MADIS ACARS-Profiles Variables - Numeric
---------------------------------------------------------------------------------------------------
Code       Name                                Units      Max     Notes      Max Number   Database
                                                       QC Level*              of Levels  FSL  AWIPS
---------------------------------------------------------------------------------------------------
                                                            

Profiles                                                            1           200
--------

DD        wind direction                       deg          1       2                     X     X
FF        wind speed                           m/s          1       2                     X     X
U         u wind component                     m/s          1       2                     X     X
V         v wind component                     m/s          1       2                     X     X
T         air temperature                      K            2       3                     X     X
TV        virtual temperature                  kg/kg        2       3                     X     X
TD        dewpoint temperature                 K            2       4                     X     X
RH        relative humidity                    %            2       4                     X     X
Q         specific humidity                    kg/kg        2       4                     X     X
DPD       dewpoint depression                  K            2       4                     X     X
AH        absolute humidity                    g/(m**3)     2       4                     X     X
WVMR      water vapor mixing ratio             g/kg         2       4                     X     X
REPWVQC   reported water vapor QC              code         0       5                     X     X
RH1       rh sensor 1                          %            0      13,14                  X
RH2       rh sensor 2                          %            0      13,14                  X
RHUNCER   rh uncertainty                       %            0      13,14                  X
TDUNCER   dewpoint uncertainty                 K            0      13,14                  X
MEDEDR    median eddy dissipation rate         m**(2/3)/s   1      15,16                  X     
MAXEDR    maximum eddy dissipation rate        m**(2/3)/s   1      15,16                  X     
TURBIDX   turbulence index                     code         1       6,15,16               X     X
HT        pressure altitude                    m            2       7                     X     X
GPSHT     geometric height determined by GPS   m            0      13                     X
BAROHT    barometric-corrected height          m            0       7                     X
P         pressure                             Pa           2       7                     X     X
LAT       track latitude                       deg N        1                             X     X
LON       track longitude                      deg E        1                             X     X
ICECOND   icing condition                      code         1       8,15                  X
ROLL      aircraft roll angle flag             code         0       9                     X     X
TDAYSEC   ob. time in sec. since midnight UTC               0                             X     X


Single-level Observations
-------------------------

DATASRC   source that provided the data        code         0      10                     X    
PRFTYPE   profile type                         code         0      11                     X     X


MADIS ACARS-Profiles Variables - Character (all single-level)
-------------------------------------------------------------------------------------------
Code       Name                                Character               Notes      Database
                                               Size                              FSL  AWIPS
-------------------------------------------------------------------------------------------
STALOC    airport location                     51                       12        X
FLNUM     flight number                        13                                       X
TAILNUM   tail number                          12 (FSL) 9 (AWIPS)                 X     X


Notes
-----

1.  The ACARS profiles are data taken during aircraft taking off and
    landing at airports.  These data are organized into profiles associated 
    with the location of the airports.  Note that all of the data are also 
    available in the MADIS ACARS files, which also contains flight-level data.  
    Therefore users whose applications do not need the data organized into profiles 
    should use the ACARS files instead of the profiles.  The number of levels
    (up to 200) and the heights of those levels vary by station ("station" in the
    ACARS-profiles context is an airport).

2.  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.

3.  Air temperature is the temperature variable stored in the database.  For 
    aircraft that are also reporting moisture (a minority) 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 moisture 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.

4.  In the FSL database relative humidity is the moisture variable stored for
    TAMDAR data, and water vapor mixing ratio is used for non-TAMDAR data.
    Relative humidity is the form of moisture in the AWIPS database.  The 
    user can optionally select any of these variables, specific humidity, 
    dewpoint depression, or absolute humidity and these values will be 
    calculated by the MADIS API.  In all cases, the QC results from the 
    dewpoint temperature will be used (with the FSL database, there's currently 
    no QC in the AWIPS database).

5.  Reported water vapor QC codes -- FSL database:

       Value      Meaning
       -----      -------
        45        Missing data
        48        Normal operations, ground speed > 60 knots
        49        Normal operations, nonmeasurement mode,
                  ground speed < 60 knots
        50        Small RH, RH measured is < 1.5%; RH set to 1.5%
        51        Humidity element is wet. RH at 5.0 volts for < 120 seconds
        52        Humidity element contaminated.
                  RH at 5.0 volts for > 120 seconds
        53        Heater fail
        54        Heater fail and wet/contaminated humidity element
        55        Single validity bad.  One or more of the input parameters
                  for the mixing ratio calculation are invalid: TOT_PRESS,
                  MACH TAT_WVSS, or RH.  If RH is full scale, RH is
                  considered valid to allow wet/contaminated status to be
                  posted.
        56        Numeric error. Calculated mixing ratio at or above 100,
                  below 0.1-9, or negative, or absolute value of
                  denominator of calculations is less than 10-15.
        57        Dew point is greater than temperature

    Reported water vapor QC codes -- AWIPS database:

       Value      Meaning
       -----      -------
         0        Normal operations, measurement mode
         1        Normal operations, nonmeasurement mode
         2        Small RH
         3        Humidity element is wet
         4        Humidity element contaminated
         5        Heater fail
         6        Heater fail and wet/contaminated humidity element
         7        At least one of the input parameters used in the calculation
                  of mixing ratio is invalid
         8        Numeric error
         9        Sensor not installed
        63        Missing data

