SALLJEX: Upper Air Cordoba Sounding Data (JOSS)
1.0 General Description
This dataset consists of 67 soundings released from Cordoba,
Argentina during The South American Low-Level Jet Experiment (SALLJEX),
a component of the CLIVAR/VAMOS program. Rawinsondes were typically
released at least once (12 UTC) per day. This dataset contains profiles
for 06 December 2002 thru 14 February 2003. Vaisala rawinsondes employing
GPS wind finding were utilized at Cordoba during SALLJEX.
The sonde data were quality controlled at the Joint Office for Science
Support (JOSS) at NCAR, using methods similar to those used to quality
control the TOGA COARE sounding data (Loehrer et al., 1996; their
sections 3a-e). See section 5.0 for more details on JOSS quality control
procedures for the Cordoba Sounding Data
2.0 Parameters in Raw Dataset
Parameters Units
--------------------------------------
Time Seconds
Pressure Millibars
Temperature Deg C
Dew Point Deg C
Relative Humidity %
U wind component m/s
V wind component m/s
Wind Speed m/s
Wind Direction Deg
Ascension Rate m/s
Longitude Deg
Latitude Deg
Range km
Azimuth Angle Deg
Altitude Geopotential Meters
Pressure Quality Code mb
Temp Quality Code Deg C
Humidity Quality Code Deg C
U comp Quality Code m/s
V comp Quality Code m/s
UV Quality Code m/s
--------------------------------------
3.0 Conversion to JOSS CLASS format (ASCII text)
3.1 The raw vertical resolution time, temperature,
relative humidity, altitude, pressure, dew point,
wind direction, and wind speed were kept without change.
3.2 The ascension rate was calculated for each data point
(excluding the surface, where it was given a missing
value) based on the altitude and time at two levels,
the current time level and the previous time level. If the
data point for which the ascension rate was being calculated
had missing time or altitude, the ascension rate was not
calculated at that level and was flagged as missing. If the
data point prior to that for which the ascension rate was
being calculated had a missing time or altitude, then the
data point two data points prior to the present one was
used, and so on until one with non-missing time and altitude
was found. If there are no non-missing previous data points
the ascension rate is set to missing.
3.3 Due to CLASS format constraints, Dew Points less than
-99.9 Deg C were given a value of -99.9 Deg C and were
flagged as being questionable.
4.0 JOSS CLASS Format (ASCII text) Description
4.1 Header records
The header records (15 total records) contain data type, project
ID, site ID, site location, actual release time, nominal release
time, and possibly other specialized information. The first five
header lines contain information identifying the sounding, and
have a rigidly defined form. The following 6 header lines are
used for auxiliary information and comments about the sounding,
and they vary significantly from dataset to dataset (For Cordoba
these lines contain information on the radiosonde and other
information). This is the last time the dataset was released. It
has the format yyyymmddhh). The next line (line 12) contains the
Nominal date and time of the release. The last 3 header records
contain header information for the data columns. Line 13 holds the
field names, line 14 the field units, and line 15 contains dashes
('-' characters) delineating the extent of the field.
The six standard header lines are as follows:
Line Label (fixed to 35 char in length) Contents
1 Data Type: Description of type and
resolution of data.
2 Project ID: ID of weather project.
3 Release Site Type/Site ID: Description of release
site.
4 Release Location (lon,lat,alt): Position of release site,
in format described
below.
5 UTC Release Time: Time of release, in
format:
yyyy, mm, dd, hh:mm:ss
12 UTC Nominal Release Time: Nominal release time.
The release location is given as: lon (deg min), lat (deg min),
lon (dec. deg), lat (dec. deg), alt (m)
Longitude in deg min is in the format: ddd mm.mm'W where ddd is
the number of degrees from True North (with leading zeros if
necessary), mm.mm is the decimal number of minutes, and W
represents W or E for west or east longitude, respectively.
Latitude has the same format as longitude, except there are only
two digits for degrees and N or S for north/south latitude. The
decimal equivalent of longitude and latitude and station
elevation follow.
