancelled by setting to a "missing value". (6) Height of sensor above water surface is the height of sensor above water surface of sea or lake. This descriptor does not redefine descriptors or Previously defined value may be cancelled by setting to a "missing value". (7) For an atmospheric limb sounder, the impact parameter is the distance between the ray asymptote and the centre of curvature of the Earth s surface at the tangent point. (8) Representative height of sensor above station is the standard height of a sensor required by WMO documentation. The value of the following meteorological element should be adjusted using a formula. For example, standard height recommended in WMO documentation for surface wind sensors is 10 metres. If the sensor is placed at a different height, the wind speed may be adjusted using a formula.

27 Class 08 - / Significance qualifiers I.2 / Table B/ Vertical sounding significance Flag table Flag table Vertical significance (surface observations) Vertical significance (satellite observations) Code table Code table 0 2 Code table Code table Phase of aircraft flight Code table Code table Meteorological attribute significance Code table Code table Ozone vertical sounding significance Flag table Flag table Dimensional significance Code table Code table Radiation vertical sounding significance Flag table Flag table Detailed phase of flight Code table Code table Surface qualifier (temperature data) Code table Code table Meteorological feature Code table Code table Land/sea qualifier Code table Code table Day/night qualifier Code table Code table Qualifier for runway visual range Code table Code table Change qualifier of a trend-type forecast or an aerodrome forecast Qualifier of the time when the forecast change is expected Code table Code table 0 1 Code table Code table SEAWINDS land/ice surface type Flag table Flag table Qualifier for following centre identifier Code table Code table Total number of missing entities Numeric Numeric 0 5 (with respect to accumulation or average) Time significance Code table Code table 0 2

28 I.2 / Table B/08 2 (Class 08 - continued) Total number (with respect to Numeric Numeric 0 5 accumulation or average) First-order statistics Code table Code table Difference statistics Code table Code table Time difference qualifier (see Note 5) Code table Code table Matrix significance Code table Code table Surface type Code table Code table Manual on Codes (Volume I.1, Numeric Numeric 0 4 Section C) Code table from which data are derived Data category - table A Numeric Numeric Method of derivation of percentage Code table Code table 0 3 confidence (see Note 6) Type of monitoring exercise Code table Code table Type of centre or station performing Code table Code table 0 1 monitoring Time significance (Aviation forecast) Code table Code table Flight level significance Code table Code table Data significance Code table Code table Extended vertical sounding Flag table Flag table 0 6 significance Atmospheric chemical or physical Code table Code table 0 3 constituent type Atmospheric chemical or physical Common Code Common Code 0 5 constituent type table C-14 table C Number of observations Numeric Numeric Qualifier for number of missing values in calculation of statistic Code table Code table 0 2

29 (Class 08 - continued) I.2 / Table B/ Qualifier for number of missing values in calculation of statistic Condition for which number of days of occurrence follows Code table Code table 0 1 Code table Code table Day of occurrence qualifier Code table Code table Qualifier for wind speed or wind gusts Code table Code table Sample scanning mode significance Code table Code table Sun-glint indicator Code table Code table Semi-transparency indicator Code table Code table TOVS/ATOVS product qualifier Code table Code table Pixel(s) type Code table Code table Altimeter echo type Code table Code table Ascending/descending orbit qualifier Code table Code table Type of band Code table Code table Radiometer sensed surface type Code table Code table Product status Code table Code table Qualifier for GTSPP quality flag Code table Code table Type of equipment Code table Code table Modification of sensor height to another value Code table Code table Nominal value indicator Flag table Flag table Beam identifier Code table Code table Vertical significance for NWP Flag table Flag table Decimal scale of following significands Numeric Numeric 0 3

