ExampleSonde           package:RadioSonde           R Documentation

_E_x_a_m_p_l_e _S_o_n_d_e/_B_a_l_l_o_o_n/_P_r_o_f_i_l_e_r _D_a_t_a

_D_e_s_c_r_i_p_t_i_o_n:

     This data was collected by a radiosonde which was carried aloft by
     a  weather balloon. This data was collected as part of a special
     field program, but the instrument and data formats are very common
      in the atmospheric community.

     Fundamentally; temperature, pressure, and humidity sensors are
     bundled  with a radio transmitter and are either sent aloft on a
     balloon  (rawindsonde) or tied to a small parachute and dropped
     from a plane  (dropsonde). Either way, the location of the sonde
     is observed  (either visually or with GPS), the data from the
     radio transmitter  recorded, and the result is an ascii file that
     contains a header  (of varying length) with descriptive
     information followed by a  table of information.

     For rawindsondes, the first entry for the table is actually the 
     surface data from the weather station, but the remaining entries 
     are from the sonde. Also, the wind is inferred from the position 
     of the balloon. Since this is real data, there are missing values
     - which arise all the time. If you get a profile without missing
     values, you can be sure it is synthetic or interpolated. The
     datastreme ends when the operator calls it quits. This happens
     when a) the balloon breaks, or b) the radio reception has so many
     dropouts that is is not worth it anymore. Different fields have
     different `missing' flags. Where possible, we replace the
     "standard" missing flags with  `NaN'

_U_s_a_g_e:

     data(ExampleSonde)

_F_o_r_m_a_t:

     `ExampleSonde' is the nominal output and is a mixture of ancillary
     data (contained in the first ???? lines of the file), and the
     instrument  measures and some derived fields that follow in a
     fixed-format table with an unknown number of lines.

       Field  varname  width  format  description                 units             missing value
       [ 1]   time     6      F6.1    Time                        Seconds           9999.0
       [ 2]   press    6      F6.1    Pressure                    Millibars         9999.0
       [ 3]   temp     5      F5.1    Dry-bulb Temperature        Degrees C         999.0
       [ 4]   dewpt    5      F5.1    Dew Point Temperature       Degrees C         999.0
       [ 5]   rhum     5      F5.1    Relative Humidity           Percent           999.0
       [ 6]   uwind    6      F6.1    U Wind Component            Meters/Second     9999.0
       [ 7]   vwind    6      F6.1    V Wind Component            Meters/Second     9999.0
       [ 8]   wspd     5      F5.1    Wind Speed                  Meters/Second     999.0
       [ 9]   wdir     5      F5.1    Wind Direction              Degrees           999.0
       [10]   dz       5      F5.1    Ascension Rate              Meters/Second     999.0
       [11]   lon      8      F8.3    Longitude                   Degrees           9999.0
       [12]   lat      7      F7.3    Latitude                    Degrees           999.0
       [13]   range    5      F5.1    Variable (see below)                          999.0
       [14]   angle    5      F5.1    Variable (see below)                          999.0
       [15]   alt      7      F7.1    Altitude                    Meters            99999.0
       [16]   qp       4      F4.1    QC flag for Pressure        Code (see below)  99.0
       [17]   qt       4      F4.1    QC flag for Temperature     Code (see below)  99.0
       [18]   qh       4      F4.1    QC flag for Humidity        Code (see below)  99.0
       [19]   qu       4      F4.1    QC flag for U Component     Code (see below)  99.0
       [20]   qv       4      F4.1    QC flag for V Component     Code (see below)  99.0
       [21]   quv      4      F4.1    QC flag for Ascension Rate  Code (see below)  99.0

     The `missing value' flags are in brackets []. Fields 13 and 14 are
     `variable' because depending on the sounding system the variables
     used in these positions can vary.

     Fields 16 through 21 contain the Quality Control information
     (flags)  generated at JOSS. These flags are based on the automated
     or  visual checks made.

     The JOSS QC flag codes are as follows:

_9_9._0 Unchecked (QC information is `missing.')  (`UNCHECKED')

_1._0 Checked, datum seems physically reasonable.  (`GOOD')

_2._0 Checked, datum seems questionable on physical basis.  (`MAYBE')

_3._0 Checked, datum seems to be in error.  (`BAD')

_4._0 Checked, datum is interpolated.  (`ESTIMATED')

_9._0 Checked, datum was missing in original file.  (`MISSING')

_S_o_u_r_c_e:

     <URL: http://www.joss.ucar.edu/cgi-bin/codiac/dss?2.151>

_S_e_e _A_l_s_o:

     `getsonde', `plotsonde', `skewt.lines', `skewt.points'

_E_x_a_m_p_l_e_s:

     filename <- system.file("exampleData", "ExampleSonde.txt", package = "RadioSonde")   
     sample.sonde <- getsonde(filename)

