SGP/SONDE/C1 - Surface pressure incorrect

I think the operator inadvdertently typed an 89 instead of a 78 when entering the surface 
pressure value.  The value entered is 989.9 hPa but the value shown in the raw data file 
at launch is 978.9.  As a result, the absolute altitudes in this sounding will be 
slightly incorrect as will be the ascent rate during the first 30 seconds of flight.

• Ascent Rate(asc)
• altitude above sea levelaltunits(alt)

SGP/SONDE/C1 - Surface pressure incorrect

I think the operator inadvdertently mistyped a digit when entering the surface pressure 
value.  The value entered is 975.6 hPa but the value shown in the raw data file at launch 
is 972.6.  As a result, the absolute altitudes in this sounding will be slightly incorrect 
as will be the ascent rate during the first 30 seconds of flight.

• Ascent Rate(asc)
• altitude above sea levelaltunits(alt)

SGP/SONDE/C1 - Bad RH Data

The RH values below 6 km are incorrect.  The problem relates to a failure of the GC25 
ground check set used before this particular sounding.  The failure seems to have affected 
the sensor calibration with the effect that one of the two sensors was reading artificially 
high.  Because the internal processing software uses the highest of the two sensor 
readings, the bad sensor value is chosen whenever it is not heated.

• Surface dew point temperature(dp)
• Relative humidity scaled, by total column amount from MWR(rh)

SGP/SONDE/C1 - Bad T/RH and surface P.

Apparently multiple failures.  The radiosonde temperature sensor broke on launch causing 
an approximate 35 degC negative offset and as a result, the RH is incorrect.  Furthermore, 
it appears that the pressure sensor was off by approximately 4 hPa, though this would 
not affect the altitude calculation, the absolute pressure is wrong.

• Dry-Bulb Temperature(tdry)
• Relative humidity scaled, by total column amount from MWR(rh)
• pressure at constant pressure surface(pres)

SGP/SONDE/C1 - Temperature/RH incorrect

The temperature throughout this sounding is too high and as a result the RH values will be 
incorrect as well.  I'm not sure what is wrong here but the operators noted reasonable 
values (18.1 degC, 87%) in the log before launch.  Review of the raw data, however, shows 
the sonde reporting temperatures nearly 20 degC higher.  I suppose it is possible that 
the operator entered into the log the reference temperature from the GC25 ground check set 
rather than the temperature reported by the sonde - I can't think of any other 
explanation - there is no doubt that the temperature sensor on this sonde was bad.

• Surface dew point temperature(dp)
• Dry-Bulb Temperature(tdry)
• Relative humidity scaled, by total column amount from MWR(rh)

• Relative humidity scaled, by total column amount from MWR(rh)
• Dry-Bulb Temperature(tdry)

SGP/SONDE/C1 - Increased precision for alt, dp, pres, rh, tdry

The output precision of the following variables was increased 20060928

alt  changed from 1m to 0.1m
dp   changed from 0.1degC to 0.01degC
pres changed from 0.1 hPa to 0.01 hPa
RH   changed from 1%RH to 0.01%RH
tdry changed from .1degC to 0.01degC

Note that the increase in precision does not necessarily imply an increase in accuracy.  
Users are cautioned to continue to use their best scientific judgement when using these or 
any other data.

• Surface dew point temperature(dp)
• Dry-Bulb Temperature(tdry)
• Relative humidity scaled, by total column amount from MWR(rh)
• pressure at constant pressure surface(pres)
• altitude above sea levelaltunits(alt)