SGP/SIRS/E11 - Reprocess: Incorrect shortwave radiometer calibration coefficients

During the pyrgeometer instrument (PIR) changeout a datalogger program was loaded with 
incorrect calibration coefficients for the shortwave instruments.  The affected measurements 
(instruments) were: downwelling diffuse (8-48), upwelling shortwave (PSP), direct normal 
(NIP) and downwelling shortwave (PSP)

Field tech reports the datalogger program was corrected on 4/27/04.  Archive data review 
shows this was not the case and the corrected datalogger program was uploaded sometime 
late day 5/4/04. The end date for this DQR was chosen to be 5/5/04 0000 the first full day 
of the correct datalogger program.

Recalculate irradiances by determining original mV signal and reapplying the correct 
calibration coefficients.  For each one minute irradiance value perform the following 
calculations by instrument:
DD(corrected) = (DD/107.24)*123.27
US(corrected) = (US/113.19)*127.75
NIP(corrected)= (NIP/120.17)*126.69
DS(corrected) = (DS/118.46)*126.56

• Raw data stream - documentation not supported

• up_short_hemisp_std
• Radiation, shortwave, direct normal irradiance, 1-min avg(short_direct_normal)
• Upwelling Shortwave Hemispheric Irradiance, Unventilated Pyranometer, Maxima(up_short_hemisp_max)
• Shortwave Direct Normal Irradiance, Pyrheliometer, Minima(short_direct_normal_min)
• short_direct_normal_std
• Shortwave Direct Normal Irradiance, Pyrheliometer, Maxima(short_direct_normal_max)
• down_short_diffuse_hemisp_std
• Downwelling Shortwave Diffuse Hemisp. Irrad., Ventilated Pyranometer, Minima(down_short_diffuse_hemisp_min)
• Radiation, shortwave, downwelling total hemispheric irradiance, 1-min avg(down_short_hemisp)
• Downwelling Shortwave Hemispheric Irradiance, Ventilated Pyranometer, Minima(down_short_hemisp_min)
• Downwelling Shortwave Diffuse Hemisp. Irrad., Ventilated Pyranometer, Maxima(down_short_diffuse_hemisp_max)
• Downwelling Shortwave Hemispheric Irradiance, Ventilated Pyranometer, Maxima(down_short_hemisp_max)
• Upwelling Shortwave Hemispheric Irradiance, Unventilated Pyranometer, Minima(up_short_hemisp_min)
• Radiation, shortwave, at 10-m height, upwelling hemispheric irrad., 1-min avg(up_short_hemisp)
• down_short_hemisp_std
• Radiation, shortwave, downwelling diffuse hemispheric irradiance, 1-min avg(down_short_diffuse_hemisp)

SGP/SIRS/E11 - Reprocessed: Incorrect upwelling longwave calibrations

Incorrect calibration coefficients were applied to the upwelling longwave measurements due 
to an error in the instrument configuration file.

The data have been reprocessed to apply corrected calibrations.  The reprocessed data were 
archived in August 2006.

• Upwelling Longwave Hemispheric Irradiance, Unventilated Pyrgeometer, Maxima(up_long_hemisp_max)
• up_long_hemisp_std
• Upwelling Longwave Hemispheric Net Infrared(up_long_netir)
• Radiation, longwave, at 10-m height, upwelling hemispheric irrad., 1-min avg(up_long_hemisp)
• Upwelling Longwave Hemispheric Irradiance, Unventilated Pyrgeometer, Minima(up_long_hemisp_min)

SGP/SIRS/E11 - Reprocessed: Longwave Calibration error

Modified pyrgeometer calibration procedures were implemented beginning in February 2004. 
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 have been reprocessed to 
remove the calibration bias.  The reprocessed 60 second averaged data are based on 3 
instantaneous 20 second data records rather than on 60 1 second instantaneous data records. 
Still, these data are considered far superior to the originally processed data. The 
reprocessed data were archived in August 2006.

• Downwelling Longwave Hemispheric Net Infrared(down_long_netir)
• Upwelling Longwave Hemispheric Net Infrared(up_long_netir)
• Downwelling Longwave Hemispheric Irradiance, Shaded Ventilated Pyrgeometer(down_long_hemisp_shaded)
• Radiation, longwave, at 10-m height, upwelling hemispheric irrad., 1-min avg(up_long_hemisp)