The six non-standard header lines may contain any label and
contents. The label is fixed to 35 characters to match the
standard header lines.
Sample header records are provided in the sample data file in
section 4.3.
4.2 Data records
The data records each contain time from release, pressure,
temperature, dew point, relative humidity, U and V wind
components, wind speed and direction, ascent rate, balloon
position data, altitude, and quality control flags (see QC code
description). Each data line contains 21 fields, separated by
spaces, with a total width of 130 characters. The data are
right-justified within the fields. All fields have one decimal
place of precision, with the exception of latitude and longitude,
which have three decimal places of precision. The contents and
sizes of the 21 fields that appear in each data record are as
follows:
Field Format Missing
No. Width Parameter Units Value
----------------------------------------------------------------------
1 6 F6.1 Time Seconds 9999.0
2 6 F6.1 Pressure Millibars 9999.0
3 5 F5.1 Dry-bulb Temperature Degrees C 999.0
4 5 F5.1 Dew Point Temperature Degrees C 999.0
5 5 F5.1 Relative Humidity Percent 999.0
6 6 F6.1 U Wind Component Meters/Second 9999.0
7 6 F6.1 V Wind Component Meters/Second 9999.0
8 5 F5.1 Wind Speed Meters/Second 999.0
9 5 F5.1 Wind Direction Degrees 999.0
10 5 F5.1 Ascension Rate Meters/Second 999.0
11 8 F8.3 Longitude Degrees 9999.0
12 7 F7.3 Latitude Degrees 999.0
13 5 F5.1 Variable (see below) 999.0
14 5 F5.1 Variable (see below) 999.0
15 7 F7.1 Altitude Meters 99999.0
16 4 F4.1 QC flag for Pressure Code (see below) 99.0
17 4 F4.1 QC flag for Temperature Code (see below) 99.0
18 4 F4.1 QC flag for Humidity Code (see below) 99.0
19 4 F4.1 QC flag for U Component Code (see below) 99.0
20 4 F4.1 QC flag for V Component Code (see below) 99.0
21 4 F4.1 QC flag for Ascension Rate Code (see below) 99.0
----------------------------------------------------------------------
Fields 13 and 14 are `variable' because depending on the sounding
system the variables used in these positions can vary. For the
Cordoba soundings, these fields have been set to missing.
Fields 16 through 21 contain the Quality Control information
(flags) generated locally at JOSS. These flags are based on the
automated checks. See Sections 5.0 for further information.
The JOSS QC flags are as follows:
Code Description
----------------------------------------------------------------------
99.0 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')
----------------------------------------------------------------------
4.3 Sample data
The following is a sample portion of a JOSS CLASS format file
including header records. The data portion is much longer than
80 characters and, therefore, wraps around to a second line.
Data Type: High Resolution Sounding
Project ID: SALLJEX
Release Site Type/Site ID: Cordoba,Argentina CBA
Release Location (lon,lat,alt): 64 12.60'W, 31 19.20'S, -64.210, -31.320,
474.0
UTC Release Time (y,m,d,h,m,s): 2003, 01, 01, 11:15:00
Radiosonde Manufacturer: Vaisala
Radiosonde Serial Number: 242612305
Sonde Type/ID/Sensor ID/Tx Freq: PTU GPS
/
/
/
Nominal Release Time (y,m,d,h,m,s):2003, 01, 01, 12:00:00
Time Press Temp Dewpt RH Ucmp Vcmp spd dir Wcmp Lon Lat
Ele Azim Alt Qp Qt Qrh Qu Qv QdZ
sec mb C C % m/s m/s m/s deg m/s deg deg
deg deg m code code code code code code
------ ------ ----- ----- ----- ------ ------ ----- ----- ----- -------- ------
- ----- ----- ------- ---- ---- ---- ---- ---- ----
0.0 960.6 17.8 16.5 92.0 1.0 0.0 1.0 270.0 999.0 -64.210 -31.320
999.0 999.0 474.0 3.0 3.0 3.0 99.0 99.0 9.0
2.0 959.8 17.5 15.1 86.0 0.8 0.1 0.8 266.0 4.0 -64.210 -31.320
999.0 999.0 482.0 3.0 3.0 3.0 99.0 99.0 99.0
4.0 958.6 17.5 15.1 86.0 0.8 0.1 0.8 265.0 5.5 -64.210 -31.320
999.0 999.0 493.0 99.0 99.0 99.0 99.0 99.0 99.0
6.0 957.7 17.4 15.2 87.0 0.8 0.1 0.8 263.0 4.0 -64.210 -31.320
999.0 999.0 501.0 99.0 99.0 99.0 99.0 99.0 99.0
8.0 956.7 17.4 15.2 87.0 0.7 0.1 0.7 262.0 4.5 -64.210 -31.320
999.0 999.0 510.0 99.0 99.0 99.0 99.0 99.0 99.0
5.0 Quality Control Procedures
This dataset underwent the JOSS QC process which consisted of
internal consistency checks. The internal consistency checks included
gross limit checks on all parameters and vertical consistency checks
on temperature, pressure, and ascension rate.
