| Description: | The pressure values and hence altitude values are most likely incorrect
in this sounding. It also appears that an incorrect surface pressure
value was entered by the operator. The surface pressure value in
the data (986.8) is somewhat higher than the surface pressures for the
neighboring soundings and higher than recorded in the raw data collected
before launch (~978 hPa). The first pressure value recorded by the
sonde after launch is 884.8 hPa. Analysis of the absolutely raw data
reveals that the sonde was reading about 978 hPa well before launch,
then suddenly dropped to 886.8 at which it remained stable for several
minutes, then began slowly decreasing as would be expected after launch.
My best guess is that the sonde was somehow damaged during handling
before launch resulting in erroneous pressure values. Relative pressure
changes from an 'apparent' surface value of 886.8 hPa may be correct,
but the absolute pressure values are not. |