30 I.2 / Table B/08 4 (Class 08 - continued) Notes: (1) Where values are accumulated or averaged (for example over a time period), the total number of values from which the accumulated or averaged values are obtained may be represented using reference (2) A previously defined significance may be cancelled by transmitting a missing from the appropriate code or flag table. (3) First-order statistics have values with a similar range and the same dimensions as the corresponding reported values (e.g., maxima, minima, means). (4) Difference statistics are difference values; they have dimensions similar to the corresponding reported values with respect to units, but assume a range centred on zero (e.g. the difference between reported and analysed values, the difference between reported and forecast values). (5) Descriptor is to be used with (time difference). (6) Descriptor is to be used by preceding the element as part of quality control information in order to specify the method used to calculate the percentage confidence. (7) When descriptor is used to specify particulate matter (PM) under a given size threshold, descriptor may also be used to further specify a subset of the PM population on the basis of ion composition. (8) Descriptor is to be used to establish the decimal scale of one or more subsequent numerical element descriptors requiring a large dynamic range of values. The numerical element descriptor(s) will contain the scaled value of the measurement(s) with the required number of significant digits. The actual value will be obtained, at the application level, by multiplying the scaled value by the given decimal scale: (scaled value x 10 decimal scale ).

31 Class 10 - / Non-coordinate location (vertical) I.2 / Table B/ Height of land surface m m Height m m Geopotential m 2 s m 2 s Pressure Pa Pa Height m m Geopotential m 2 s m 2 s Geopotential height gpm gpm Minimum pressure reduced to mean sea level Maximum pressure reduced to mean sea level Pa Pa -1 5 Pa Pa In direction of the North Pole, m m 2 10 distance from the Earth's centre (see Notes 2 and 3) Satellite distance to Earth's centre m m Altitude (platform to ellipsoid) m m Earth's radius m m Earth's local radius of curvature m m Geoid undulation (see Note 4) m m Number of retrieved layers Numeric Numeric Standard deviation altitude m m Pressure reduced to mean sea level Pa Pa Altimeter setting (QNH) Pa Pa Global navigation satellite system m m 0 5 altitude Pressure change Pa Pa hour pressure change Pa Pa -1 4

32 I.2 / Table B/10 2 (Class 10 - continued) hour pressure change Pa Pa Characteristic of pressure tendency Code table Code table SIGMET cruising level Code table Code table Indicated aircraft altitude m m Viewing zenith angle Altitude of COG above reference ellipsoid m m Instantaneous altitude rate m s m s Squared off nadir angle of the satellite from platform data Squared off nadir angle of the satellite from waveform data degree degree degree degree Mean sea surface height m m Geoid's height m m Ocean depth/land elevation m m Total geocentric ocean tide height (solution 1) Total geocentric ocean tide height (solution 2) m m 3 5 m m Long period tide height m m Tidal loading height m m Solid Earth tide height m m Geocentric pole tide height m m Height of atmosphere used m m Mean dynamic topography m m Mean sea surface height from altimeter only m m 3 6

33 (Class 10 - continued) Loading tide height geocentric ocean tide solution Loading tide height geocentric ocean tide solution Non-equilibrium long period tide height Squared off nadir angle of the satellite from waveform data m m 4 4 m m 4 4 m m 4 4 degree degree Sea surface height anomaly m m 3 5 Notes: (1) Vertical elements and pressure shall be used to define values of these elements independent of the element or variable denoting the vertical coordinate. (2) The value for descriptor has been chosen to be suitable for polar orbiting satellites in approximately Sun-synchronous orbits. Geostationary orbits would require greater data widths for distance and slightly less for speed. (3) Left handed x, y and z axes have been chosen for descriptor (4) The geoid undulation is the difference between the reference ellipsoid (WGS-84) and the geoid height (EGM96) at the geographic location of the observation, both referenced to the centre of mass of the Earth. I.2 / Table B/10 3

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35 Class 11 - / Wind and turbulence I.2 / Table B/ Wind direction degree true degree true Wind speed m s m s u-component m s m s v-component m s m s w-component Pa s Pa s w-component m s m s Wind direction associated with wind speed which follows degree true degree true Wind direction at 10 m degree true degree true Wind speed at 10 m m s m s Wind direction at 5 m degree true degree true Wind speed at 5 m m s m s Extreme counterclockwise wind direction of a variable wind Extreme clockwise wind direction of a variable wind degree true degree true 0 3 degree true degree true Steadiness of wind (see Note 6) % % Relative vorticity s s Divergence s s Velocity potential m 2 s m 2 s Extended degree of turbulence Code table Code table Degree of turbulence Code table Code table Height of base of turbulence m m Height of top of turbulence m m Vertical gust velocity m s m s Vertical gust acceleration m s m s 2 2 5