PYE/MWRP/M1 - Bias in Ground Relative Humidity Measurement

On June 17 2005, the MWRP was re-installed at PYE after the Super Blower was replaced by 
the old style dew blower. The relative humidity ground sensor in the dew blower is not as 
accurate. This resulted in a negative relative humidity bias of about 5.9 %. In other 
words the MWRP sensor was underestimating the relative humidity. The bias was determined by 
comparing MWRP measurements with SMET and radiosonde measurements. The MP.cfg file for 
the MWRP was changed to reflect this bias on 09/02/2005 and will take effect on 09/03/2005 
0000 GMT

• Surface water vapor density at instrument(surfaceWaterVaporDensity)
• Surface relative humidity at instrument(surfaceRelativeHumidity)

• Raw data stream - documentation not supported(raw)

PYE/MWR/M1 - New software version (4.15) installed

A problem began with the installation of MWR.EXE version 4.12 in July 2002. The software 
had been upgraded from a "DOS" to a "Windows"-compiled program to address an earlier 
problem.  The software upgrade corrected the earlier problem but introduced a new one that 
caused line-of-sight observing cycles to be skipped, a 15% reduction in the number of tip 
curves, and saturation of CPU usage. Software versions 4.13 and 4.14 also produced these 
problems.

The new MWR software, version 4.15, was installed on 9/13/2005. As a consequence of this 
upgrade, the tip curve frequency increased. The tip cycle time decreased from ~60s to ~50s.

• 23.8 GHz sky brightness temperature derived from tip curve(tbsky23tip)
• Noise injection temp at 23.8 GHz derived from this tip(tnd23I)
• 31.4 GHz sky signal(tipsky31)
• Noise injection temp at nominal temperature at 31.4 GHz(tnd_nom31)
• Blackbody kinetic temperature(tkbb)
• Ambient temperature(tkair)
• Noise diode mount temperature(tknd)
• 31.4 GHz Blackbody signal(bb31)
• Total liquid water along zenith path using tip-derived brightness temperatures(liqtip)
• 23.8 GHz Blackbody signal(bb23)
• 23.8 GHz blackbody+noise injection signal(bbn23)
• 31.4 GHz sky brightness temperature derived from tip curve(tbsky31tip)
• 23.8 GHz sky signal(tipsky23)
• 23.8 GHz goodness-of-fit coefficient(r23)
• Temperature correction coefficient at 31.4 GHz(tc31)
• Noise injection temp at 31.4 GHz derived from this tip(tnd31I)
• Total water vapor along zenith path using tip-derived brightness temperatures(vaptip)
• Noise injection temp at 23.8 GHz adjusted to tkbb(tnd23)
• Mixer kinetic (physical) temperature(tkxc)
• Noise injection temp at nominal temperature at 23.8 GHz(tnd_nom23)
• 31.4 GHz goodness-of-fit coefficient(r31)
• Noise injection temp at 31.4 GHz adjusted to tkbb(tnd31)
• Temperature correction coefficient at 23.8 GHz(tc23)
• 31.4 GHz blackbody+noise injection signal(bbn31)

• Noise injection temp at nominal temperature at 23.8 GHz(tnd_nom23)
• 31.4 GHz blackbody+noise injection signal(bbn31)
• Temperature correction coefficient at 23.8 GHz(tc23)
• Noise injection temp at 31.4 GHz adjusted to tkbb(tnd31)
• Mean total liquid water amount along LOS path(liq)
• Mixer kinetic (physical) temperature(tkxc)
• Noise injection temp at 23.8 GHz adjusted to tkbb(tnd23)
• 31.4 GHz Blackbody signal(bb31)
• Mean 23.8 GHz sky brightness temperature(tbsky23)
• 31.4 GHz sky signal(sky31)
• 23.8 GHz sky signal(sky23)
• Ambient temperature(tkair)
• 23.8 GHz Blackbody signal(bb23)
• 23.8 GHz blackbody+noise injection signal(bbn23)
• Noise diode mount temperature(tknd)
• Mean 31.4 GHz sky brightness temperature(tbsky31)
• Temperature correction coefficient at 31.4 GHz(tc31)
• Sky/Cloud Infra-Red Temperature(sky_ir_temp)
• Blackbody kinetic temperature(tkbb)
• Noise injection temp at nominal temperature at 31.4 GHz(tnd_nom31)
• Mean total water vapor amount along LOS path(vap)

PYE/GNDRAD/M1 - Reprocess: Longwave Calibration error

Modified pyrgeometer calibration procedures were implemented beginning in December 2003.  
These modified procedures introduced a calibration bias in the longwave data.  The 
previous procedures were re-implemented at all sites between December 2005 and February 2006 to 
restore proper calibrations.                                                             
                The data collected while the incorrect procedures were in place are 
being reprocessing to remove the calibration bias.  Note, this also affected standard 
deviation, maximum and minimum data fields.

• Upwelling (10 meter) Longwave Hemispheric Irradiance, Ventilated Pyrgeometer(up_long_hemisp)