SGP/SIRS/E5 - NIP obstruction around sunrise

Due to instrument supports blocking the NIP, the short_direct_normal measurement readings 
dip for about 15 minutes at approximately 1200 UTC (at or near sunrise) on clear days 
during the bracketed time ranges for the entire duration of this deployment.  Affected time 
periods are 4/15-5/15 and 7/28-8/27 annually.

The instrument was removed from service 20091102.

• inst_direct_normal

• Shortwave Direct Normal Irradiance, Pyrheliometer, Minima(short_direct_normal_min)
• Shortwave Direct Normal Irradiance, Pyrheliometer, Maxima(short_direct_normal_max)
• short_direct_normal_std
• Radiation, shortwave, direct normal irradiance, 1-min avg(short_direct_normal)

SGP/SIRS/E1 - Reprocess: incorrect calibration coefficients for US (upwelling shortwave) 
instrument

During the changeover from 4 to 1 coefficient for the PIRs at SIRS/E1 (PIF) the datalogger 
program was programmed with the wrong calibration coefficient and serial number for the 
US PSP instrument measuring the Upwelling Hemispheric Shortwave radiation. The 
calibration coefficient was 114.43 W/m2/mV (instrument 30618F3) when it should have been 
104.47W/m2/mV (instrument 29618F3)

• Raw data stream - documentation not supported

• Radiation, shortwave, at 10-m height, upwelling hemispheric irrad., 1-min avg(up_short_hemisp)
• up_short_hemisp_std
• Upwelling Shortwave Hemispheric Irradiance, Unventilated Pyranometer, Minima(up_short_hemisp_min)
• Upwelling Shortwave Hemispheric Irradiance, Unventilated Pyranometer, Maxima(up_short_hemisp_max)

SGP/SIRS/E1 - Intermittantly missing downwelling diffuse

Starting on or about 10/26/2005 the downwelling diffuse hemispheric irradiance (Eppley 
8-48) instrument had intermittant missing values. Technicians found a loose wire on the 
instrument connector and repaired it on 4/4/2006. 

Use global shortwave hemispheric (PSP) component - normal incident component (CosZA*NIP) 
to calulate diffuse component.  Comparison of absolute difference between actual and 
computed diffuse component values and diffuse standard deviations > 1-2 W/m2 can help filter 
the noisy diffuse data.  There is no standard method.

• Raw data stream - documentation not supported

• inst_diffuse

• down_short_diffuse_hemisp_std
• Downwelling Shortwave Diffuse Hemisp. Irrad., Ventilated Pyranometer, Minima(down_short_diffuse_hemisp_min)
• Downwelling Shortwave Diffuse Hemisp. Irrad., Ventilated Pyranometer, Maxima(down_short_diffuse_hemisp_max)
• Radiation, shortwave, downwelling diffuse hemispheric irradiance, 1-min avg(down_short_diffuse_hemisp)

SGP/SIRS/E11 - failed ventilator fan

E11 downwelling hemispheric shortwave instrument (Eppley PSP) has shown larger and larger 
nighttime offsets (from -5 to -10 W/m2) since October. A failed ventilator fan was 
discovered during PM and replaced on 4/4/2006.

• inst_global

• Downwelling Shortwave Hemispheric Irradiance, Ventilated Pyranometer, Minima(down_short_hemisp_min)
• Radiation, shortwave, downwelling total hemispheric irradiance, 1-min avg(down_short_hemisp)
• Downwelling Shortwave Hemispheric Irradiance, Ventilated Pyranometer, Maxima(down_short_hemisp_max)
• down_short_hemisp_std

• Raw data stream - documentation not supported

SGP/SIRS/E19 - Ventilator failure

Dowenlling shortwave hemispheric instrument signal (Eppley PSP) is very erratic due to 
failed ventilator fan which was replaced during PM on 04/13/2006.

• Raw data stream - documentation not supported

• inst_global

• Downwelling Shortwave Hemispheric Irradiance, Ventilated Pyranometer, Minima(down_short_hemisp_min)
• down_short_hemisp_std
• Downwelling Shortwave Hemispheric Irradiance, Ventilated Pyranometer, Maxima(down_short_hemisp_max)
• Radiation, shortwave, downwelling total hemispheric irradiance, 1-min avg(down_short_hemisp)

SGP/SIRS/E20 - Instrument noise problem

Afer recovery from lightening strike the upwelling longwave SIRS Eppley PIR (UIR) has had 
noise on both dome and case thermistor measurements.  On 4/12/2006 techs replaced 
defective j-panel at base of tower.

