MADIS Radiosonde Variables

MADIS Radiosonde Variables - Numeric

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Code       Name               Max Number       Units      Max          Notes      Database  
                               of Levels               QC Level*                 FSL  AWIPS 
-------------------------------------------------------------------------------------------


Integrated Sounding              405                    Sig   Man        1      
-------------------                                     ---   ---

DD        wind direction                       deg       1     2         2        X     X
FF        wind speed                           m/s       1     2         2        X     X
U         u wind component                     m/s       1     2         2        X     X
V         v wind component                     m/s       1     2         2        X     X
T         air temperature                      K         2     2         3,4      X     X
TV        virtual temperature                  K         2     2         3,4      X     X
TD        dewpoint temperature                 K         1     1         5        X     X
RH        relative humidity                    %         1     1         5        X     X
Q         specific humidity                    kg/kg     1     1         5        X     X
DPD       dewpoint depression                  K         1     1         5        X     X
AH        absolute humidity                    g/(m**3)  1     1         5        X     X
WVMR      water vapor mixing ratio             kg/kg     1     1         5        X     X
P         pressure                             Pa        1     1                  X     X
HT        geopotential height                  m         1     2         3        X     X
LEVTYPE   level type                           code      0     0         6        X     X


Mandatory Levels                  22                                     1            
----------------

DDMAN     wind direction                       deg       2               2        X     X
FFMAN     wind speed                           m/s       2               2        X     X
UMAN      u wind component                     m/s       2               2        X     X
VMAN      v wind component                     m/s       2               2        X     X
TMAN      air temperature                      K         2               3,4      X     X
TVMAN     virtual temperature                  K         2               3,4      X     X
TDMAN     dewpoint temperature                 K         1               5        X     X
RHMAN     relative humidity                    %         1               5        X     X
QMAN      specific humidity                    kg/kg     1               5        X     X
DPDMAN    dewpoint depression                  K         1               5        X     X
AHMAN     absolute humidity                    g/(m**3)  1               5        X     X
WVMRMAN   water vapor mixing ratio             kg/kg     1               5        X     X
PMAN      pressure                             Pa        1                        X     X
HTMAN     geopotential height                  m         2               3        X     X


Significant Levels               175                                     1           
------------------

TSIG      air temperature                      K         2               4        X     X
TVSIG     virtual temperature                  K         2               4        X     X
TDSIG     dewpoint temperature                 K         1               5        X     X
RHSIG     relative humidity                    %         1               5        X     X
QSIG      specific humidity                    kg/kg     1               5        X     X
DPDSIG    dewpoint depression                  K         1               5        X     X
AHSIG     absolute humidity                    g/(m**3)  1               5        X     X
WVMRSIG   water vapor mixing ratio             kg/kg     1               5        X     X
PSIG      pressure                             Pa        1                        X     X
HTSIG     geopotential height                  m         1               1        X     X


Wind Levels                      200                                     1        
-----------

DDWIND    wind direction                       deg       1               2        X     X
FFWIND    wind speed                           m/s       1               2        X     X
UWIND     u wind component                     m/s       1               2        X     X
VWIND     v wind component                     m/s       1               2        X     X
PWIND     pressure                             Pa        1               1        X     X
HTWIND    geopotential height                  m         1                        X     X


Maximum Wind Levels                4                                     1             
-------------------

DDMXWND   wind direction                       deg       1               2        X     X
FFMXWND   wind speed                           m/s       1               2        X     X
UMXWND    u wind component                     m/s       1               2        X     X
VMXWND    v wind component                     m/s       1               2        X     X
PMXWND    pressure                             Pa        1                        X     X
HTMXWND   geopotential height                  m         1               1        X     X


Tropopause Levels                  4                                     1             
-----------------

