Worldwide Radiosonde Launch Sites Notes

MJ Mahoney
Last Revision: June 19, 2008

Since radiosondes play a key role in MTP data analysis, it is important to have a comprehensive list of launch sites worldwide, so that appropriate soundings can be downloaded wherever and whenever a field campaign occurs. Initially we used WMO Publication No. 9 Volume A - Observing Stations -- called a flatfile -- since it is the most authorative source. Documentation on the format of these more than 11,600 surface and upper-air stations can be found here. A subroutine named UAfromFlatfile was written more than a decade ago to read this flatfile and extract relevant information such as launch site WMO station number, latitude, longitude and geopotential height. However, the WMO flatfile did not provide the ICAO name for a site (if there was one).

Since it is easier to remember ICAO names than it is to remember WMO (station) numbers, I stopped using the WMO flatfile and migrated to using a GEMPAK listing of radiosonde launch sites, which does include both the ICAO name and WMO number. When I started this many years ago, you could download a file named station-query.html which contained all the launch sites worldwide. UAfromFlatfile was modified to convert the sites in station-query.html into binary records in a file named UA_MTP.BIN with the following data structure found in the RAOBcommon.BAS module:

'GEMPAK Station List
'http://www.unidata.ucar.edu/software/gempak/tutorial/station_tables.html
'Station tables should use the following format:
'(A8,1X,I6,1X,A32,1X,A2,1X,A2,1X,I5,1X,I6,1X,I5)
' ^     ^     ^      ^     ^     ^     ^     ^
' |     |     |      |     |     |     |     |
' |     |     |      |     |     |     |     --- Elevation (meters)
' |     |     |      |     |     |     --- Longitude (west = negative)
' |     |     |      |     |     --- Latitude (south = negative)
' |     |     |      |     --- Country
' |     |     |      --- State
' |     |     --- Station Name
' |     --- Station Number
' --- Station ID
'Note that Latitude and Longitude are expressed in hundredths of decimal degrees (not DMS!).
'0        1         2         3         4         5         6         7
'1234567890123456789012345678901234567890123456789012345678901234567890123
'$$$$$$$$ %%%%%% $$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$ $$ $$ %%%%% %%%%%% %%%%%
'VBCI      48109 COCO ISLAND                      -- BM  1412   9337     3
'VBG       72393 VANDENBERG AFB                   CA US  3465 -12057   112

Type GPrecord
  GPcards As Long               ' CARDS number = WMO*10
  GPicao As String * 8          ' Alpha name
  GPlatitude As Single          '
  GPlongitude As Single         '
  GPaltitude As Integer         ' meters MSL
  GPregion As Integer           ' WMO region
  GPcountry As String * 2       ' FIPS PUB 10-4 Country Code
  GPstate As String * 2         '
  GPstation As String * 32      '
  GPspare As Integer            ' Spare
End Type
Unfortunately, the complete station-query.html file does not seem to be available. To overcome this short-coming, there where options on the RAOBsites form (under the RAOBman Export tab) that allowed sites to be added, removed, or editted in MTP_UA.BIN.

I decided to see if I could find a some other current source of worldwide launch sites, and was successful. The NOAA Earth System Research Laboratory (ESRL) Global Systems Division (GSD, formerly FSL) does provide current radiosonde launch site documentation because (in their own words):

The station history is an integral part of the radiosonde archive.  Information contained in the station history are required for output of data.  As a result, a sounding will not be output unless a corresponding entry exists in the station history file.  We strive to maintain an updated station history tracking changes of location, station identifiers and dates station moves as they occur.  You are encouraged to update your copy of this station history frequently.  Additionally, we value your feedback on possible corrections to this file when a station moves or our information is incorrect.

This is exactly what is needed! So the Add, Remove, and Edit buttons were removed from the RAOBsites form shown in Figure 1.

frmRAOBsites.png
Figure 1. The RAOBsites form.

The procedure now for updating the MTP_UA.BIN file is as follows:

1) Go to the NOAA ESRL GSD Station History documentation and download the intl2000.wmo text file file to the C:/MTP/RAOB/BIN/ folder (or just right click on the last link and select the Save Link As menu option).

2) Run the CRLF.exe program to add a carriage return to each line of the intl2000.wmo file.

3) Select the Export tab in the RAOBman.exe program, and then depress the Show RAOB Details button near the bottom of the form bring up the RAOBsites form shown in Figure 1.

4) Finally, depress the Gen BIN button on the buttom left of the RAOBsites form to create a new version of the C:\MTP\RAOB\BIN\MTP_UA.BIN file. This is the only RAOB file now read by MTP data analysis programs that need radiosonde location information.

More documenation on the RAOBsites form is available here.