• Raw data stream - documentation not supported

• Upwelling Longwave Hemispheric Irradiance, Unventilated Pyrgeometer, Maxima(up_long_hemisp_max)
• 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)
• inst_up_long_case_temp
• inst_up_long_dome_temp
• up_long_hemisp_std
• Upwelling Longwave Hemispheric Net Infrared(up_long_netir)

• inst_up_long_case_resist
• inst_up_long_hemisp_tp
• inst_up_long_dome_resist

SGP/SIRS/E24 - Reprocess: Incorrect calibration coefficients

During the PIR coefficient change from 4/coeffs to 1/coeff, the downwelling diffuse 
hemispheric instrument (Eppley 8-48) coefficient was inadvertently changed to 122.85 and should 
have been 112.85 W/m2/mV. 

Perform the following calculation to correct the data, DD=downwelling diffuse instrument:  

  DD(new)[W/m2]=( DD(old)[W/m2]/122.85[W/m2\mV] )* 112.85[W/m2/mV]

• Raw data stream - documentation not supported

• Downwelling Shortwave Diffuse Hemisp. Irrad., Ventilated Pyranometer, Minima(down_short_diffuse_hemisp_min)
• Radiation, shortwave, downwelling diffuse hemispheric irradiance, 1-min avg(down_short_diffuse_hemisp)
• down_short_diffuse_hemisp_std
• Downwelling Shortwave Diffuse Hemisp. Irrad., Ventilated Pyranometer, Maxima(down_short_diffuse_hemisp_max)

• inst_diffuse

SGP/SIRS/E21 - Roosting birds in field of view

The RBDD (Rotating Bird Deterrent Device) installed at E21 to prevent turkey vultures from 
roosting on the instrument boom failed resulting in noisy NIP (Short Direct Normal) and 
PSP (Short Global Hemispheric) data and a spike occurring around 2230 UTC everyday due to 
obstruction of the field of view.

Problem is intermittant due to moving birds.  Use data with discretion.  Follow ARM 
(DQMS3) flag recommendations for QC flags 02 or 03 found in section 5.1.4 of the SIRS handbook:
http://www.arm.gov/publications/tech_reports/handbooks/sirs_handbook.pdf

• inst_global
• inst_direct_normal

• Raw data stream - documentation not supported

• short_direct_normal_std
• Shortwave Direct Normal Irradiance, Pyrheliometer, Minima(short_direct_normal_min)
• Shortwave Direct Normal Irradiance, Pyrheliometer, Maxima(short_direct_normal_max)
• Downwelling Shortwave Hemispheric Irradiance, Ventilated Pyranometer, Minima(down_short_hemisp_min)
• Radiation, shortwave, direct normal irradiance, 1-min avg(short_direct_normal)
• Radiation, shortwave, downwelling total hemispheric irradiance, 1-min avg(down_short_hemisp)
• Downwelling Shortwave Hemispheric Irradiance, Ventilated Pyranometer, Maxima(down_short_hemisp_max)
• down_short_hemisp_std

SGP/SIRS/E16 - NIP Instrument Failure

The short_direct_normal dropped below MIN value on 4/28/06 resulting in failure of the 
up_long_hemisp started 3-component test.  No data are available from 20060428.1900 through 
20060503.21:39.  When the data returned, the short_direct normal fluctuated wildly 
throughout the day, and down_long_hemisp & up_long_hemisp failed the 3-component test.  
Technicians determined the NIP had failed and replaced it 5/12.

Use component method ((global - diffuse)/cos(ZA)) to calculate direct normal. For more 
information on this summation method please see section 7.2 (Theory of Operation) of the 
SIRS Handbook:
http://www.arm.gov/publications/tech_reports/handbooks/sirs_handbook.pdf

• Shortwave Direct Normal Irradiance, Pyrheliometer, Minima(short_direct_normal_min)
• Shortwave Direct Normal Irradiance, Pyrheliometer, Maxima(short_direct_normal_max)
• short_direct_normal_std
• Radiation, shortwave, direct normal irradiance, 1-min avg(short_direct_normal)

• inst_direct_normal

SGP/SIRS/E8 - Instrument cable problem

The short_direct_normal, down_short_diffuse_hemisp and up_short_hemisp data are missing or 
are spiking to negative numbers.  On 20060530, technicians discovered cows had chewed on 
the instrument cables.