DDTROP    wind direction                       deg       1               2        X     X
FFTROP    wind speed                           m/s       1               2        X     X
UTROP     u wind component                     m/s       1               2        X     X
VTROP     v wind component                     m/s       1               2        X     X
TTROP     air temperature                      K         2               4        X     X
TVTROP    virtual temperature                  K         2               4        X     X
TDTROP    dewpoint temperature                 K         1               5        X     X
RHTROP    relative humidity                    %         1               5        X     X
QTROP     specific humidity                    kg/kg     1               5        X     X
DPDTROP   dewpoint depression                  K         1               5        X     X
AHTROP    absolute humidity                    g/(m**3)  1               5        X     X
WVMRTROP  water vapor mixing ratio             kg/kg     1               5        X     X
PTROP     pressure                             Pa        1                        X     X
HTTROP    geopotential height                  m         1               1        X     X


Station Identification
----------------------

SONDET    sonde type                           code      0               7        X

MADIS Radiosonde Variables - Character

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Code       Name                                Character               Notes
                                               Size
------------------------------------------------------------------------------------------- 
RELTIME   release time                         9                         8        X

Notes

The user can choose to retrieve the different radiosonde level types individually, or can select an integrated sounding that will return all levels combined and sorted in ascending order by height.
- The number of levels in the integrated sounding varies, with values typically between 50 and 125.
- Mandatory levels include the 21 mandatory isobaric levels plus the surface level.
- The pressures returned for wind levels have been calculated using a log(P) interpolation.
- The heights returned for significant, maximum wind, and tropopause levels have been calculated using the hypsometric equation (if temperature is available) or a log(P) interpolation (if temperature is missing).
- If the user wants to easily identify pressure or heights that have been interpolated, without identifying the type of level, he can check for the character "I" in the QC data descriptor.
For more information on the radiosonde level types and variables, see Federal Meteorological Handbook 3 (FMH-3). An HTML version of FMH-3 is available at http://www.ofcm.gov/fmh3/text/default.htm.
Wind speed and direction are reported and stored in the database. The user can optionally select u & v wind components and those will be calculated and returned. The QC results from speed and direction will be used In either case, and if one of the map projections has been selected via the MSETDOM call, the winds will be rotated to match the projection.
The hydrostatic check applied to mandatory level heights and temperatures can, under certain circumstances, decide that a reported value is wrong, and offer a corrected value, which the user is encouraged to use instead of the reported value. The API default is to return the reported value. The MSETCOR call is used to indicate whether or not to use recommended corrections.
Air temperature is the temperature variable stored in the database. The user can optionally select virtual temperature, which will then be calculated by the MADIS API. The QC results from air temperature will apply in either case. Also note that if virtual temperature cannot be calculated (missing or bad dewpoint or pressure), and the air temperature passed all QC checks, the air temperature will be returned instead, and a QC data descriptor value of "T" will be assigned.
Dewpoint depression is the moisture variable reported and stored in the database. The user can optionally select dewpoint temperature, relative humidity, specific humidity, absolute humidity, or water vapor mixing ratio. These values will then be calculated by the MADIS API. The QC results from dewpoint depression will apply to any of the calculated variables.

Level type codes:

       Value      Meaning
       -----      -------
         1        surface
         2        mandatory
         3        significant
         4        wind
         5        maximum wind
         6        tropopause

The coded values for the sonde type are too extensive to list in this document. See table 3685 in Appendix E of FMH-3, which is available at http://www.ofcm.gov/fmh3/text/default.htm.
Not all stations report release time, and the release time for those that do report this value are generally +- 70 minutes from the "synoptic time". The synoptic time is what's reported in the observation time array by the MRAOBSTA subroutine, and this is generally used as the nominal time of the data for most applications (e.g., most times reported for the 00 hour file will also be hour 00).
All times reported in the MADIS API are in Universal Coordinated Time, with the format of "YYJJJHHMM", where:
```
    YY  = 2-digit year (good from 1980 - 2179)
    JJJ = Julian date of the year (1-366)
    HH  = Hour (0-23)

    MM  = Minute (0-59)
```
If the release time is missing, the 9-character field will be set to all blanks, e.g., " ".
Users of the MADIS API raobdump program will get the time output in their chosen format, either YYJJJHHMM or YYYYMMDD_HHMM.

^*The QC information is only available with the FSL database.