5.1 Automated Quality Control Procedures
5.1.1 Gross Limit Checks
These checks were conducted on each sounding and data were
automatically flagged as appropriate. Only the data point
under examination was flagged. JOSS conducted the
following gross limit checks on the Cordoba
Sounding Data. In the table P = pressure, T = temperature,
RH = relative humidity, U = U wind component, V = V wind
component, B = bad, and Q = questionable.
----------------------------------------------------------------
Parameter(s) Flag
Parameter Gross Limit Check Flagged Applied
----------------------------------------------------------------
Pressure < 0 mb or > 1030 mb P B
Altitude < 0 m or > 40000 m P, T, RH Q
Temperature < -99.9C or > 40C T Q
Dew Point < -99.9C or > 30C RH Q
> Temperature T, RH Q
Relative Humidity < 0% or > 100% RH B
Wind Speed < 0 m/s or > 100 m/s U, V Q
> 150 m/s U, V B
U Wind Component < 0 m/s or > 70 m/s U Q
> 150 m/s U B
V Wind Component < 0 m/s or > 70 m/s V Q
> 150 m/s V B
Wind Direction < 0 deg or > 360 deg U, V B
Ascent Rate < -10 m/s or > 10 m/s P, T, RH Q
----------------------------------------------------------------
5.1.2 Vertical Consistency Checks
These checks were conducted on each sounding and data were
automatically flagged as appropriate. These checks were
started at the lowest level of the sounding and compared
neighboring values. In the case of checks ensuring that
the values increased/decreased as expected, only the data
point under examination was flagged. However, for the
other checks, all of the data points used in the
examination were flagged. All items within the table are
as previously defined.
----------------------------------------------------------------
Vertical Consistency Parameter(s) Flag
Parameter Check Flagged Applied
----------------------------------------------------------------
Time decreasing/equal None None
Altitude decreasing/equal P, T, RH Q
Pressure increasing/equal P, T, RH Q
> 1 mb/s or < -1 mb/s P, T, RH Q
> 2 mb/s or < -2 mb/s P, T, RH B
Temperature < -15 C/km P, T, RH Q
< -30 C/km P, T, RH B
from surface to 150 mb:
> 15 C/km (not applied
at p < 150mb) P, T, RH Q
> 30 C/km (not applied
at p < 150mb) P, T, RH B
for pressures < 150 mb:
> 100 C/km (not applied
at p > 150mb) P, T, RH Q
> 10000 C/km (not applied
at p > 150mb) P, T, RH B
Ascent Rate change of > 3 m/s
or < -3 m/s P Q
change of > 5 m/s
or < -5 m/s P B
----------------------------------------------------------------
6.0 References
Loehrer, S. M., T. A. Edmands and J. A. Moore, 1996: "TOGA COARE
upper-air sounding data archive: development and quality control
procedures", BAMS, 77, 2651-2671.
Questions about the data should be directed to:
José Meitín
UCAR/JOSS
P.O. Box 3000
Boulder, CO. 80307-3000
voice: 303 497-8168
fax: 303 497-8158
meitin@ucar.edu