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

• inst_direct_normal
• inst_up_short_hemisp
• inst_diffuse

SGP/SIRS/E3 - Reprocessed: Longwave Calibration error

Modified pyrgeometer calibration procedures were implemented beginning in March 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.

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

SGP/SIRS/E4 - Reprocessed: Longwave Calibration error

Modified pyrgeometer calibration procedures were implemented beginning in March 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 October 2006.

• Upwelling Longwave Hemispheric Net Infrared(up_long_netir)
• Downwelling Longwave Hemispheric Net Infrared(down_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)

SGP/SIRS/E5 - Reprocessed: Longwave Calibration error

Modified pyrgeometer calibration procedures were implemented beginning in March 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 October 2006.

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

SGP/SIRS/E6 - Reprocessed: Longwave Calibration error

Modified pyrgeometer calibration procedures were implemented beginning in March 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 October 2006.

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

SGP/SIRS/E7 - 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 October 2006.

• 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)
• Upwelling Longwave Hemispheric Net Infrared(up_long_netir)
• Downwelling Longwave Hemispheric Net Infrared(down_long_netir)

SGP/SIRS/E8 - 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 instanteous data records. 
Still, these data are considered far superior to the originally processed data. The 
reprocessed data were archived in September 2006.

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

SGP/SIRS/E9 - Reprocessed: 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 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 instanteous data records. 
Still, these data are considered far superior to the originally processed data. The 
reprocessed data were archived in October 2006.

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

SGP/SIRS/E10 - 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)

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)

SGP/SIRS/E12 - Reprocessed: Longwave Calibration error

Modified pyrgeometer calibration procedures were implemented beginning in July 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 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 October 2006.

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

SGP/SIRS/E13 - Reprocessed: 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 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 October 2006.

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

SGP/SIRS/E15 - Reprocessed: Longwave Calibration error

Modified pyrgeometer calibration procedures were implemented beginning in July 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 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 October 2006.

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

SGP/SIRS/E16 - Reprocessed: Longwave Calibration error

Modified pyrgeometer calibration procedures were implemented beginning in July 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 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 October 2006.

• 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)
• Upwelling Longwave Hemispheric Net Infrared(up_long_netir)
• Downwelling Longwave Hemispheric Net Infrared(down_long_netir)

SGP/SIRS/E18 - Reprocessed: Longwave Calibration error

Modified pyrgeometer calibration procedures were implemented beginning in July 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 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 October 2006.

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

SGP/SIRS/E19 - Reprocessed: Longwave Calibration error

Modified pyrgeometer calibration procedures were implemented beginning in July 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 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 October 2006.

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

SGP/SIRS/E20 - Reprocessed: Longwave Calibration error

Modified pyrgeometer calibration procedures were implemented beginning in July 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 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 November 2006.

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

SGP/SIRS/E21 - Reprocessed: Longwave Calibration error

Modified pyrgeometer calibration procedures were implemented beginning in July 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 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 November 2006.

• 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)
• Upwelling Longwave Hemispheric Net Infrared(up_long_netir)
• Downwelling Longwave Hemispheric Net Infrared(down_long_netir)

SGP/SIRS/E22 - Reprocessed: Longwave Calibration error

Modified pyrgeometer calibration procedures were implemented beginning in July 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 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)
• 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)
• Upwelling Longwave Hemispheric Net Infrared(up_long_netir)

SGP/SIRS/E24 - Reprocessed: Longwave Calibration error

Modified pyrgeometer calibration procedures were implemented beginning in July 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 October 2006.

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

SGP/SIRS/E27 - Reprocessed: Longwave Calibration error

Modified pyrgeometer calibration procedures were implemented beginning in May 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 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 October 2006.

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

SGP/SIRS/C1 - Reprocessed: 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 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 October 2006.

• Upwelling Longwave Hemispheric Net Infrared(up_long_netir)
• Downwelling Longwave Hemispheric Net Infrared(down_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)

SGP/SIRS/E1 - 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 October 2006.

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

SGP/SIRS/E3 - Reprocess: Wrong Calibration Coefficients

No data were collected from 6/7/2006 0000 to 6/14/2006 1612 due to hardware problems.  
When data resumed on 6/14, ALL calibration coefficients and serial numbers were for 
different instruments possibly due to incorrect program loaded on storage module.  Correct 
program reloaded by PM/CM techs on 7/12 1830GMT

Shortwave data can be corrected with a simple multiplier as shown below.  Longwave data 
must be reprocessed from temperature and netIR data.