6.  The turbulence index is calculated from the median and maximum eddy 
    dissipation rates, as follows:

       Value      Meaning
       -----      -------
         0        median < 0.1 | maximum < 0.1
         1        median < 0.1 | 0.1 <= maximum < 0.2
         2        0.1 <= median < 0.2 | 0.1 <= maximum < 0.2
         3        median < 0.1 | 0.2 <= maximum < 0.3
         4        0.1 <= median < 0.2 | 0.2 <= maximum < 0.3
         5        0.2 <= median < 0.3 | 0.2 <= maximum < 0.3
         6        median < 0.1 | 0.3 <= maximum < 0.4
         7        0.1 <= median < 0.2 | 0.3 <= maximum < 0.4
         8        0.2 <= median < 0.3 | 0.3 <= maximum < 0.4
         9        0.3 <= median < 0.4 | 0.3 <= maximum < 0.4
        10        median < 0.1 | 0.4 <= maximum < 0.5
        11        0.1 <= median < 0.2 | 0.4 <= maximum < 0.5
        12        0.2 <= median < 0.3 | 0.4 <= maximum < 0.5
        13        0.3 <= median < 0.4 | 0.4 <= maximum < 0.5
        14        0.4 <= median < 0.5 | 0.4 <= maximum < 0.5
        15        median < 0.1 | 0.5 <= maximum
        16        0.1 <= median < 0.2 | 0.5 <= maximum
        17        0.2 <= median < 0.3 | 0.5 <= maximum
        18        0.3 <= median < 0.4 | 0.5 <= maximum
        19        0.4 <= median < 0.5 | 0.5 <= maximum
        20        0.5 <= median | 0.5 <= maximum
        63        Missing value

7.  The altitude-determining physical variable is pressure.  This is converted
    to altitude by using the U.S. Standard Atmosphere calculation.  The standard 
    atmosphere is used at all altitudes and under all pressure conditions.  Thus, 
    for instance, it is possible to have ACARS altitudes below ground level on 
    days with high atmospheric pressure.  (This is in contrast to other aviation 
    reports such as voice pireps that use a standard atmosphere to compute 
    altitude above 18,000 ft (MSL), but use the current altimeter setting for 
    lower altitudes).  The barometric-corrected height is used instead of a
    pressure altitude below approximately 18,000 ft in AMDAR reports from 
    Japanese airlines.

    The user can request either altitude or pressure, and the MADIS API will do 
    the conversion and return the requested variable.  In either case, the QC 
    results from the altitude variable will be applied.

8.  Icing condition:

       Value      Meaning
       -----      -------
         0        no ice is present
         1        ice is present

9.  Aircraft roll angle flag:

       Value      Meaning
       -----      -------
         0        good             
         1        bad              

10. Source that provided the data:

       Value      Meaning
       -----      -------
         0        ACARS (direct to FSL from airlines)
         1        MDCRS (from TG's BUFR file from ARINC)
         2        appeared in both ACARS and MDCRS data streams
         3        AMDAR data, including LH BUFR data
         4        TAMDAR data (from AirDat, LLC)
         5        Canadian AMDAR data from CMC
         6        European AMDAR data

11. Profile type:

       Value      Meaning
       -----      -------
        -1        Descending
         1        Ascending

    Note that the profiles are always ordered by ascending height.  The 
    profile type indicates whether the data were taken on landing or 
    takeoff.

12. The airport code, latitude and longitude are available in both
    the FSL and AWIPS databases.  The FSL database also includes the
    location, elevation, and WMO ID of the airport.

13. The RH1, RH2, RHUNCER, TDUNCER and GPSHT variables are only available 
    for TAMDAR reports.  For more information on TAMDAR see 
    http://www.crh.noaa.gov/tamdar.

14. The TAMDAR reports include two sensors used for relative humidity.  A
    "consensus RH" is also reported as the primary moisture variable, and
    this is what's used for RH, TD, etc.  Users interested in seeing the
    values from both sensors can select the RH1 and RH2 variables.

    The RH uncertainty variable is the theoretical RSS (root-summed-squared) 
    uncertainty of the consensus RH value in percent.  Two error source 
    components are used in the RSS calculation:  temperature uncertainty 
    (assumed to be +/- 0.4C) and the RH sensor uncertainty (assumed to be 
    +/- 2% absolute error [not RH times 2%]).  Other inputs to the calculation 
    are air temperature, pressure altitude and indicated air speed.  The
    uncertainty is additive with the reported humidity, so if RH is 30% and 
    RHUNCER is 20%, the estimated range of the RH is 30% +-20%, i.e., 10-50%.

    Dewpoint uncertainty is derived from the RH uncertanty variable in the 
    following way.  If the RH uncertainty is >= 0.49, the dewpoint uncertainty 
    is set to 999.  Otherwise, two subsidiary dewpoints are calculated by 
    assuming the RH is 1) RH + RHUNCER, and, 2) RH - RHUNCER.  The dewpoint 
    uncertainty is one-half the difference between 1) and 2).

15. The MEDEDR, MAXEDR, TURBIDX and ICECOND variables for TAMDAR reports
    are accompanied by level 1 QC results from the TAMDAR provider.  These 
    variables can also be reported by the other providers, but these do not 
    have any QC.  Therefore, API users interested in seeing the data from
    these providers should request all data, not just data passing any
    QC level.

16. The eddy dissipation rates available in the ACARS and TAMDAR reports 
    are calculated using different algorithms.  The NCAR algorithm used 
    for ACARS calculates EDR from fluctuations in the vertical motion of 
    the aircraft (current algorithm), or fluctuations in the vertical 
    wind (proposed new algorithm).  The TAMDAR algorithm calculates EDR 
    from fluctuations in the horizontal wind, as revealed by fluctuations 
    in the indicated airspeed.  When the turbulence is isotropic, the NCAR 
    and TAMDAR algorithms should agree.  

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