SGP/SIRS/E1 - broken cable on DSDH (aka DD) measurment instrument - Eppley 8-48.

Occasionally, the downwelling shortwave diffuse hemispheric (DSDH) readings spike to 
unreasonably low levels, causing derived downwelling shortwave hemispheric (DSH) readings to 
spike well below the actual DSH readings.  Technicians repaired the DSDH instument (an 
Eppley 8-48) cable on 02/08/2005 2055GMT.  There have been no dropouts since that time.

• Instantaneous Uncorrected Downwelling Shortwave Diffuse, Shaded Pyranometer
  Thermopile Voltage(inst_diffuse)

• Downwelling Shortwave Diffuse Hemispheric Irradiance, Ventilated Pyranometer,
  Standard Deviation(down_short_diffuse_hemisp_std)
• Downwelling Shortwave Diffuse Hemispheric Irradiance, Ventilated Pyranometer,
  Minima(down_short_diffuse_hemisp_min)
• Downwelling Shortwave Diffuse Hemispheric Irradiance, Ventilated Pyranometer,
  Maxima(down_short_diffuse_hemisp_max)
• Downwelling Shortwave Diffuse Hemispheric Irradiance, Ventilated Pyranometer(down_short_diffuse_hemisp)

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

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.

• Instantaneous Uncorrected Downwelling Shortwave Diffuse, Shaded Pyranometer
  Thermopile Voltage(inst_diffuse)

• Downwelling Shortwave Diffuse Hemispheric Irradiance, Ventilated Pyranometer,
  Standard Deviation(down_short_diffuse_hemisp_std)
• Downwelling Shortwave Diffuse Hemispheric Irradiance, Ventilated Pyranometer,
  Minima(down_short_diffuse_hemisp_min)
• Downwelling Shortwave Diffuse Hemispheric Irradiance, Ventilated Pyranometer,
  Maxima(down_short_diffuse_hemisp_max)
• Downwelling Shortwave Diffuse Hemispheric Irradiance, Ventilated Pyranometer(down_short_diffuse_hemisp)

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

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 (10 meter) Longwave Hemispheric Irradiance, Ventilated Pyrgeometer(up_long_hemisp)
• Downwelling Longwave Hemispheric Irradiance, Shaded Pyrgeometer(down_long_hemisp_shaded)
• Upwelling Longwave Hemispheric Net Infrared(up_long_netir)
• Downwelling Longwave Hemispheric Net Infrared(down_long_netir)