The data can be recalibrated as follows:
First divide value by incorrectly applied cal coeff (first number) then multiply by 
correct cal coeff (second number). 
  down_short_diffuse_hemisp	109.52	110.31
  up_short_hemisp		111.61	109.80
  short_direct_normal		115.73	118.82
  down_short_hemisp		122.47	117.34
  up_long_netir 		0.26525 0.2564
  down_long_netir		0.27173	0.2695

Reapply cal coeffs below using up_long_netIR(uV), inst_up_long_dome_temp(K),  
inst_up_long_dome_temp(K) using procedure described in SIRS instrument manual.
  up_long_hemisp
	k0	0.00 W/m^2
	k1	0.2564 W/(m^2*uV)
	k2	1.00 unitless
	k3	-4.00 unitless
	kr	0.000 K/uV

Reapply cal coeffs below using down_long_netIR(uV),inst_down_long_dome_temp
(K),inst_down_long_dome_temp(K).
  down_long_hemisp_shaded	
	k0	0.00 W/m^2
	k1	0.2695 W/(m^2*uV)
	k2	1.00 unitless
	k3	-4.00 unitless
	kr	0.000 K/uV

• inst_down_long_shaded_dome_resist
• Irradiance, longwave, downwelling, hemispheric, thermopile (Shaded Pyrgeometer1)(inst_down_long_hemisp_shaded_tp)
• inst_up_long_dome_resist
• inst_up_short_hemisp
• inst_up_long_case_resist
• inst_diffuse
• inst_global
• inst_direct_normal
• inst_down_long_shaded_case_resist
• inst_up_long_hemisp_tp

• Radiation, shortwave, downwelling total hemispheric irradiance, 1-min avg(down_short_hemisp)
• Radiation, longwave, at 10-m height, upwelling hemispheric irrad., 1-min avg(up_long_hemisp)
• inst_down_long_shaded_dome_temp
• up_long_hemisp_std
• Upwelling Longwave Hemispheric Irradiance, Unventilated Pyrgeometer, Maxima(up_long_hemisp_max)
• inst_up_long_dome_temp
• Downwelling Shortwave Diffuse Hemisp. Irrad., Ventilated Pyranometer, Minima(down_short_diffuse_hemisp_min)
• Radiation, shortwave, direct normal irradiance, 1-min avg(short_direct_normal)
• down_short_diffuse_hemisp_std
• inst_down_long_shaded_case_temp
• down_short_hemisp_std
• Shortwave Direct Normal Irradiance, Pyrheliometer, Minima(short_direct_normal_min)
• Shortwave Direct Normal Irradiance, Pyrheliometer, Maxima(short_direct_normal_max)
• Downwelling Longwave Hemispheric Irrad., Shaded Ventilated Pyrgeometer, Minima(down_long_hemisp_shaded_min)
• Downwelling Longwave Hemispheric Irrad., Shaded Ventilated Pyrgeometer, Maxima(down_long_hemisp_shaded_max)
• short_direct_normal_std
• Downwelling Longwave Hemispheric Irradiance, Shaded Ventilated Pyrgeometer(down_long_hemisp_shaded)
• Upwelling Longwave Hemispheric Net Infrared(up_long_netir)
• Downwelling Longwave Hemispheric Net Infrared(down_long_netir)
• Downwelling Shortwave Diffuse Hemisp. Irrad., Ventilated Pyranometer, Maxima(down_short_diffuse_hemisp_max)
• down_long_hemisp_shaded_std
• Upwelling Longwave Hemispheric Irradiance, Unventilated Pyrgeometer, Minima(up_long_hemisp_min)
• Radiation, shortwave, at 10-m height, upwelling hemispheric irrad., 1-min avg(up_short_hemisp)
• Upwelling Shortwave Hemispheric Irradiance, Unventilated Pyranometer, Minima(up_short_hemisp_min)
• Downwelling Shortwave Hemispheric Irradiance, Ventilated Pyranometer, Maxima(down_short_hemisp_max)
• up_short_hemisp_std
• Downwelling Shortwave Hemispheric Irradiance, Ventilated Pyranometer, Minima(down_short_hemisp_min)
• inst_up_long_case_temp
• Radiation, shortwave, downwelling diffuse hemispheric irradiance, 1-min avg(down_short_diffuse_hemisp)
• Upwelling Shortwave Hemispheric Irradiance, Unventilated Pyranometer, Maxima(up_short_hemisp_max)

SGP/SIRS/E9 - Tracker Failure

On July 12th the SIRS tracker failed to wake up that morning.  On the 21st of July CM 
repaired the tracker.

