SGP/SIRS/E2 - Reprocess: Incorrect shortwave radiometer calibration coefficients

During the pyrgeometer instrument (PIR) changout a datalogger program was loaded with 
incorrect calibration coefficients for the shortwave instruments.  The affected measurements 
were : downwelling diffuse (DD), upwelling shortwave(US), direct normal (NIP) and 
downwelling shortwave(DS)

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)*118.11
US(corrected) = (US/113.19)*118.21
NIP(corrected)= (NIP/120.17)*119.08
DS(corrected) = (DS/118.46)*117.33

• Downwelling Shortwave Diffuse Hemispheric Irradiance, Ventilated Pyranometer,
  Maxima(down_short_diffuse_hemisp_max)
• Upwelling (10 meter) Shortwave Hemispheric Irradiance, Ventilated Pyranometer,
  Maxima(up_short_hemisp_max)
• Shortwave Direct Normal Irradiance, Pyrheliometer, Minima(short_direct_normal_min)
• Downwelling Shortwave Hemispheric Irradiance, Ventilated Pyrgeometer, Minima(down_short_hemisp_min)
• Downwelling Shortwave Hemispheric Irradiance, Ventilated Pyrgeometer, Maxima(down_short_hemisp_max)
• Downwelling Shortwave Diffuse Hemispheric Irradiance, Ventilated Pyranometer,
  Minima(down_short_diffuse_hemisp_min)
• Shortwave Direct Normal Irradiance, Pyrheliometer(short_direct_normal)
• Upwelling (10 meter) Shortwave Hemispheric Irradiance, Ventilated Pyranometer,
  Minima(up_short_hemisp_min)
• Shortwave Direct Normal Irradiance, Pyrheliometer, Standard Deviation(short_direct_normal_std)
• Upwelling (10 meter) Shortwave Hemispheric Irradiance, Ventilated Pyranometer,
  Standard Deviation(up_short_hemisp_std)
• Downwelling Shortwave Hemispheric Irradiance, Ventilated Pyrgeometer(down_short_hemisp)
• Shortwave Direct Normal Irradiance, Pyrheliometer, Maxima(short_direct_normal_max)
• Downwelling Shortwave Hemispheric Irradiance, Ventilated Pyrgeometer, Standard
  Deviation(down_short_hemisp_std)
• Downwelling Shortwave Diffuse Hemispheric Irradiance, Ventilated Pyranometer(down_short_diffuse_hemisp)
• Upwelling (10 meter) Shortwave Hemispheric Irradiance, Ventilated Pyranometer(up_short_hemisp)
• Downwelling Shortwave Diffuse Hemispheric Irradiance, Ventilated Pyranometer,
  Standard Deviation(down_short_diffuse_hemisp_std)

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

SGP/SIRS/E2 - Reprocess: Incorrect DIR calibration coefficients

During the DIR/UIR instrument changeout on 2/10/2005 the new datalogger program contained 
incorrect calibration coefficients for the DIR instrument. Technicians corrected the 
program on 3/10/2005.

Users may wish to attempt to reprocess the data by applying the following method. Note, 
this may result in additional errors due to the averaging of the 20s data.

Use 20s data (available averaged in 60s b1 file) to reconstruct downwelling
IR (DIR) data from the PIR instrument.  Use case and dome temperatures as supplied in 
variables:
   inst_down_long_dome_temp[K]
   inst_down_long_case_temp[K]
Back out thermopile(tp) output in mV from the tp in W/m2 as described:
   tp[mV] = (down_long_netir[W/m2]/WrongK1[W/(m2*uV)])/1000
where WrongK1 is the K1 term applied to the DIR during the DQR period.  Use the following 
coefficients to recreate the dataset following the described method in the SIRS handbook 
Sec 7.1.2 available at http://www.arm.gov/instruments/instrument.php?id=33 

The coefficients to be used are as follows:
   WrongK1 = .2251
   K0 = -26.00
   K1 = .2680
   K2 = 1.056
   K3 = -2.476
   Kr = 7.044E-4

• Downwelling Longwave Hemispheric Irradiance, Shaded Pyrgeometer, Standard
  Deviation(down_long_hemisp_shaded_std)
• Instantaneous Downwelling Pyrgeometer Case Thermistor Temperature, Shaded
  Pyrgeometer(inst_down_long_shaded_case_temp)
• Downwelling Longwave Hemispheric Net Infrared(down_long_netir)
• Downwelling Longwave Hemispheric Irradiance, Shaded Pyrgeometer, Maxima(down_long_hemisp_shaded_max)
• Downwelling Longwave Hemispheric Irradiance, Shaded Pyrgeometer(down_long_hemisp_shaded)
• Instantaneous Downwelling Pyrgeometer Dome Thermistor Temperature, Shaded
  Pyrgeometer(inst_down_long_shaded_dome_temp)
• Downwelling Longwave Hemispheric Irradiance, Shaded Pyrgeometer, Minima(down_long_hemisp_shaded_min)

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

• Instantaneous Downwelling Pyrgeometer Dome Thermistor Resistance, Shaded
  Pyrgeometer(inst_down_long_shaded_dome_resist)
• Instantaneous Downwelling Pyrgeometer Thermopile Voltage, Shaded Pyrgeometer(inst_down_long_hemisp_shaded_tp)
• Instantaneous Downwelling Pyrgeometer Case Thermistor Resistance, Shaded
  Pyrgeometer(inst_down_long_shaded_case_resist)

SGP/SIRS/E2 - 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)
• Upwelling Longwave Hemispheric Net Infrared(up_long_netir)
• Downwelling Longwave Hemispheric Net Infrared(down_long_netir)
• Downwelling Longwave Hemispheric Irradiance, Shaded Pyrgeometer(down_long_hemisp_shaded)