SGP/SIRS/E4 - Dirt on Dome

The downwelling shortwave hemispheric radiation data are suspect.  The PSP dome appears to 
have been very dirty, especially during times when the sun angles were low.

• null(Raw data stream - documentation not supported)

• Downwelling Shortwave Hemispheric Irradiance, Ventilated Pyranometer, Minima(down_short_hemisp_min)
• Down-welling unshaded pyranometer voltage(down_short_hemisp)
• Downwelling Shortwave Hemispheric Irradiance, Ventilated Pyranometer, Maxima(down_short_hemisp_max)
• Downwelling Shortwave Hemispheric Irradiance, Ventilated Pyranometer, Standard
  Deviation(down_short_hemisp_std)

• Instantaneous Downwelling Hemispheric Shortwave, Unshaded Pyranometer Thermopile
  Voltage(inst_global)

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 (10 meter) Longwave Hemispheric Irradiance, 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)