• inst_direct_normal
• inst_diffuse

• Shortwave Direct Normal Irradiance, Pyrheliometer, Maxima(short_direct_normal_max)
• Radiation, shortwave, direct normal irradiance, 1-min avg(short_direct_normal)
• Downwelling Shortwave Diffuse Hemisp. Irrad., Ventilated Pyranometer, Maxima(down_short_diffuse_hemisp_max)
• Radiation, shortwave, downwelling diffuse hemispheric irradiance, 1-min avg(down_short_diffuse_hemisp)
• Downwelling Shortwave Diffuse Hemisp. Irrad., Ventilated Pyranometer, Minima(down_short_diffuse_hemisp_min)
• short_direct_normal_std
• down_short_diffuse_hemisp_std
• Shortwave Direct Normal Irradiance, Pyrheliometer, Minima(short_direct_normal_min)

• Raw data stream - documentation not supported

SGP/SIRS/E18 - Upwelling SW cable severed

The Upwelling Shortwave signal was exceeding physical limits.  Ops reported the upwelling 
shortwave cable was damaged by rodents. The cable was repaired and returned to service.

• inst_up_short_hemisp

• Upwelling Shortwave Hemispheric Irradiance, Unventilated Pyranometer, Maxima(up_short_hemisp_max)
• Radiation, shortwave, at 10-m height, upwelling hemispheric irrad., 1-min avg(up_short_hemisp)
• up_short_hemisp_std
• Upwelling Shortwave Hemispheric Irradiance, Unventilated Pyranometer, Minima(up_short_hemisp_min)

• Raw data stream - documentation not supported

SGP/SIRS/C1 - Upwelling SW cable problem

Starting 11/13/2006, the C1 SIRS Upwelling Shortwave (up_short_hemisp) started to show 
large differences in comparison to co-located E13 SIRS and C1 IRT25m.  After much 
troubleshooting and gnashing of teeth it was discovered that rodents had chewed through the 
instrument cables at the bottom of the tilt tower. Cables were replaced 01/23/2007 1930GMT.

• inst_up_short_hemisp

• Raw data stream - documentation not supported

• Radiation, shortwave, at 10-m height, upwelling hemispheric irrad., 1-min avg(up_short_hemisp)
• up_short_hemisp_std
• Upwelling Shortwave Hemispheric Irradiance, Unventilated Pyranometer, Minima(up_short_hemisp_min)
• Upwelling Shortwave Hemispheric Irradiance, Unventilated Pyranometer, Maxima(up_short_hemisp_max)

SGP/SIRS/E24 - Spikes in data

The down_short_hemisp, down_long_hemisp, and upwelling_longwave showed large spikes (an 
order of magnitude) in data.  Problem corrected itself on 12/5 before the site visit on 
12/7.  It is not known why the problem did not return but instruments affected were on the 
multiplexer.  Maintenance reports it was not replaced.

• Downwelling Longwave Hemispheric Irrad., Shaded Ventilated Pyrgeometer, Minima(down_long_hemisp_shaded_min)
• Downwelling Longwave Hemispheric Net Infrared(down_long_netir)
• Downwelling Shortwave Hemispheric Irradiance, Ventilated Pyranometer, Maxima(down_short_hemisp_max)
• Radiation, shortwave, downwelling total hemispheric irradiance, 1-min avg(down_short_hemisp)
• down_long_hemisp_shaded_std
• Upwelling Longwave Hemispheric Net Infrared(up_long_netir)
• Upwelling Longwave Hemispheric Irradiance, Unventilated Pyrgeometer, Maxima(up_long_hemisp_max)
• inst_up_long_case_temp
• inst_up_long_dome_temp
• up_long_hemisp_std
• Downwelling Longwave Hemispheric Irradiance, Shaded Ventilated Pyrgeometer(down_long_hemisp_shaded)
• down_short_hemisp_std
• Radiation, longwave, at 10-m height, upwelling hemispheric irrad., 1-min avg(up_long_hemisp)
• Downwelling Longwave Hemispheric Irrad., Shaded Ventilated Pyrgeometer, Maxima(down_long_hemisp_shaded_max)
• Downwelling Shortwave Hemispheric Irradiance, Ventilated Pyranometer, Minima(down_short_hemisp_min)
• Upwelling Longwave Hemispheric Irradiance, Unventilated Pyrgeometer, Minima(up_long_hemisp_min)
• inst_down_long_shaded_case_temp
• inst_down_long_shaded_dome_temp

