SGP/SIRS/E24 - Reprocess: Incorrect calibration coefficients

Calibration coefficient for the downwelling diffuse measurement (8-48 B&W Eppley 
instrument) was incorrect after the instrument replacement 8/18/2005.

Affected downwelling diffuse irradiance data can be corrected:
Irr(corr) = Irr(uncorr) / 122.85 * 112.85 (or a overall multiplier of .9186)

• null(Raw data stream - documentation not supported)

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

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

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