TWP/SKYRAD/C3 - Incorrect NIP cal coefficient

During our site visit comparison at Darwin we observed that the skyrad NIP was reading 
about 50 w/m2 lower than the comparison cavity radfiometer and the replacement NIP on the 
comparison stand. We found that the calibration coefficient for the NIP (responsivity at 
45o)was put in as 8.64X10-6. The NIP was new and had not been calibrated at SGP. The 
factory number was 8.04X10-6. We corrected the calibration coefficient and the instruments 
agreed to better than 5 w/m2.

• Shortwave Direct Normal Irradiance, Pyrgeometer, Minima(short_direct_normal_min)
• Shortwave Direct Normal Irradiance, Pyrgeometer(short_direct_normal)
• Shortwave Direct Normal Irradiance, Pyrgeometer, Maxima(short_direct_normal_max)
• Shortwave Direct Normal Irradiance, Pyrgeometer, Standard Deviation(short_direct_normal_std)

TWP/SKYRAD/C3 - Reprocess: NIP calibrations incorrect

On 05/20 during installtion of the new Campbell datalogger system and associated program 
the NIP (S/N 33551E6) was assigned an incorrect calibration coefficient.  A coefficient of 
116.01 W/m2/mV was applied when it should have been 124.378 W/m2/mV.
TWP reports SV0405D and SV0409D detail the activities which lead to this DQR.

• Raw data stream - documentation not supported(Raw data stream - documentation not supported)

• Shortwave Direct Normal Irradiance, Pyrgeometer, Minima(short_direct_normal_min)
• Shortwave Direct Normal Irradiance, Pyrgeometer(short_direct_normal)
• Shortwave Direct Normal Irradiance, Pyrgeometer, Maxima(short_direct_normal_max)
• Shortwave Direct Normal Irradiance, Pyrgeometer, Standard Deviation(short_direct_normal_std)

TWP/GNDRAD/C3 - IRT bias

The IRT measured higher surface temperatures than expected from the PIR, even at night.

• Surface Infra-Red Temperature Minima(sfc_ir_temp_min)
• Effective Surface (Skin) Temperature(sfc_ir_temp)
• Surface Infra-Red Temperature Maxima(sfc_ir_temp_max)

TWP/SKYRAD/C3 - IRT damaged

The analog output of the IRT was damaged by a lightning strike. The problem was corrected 
by replacing the instrument with a spare. The damaged IRT was returned to the vendor for 
repair.

• Sky Infra Red Temperature Minima(sky_ir_temp_min)
• Sky Infra-Red Temperature(sky_ir_temp)
• Standard Deviation of Sky Infra Red Temperature(sky_ir_temp_std)

• Instantaneous Sky/Cloud Infrared(inst_sky_ir_signal)

TWP/GNDRAD/C3 - IRT power

The IRT failed to report after a planned power outage to add lightning protection modules 
to the AC power wiring. The problem was corrected when a loose power connection to the 
logger was found, rectified, and power restored to the logger.

• Surface Infra-Red Temperature, Standard Deviation(sfc_ir_temp_std)
• Surface Infra-Red Temperature Minima(sfc_ir_temp_min)
• Effective Surface (Skin) Temperature(sfc_ir_temp)
• Surface Infra-Red Temperature Maxima(sfc_ir_temp_max)

TWP/SMET/C3 - ORG data noisy due to degraded ground

SMET Rain Data began to be noisy during December 2005 and the problem slowly became worse 
over time so that in February 2006 the ORG was reporting with a constant background value 
of around 0.10 mm/hr rain rate.  ORG voltage showed a near constant value above the 85mV 
threshold.  The ground for the ORG had become degraded and was lost due to corrosion.

• Precipitation mean(precip_mean)
• Precipitation maximum(precip_max)
• Precipitation standard deviation(precip_sd)
• precipitation minimum(precip_min)

TWP/GNDRAD/C3 - 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, Pyrgeometer(up_long_hemisp)

TWP/SMET/C3 - Reprocess: Barometric Data Changed from hPa to kPa

Barometric pressure data was converted from hPa to kPa in order to standardize the 
measurement units among ARM sites and to conform to accepted standard units determined by the 
scientific community.

• Barometric Pressure(atmos_pressure)

TWP/SMET/C3 - Reprocess: Tipping bucket rain gauge added

A tipping bucket rain gauge was added to the SMET suite of instruments effective 20060926. 
 Two new variables (count and rain amount) were added at the end of the twpsmet60sC1.b1 
datastream.  When reprocessing of this datastream occurs these variables will be added 
with -9999 (missing) as the value for dates prior to gauge installation.

• base time(base_time)