• inst_down_long_shaded_dome_resist
• inst_up_short_hemisp
• inst_up_long_dome_resist
• inst_global
• Irradiance, longwave, downwelling, hemispheric, thermopile (Shaded Pyrgeometer1)(inst_down_long_hemisp_shaded_tp)
• inst_up_long_hemisp_tp
• inst_up_long_case_resist
• inst_down_long_shaded_case_resist

SGP/SIRS/E7 - Instrument noise

Beginning around 10/31, the E7 UIR experienced an increasingly noisy signal.  The 
thermopile signal was noisy, but case and dome thermistors are well behaved.  Maintenance 
reseated the UIR cable connections on 12/12/2006 which effectively eliminated the UIR noise.

The thermopile data from the upwelling pyrgeometer is noisy with resulting irradiance 
variations of up to 5 W/m2, but doesn't appear to have a bias.

• inst_up_long_hemisp_tp
• inst_up_long_case_resist
• inst_up_long_dome_resist

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

SGP/SIRS/C1 - Reprocess: Incorrect calibration coefficients

Incorrection calibration coefficients were used in the C1/SIRS datalogger program. The 
PSP-US (upwelling shortwave global hemispheric), 30943F3 should be 126.93 not 129.93 
[W/m2/mV].

• inst_up_short_hemisp

• Raw data stream - documentation not supported

• Radiation, shortwave, at 10-m height, upwelling hemispheric irrad., 1-min avg(up_short_hemisp)
• up_short_hemisp_std
• Upwelling Shortwave Hemispheric Irradiance, Unventilated Pyranometer, Minima(up_short_hemisp_min)
• Upwelling Shortwave Hemispheric Irradiance, Unventilated Pyranometer, Maxima(up_short_hemisp_max)

SGP/SIRS/E22 - Reprocess: Incorrect calibration coefficients

NIP (short_direct_normal) 29541E6 had an incorrect calibration coefficient in the logger 
program. 128.97 should have been 126.67 [W/m2/mV].

• inst_direct_normal

• Raw data stream - documentation not supported

• Shortwave Direct Normal Irradiance, Pyrheliometer, Maxima(short_direct_normal_max)
• Shortwave Direct Normal Irradiance, Pyrheliometer, Minima(short_direct_normal_min)
• short_direct_normal_std
• Radiation, shortwave, direct normal irradiance, 1-min avg(short_direct_normal)

SGP/SIRS/E3 - Instrument leveling and tracker problem

Asymmetry between measured downwelling shortwave and derived downwelling shortwave 
hemispheric in the afternoon began late in fall and became more apparent as the sun moved higher 
in spring.  This can happen when the PSP is unlevel or when the NIP is not tracking well. 

The PSP level was corrected and the clock on tracker was reset.  Mentor suspects PSP was 
unlevel during this time range causing the discrepancy in measured vs. calculated 
downwelling shortwave hemispheric data.

• inst_global
• inst_direct_normal
• inst_diffuse

• Radiation, shortwave, downwelling total hemispheric irradiance, 1-min avg(down_short_hemisp)
• Downwelling Shortwave Diffuse Hemisp. Irrad., Ventilated Pyranometer, Minima(down_short_diffuse_hemisp_min)
• Radiation, shortwave, direct normal irradiance, 1-min avg(short_direct_normal)
• Downwelling Shortwave Diffuse Hemisp. Irrad., Ventilated Pyranometer, Maxima(down_short_diffuse_hemisp_max)
• down_short_diffuse_hemisp_std
• down_short_hemisp_std
• Downwelling Shortwave Hemispheric Irradiance, Ventilated Pyranometer, Maxima(down_short_hemisp_max)
• Shortwave Direct Normal Irradiance, Pyrheliometer, Minima(short_direct_normal_min)
• Downwelling Shortwave Hemispheric Irradiance, Ventilated Pyranometer, Minima(down_short_hemisp_min)
• Shortwave Direct Normal Irradiance, Pyrheliometer, Maxima(short_direct_normal_max)
• short_direct_normal_std
• Radiation, shortwave, downwelling diffuse hemispheric irradiance, 1-min avg(down_short_diffuse_hemisp)