Reference Broadband Shortwave Data at SGP Central Cluster during Fall IOP '97

This is a recommendation for the best available broadband shortwave data from the SGP 
Central Cluster (Lamont, OK) during the Combined Fall IOP, 15 Sept - 5 Oct 1997.

Data available from the SGP Radiometer Calibration Facility (RCF) has lower measurement 
uncertainties than similar measurements from the C1, E-13, and BSRN/BRS platforms.

The RCF data were collected using the same Broadband Outdoor Radiometer CALibration 
(BORCAL) system used for routine calibration of pyranometers and pyrheliometers at the RCF.  
The data are available for 30-second interval.  
Direct normal irradiance measurements from a windowed RCF Absolute Cavity Radiometer 
during the IOP is considered more accurate (+/- 0.5%) than the Normal Incidence Pyrheliometers 
(NIP) at the Central Cluster (+/- 2%).
The Automated Hickey-Frieden cavity radiometer is electrically self-calibrating and 
provides reference standard data suitable for the calibration of the NIPs used at all the CART 
sites.

Diffuse horizontal irradiance is available as the average of two Eppley Precision Spectral 
Pyranometers and is considered slightly more accurate than the downwelling diffuse (DD) 
data from the Central Cluster instruments.
The RCF data will have periodic gaps during the electrical calibration intervals (about 
6-10 minutes, 4 or 5 times per day).
The reference global horizontal (or Downwelling Shortwave - DS) has been computed from the 
measured direct normal and diffuse components:
DS = NIP x Cos(Z) + DD,
where, Z = solar zenith angle.

All RCF data collected during the IOP are on the ARM IOP Web page 
(iop.archive.arm.gov/arm-iop). 
with other data from the Fall97 shortwave IOP.

Additional corrections to the diffuse data may be possible after researching PSP nighttime 
offsets.

Data from C1, E-13, and BSRN/BRS platforms during the SW-IOP '97 are still being 
investigated.

null
This data set has been archived as sgprcfbbswiop97C1.00

• Downwelling Shortwave Diffuse Hemispheric Irradiance, Pyrgeometer, Minima(down_short_diffuse_hemisp_min)
• Downwelling shortwave hemispheric irradiance, pyranometer, maxima(down_short_hemisp_max)
• Downwelling longwave hemispheric irradiance, pyrgeometer(down_long_hemisp)
• Upwelling (10 meter) Shortwave Hemispheric Irradiance, Pyranometer, Maxima(up_short_hemisp_max)
• Upwelling Longwave Hemispheric Irradiance, Pyrgeometer, Minima(up_long_hemisp_min)
• Downwelling Shortwave Diffuse Hemispheric Irradiance, Ventilated Pyranometer(down_short_diffuse_hemisp)
• Shortwave Direct Normal Irradiance, Pyrgeometer, Standard Deviation(short_direct_normal_std)
• Upwelling (10 meter) Longwave Hemispheric Irradiance, Ventilated Pyrgeometer,
  Standard Deviation(up_long_hemisp_std)
• Downwelling Longwave Hemispheric Irradiance, Pyrgeometer, Maxima(down_long_hemisp_max)
• 10 meter Upwelling Longwave Hemispheric Irradiance, Pyrgeometer(up_long_hemisp)
• Downwelling Shortwave Diffuse Hemispheric Irradiance, Pyranometer, Standard
  Deviation(down_short_diffuse_hemisp_std)
• Upwelling shortwave hemispheric irradiance, pyranometer, minima(up_short_hemisp_min)
• Downwelling Longwave Hemispheric Irradiance, Pyrgeometer, Minima(down_long_hemisp_min)
• Downwelling Shortwave Hemispheric Irradiance, Ventilated Pyrgeometer, Standard
  Deviation(down_short_hemisp_std)
• Upwelling (10 meter) Shortwave Hemispheric Irradiance, Ventilated Pyranometer,
  Standard Deviation(up_short_hemisp_std)
• Shortwave direct normal irradiance, pyrheliometer(short_direct_normal)
• Shortwave direct normal irradiance, pyrheliometer, minima(short_direct_normal_min)
• Down-welling unshaded pyranometer voltage(down_short_hemisp)
• Shortwave Direct Normal Irradiance, Pyrheliometer, Maxima(short_direct_normal_max)
• Downwelling Longwave Hemispheric Irradiance, Ventilated Pyrgeometer, Standard
  Deviation(down_long_hemisp_std)
• Upwelling longwave hemispheric irradiance, pyrgeometer, maxima(up_long_hemisp_max)
• 25 meter Upwelling Shortwave Hemispheric Irradiance, Pyranometer(up_short_hemisp)
• Downwelling Shortwave Hemispheric Irradiance, Pyranometer, Minima(down_short_hemisp_min)
• Downwelling shortwave diffuse hemispheric irradiance, pyranometer, maxima(down_short_diffuse_hemisp_max)

• Hemispheric Irradiance, MFRSR(hemisp_narrowband)
• Downwelling Longwave Diffuse Hemispheric Irradiance, Ventilated Pyrgeometer(down_long_diffuse_hemisp)
• 25 meter Upwelling Shortwave Hemispheric Irradiance, Pyranometer(up_short_hemisp)
• Ventilated Pyrgeometer Case Temperature(down_long_case_temp)
• Downwelling Shortwave Diffuse Hemispheric Irradiance, Ventilated Pyranometer(down_short_diffuse_hemisp)
• Diffuse Hemispheric Broadband Irradiance, offset corrected(diffuse_hemisp_broadband)
• Shortwave direct normal irradiance, pyrheliometer(short_direct_normal)
• Ventilated Pyrgeometer Dome Temperature(down_long_dome_temp)
• Hemispheric broadband irradiance(hemisp_broadband)
• Direct Normal Irradiance, NIMFR(direct_norm_narrowband)
• 10 meter Upwelling Longwave Hemispheric Irradiance, Pyrgeometer(up_long_hemisp)
• Direct Normal Irradiance, MFRSR(direct_norm_broadband)
• Down-welling unshaded pyranometer voltage(down_short_hemisp)
• Diffuse Hemispheric Irradiance, MFRSR(diffuse_hemisp_narrowband)

• (Raw data stream - documentation not supported)

• Downwelling longwave hemispheric irradiance, pyrgeometer(down_long_hemisp)
• Down-welling unshaded pyranometer voltage(down_short_hemisp)
• 25 meter Upwelling Shortwave Hemispheric Irradiance, Pyranometer(up_short_hemisp)
• Shaded pyranometer voltage(short_diffuse)
• 10 meter Upwelling Longwave Hemispheric Irradiance, Pyrgeometer(up_long_hemisp)

• Standard deviation for shaded pyranometer(spsp1)
• Standard deviation for unshaded pyranometer(spsp2)
• Direct-beam normal solar irradiance(nip)
• Standard deviation for pyrheliometer(snip)
• Average pyrgeometer thermopile voltage(psig)
• Standard deviation for pyrgeometer thermopile(ssig)
• Average shaded pyranometer voltage(psp1)

• Average pyrgeometer thermopile voltage(psig)
• Average unshaded pyranometer voltage(psp2)
• Average shaded pyranometer voltage(psp1)
• Direct-beam normal solar irradiance(nip)

• (Raw data stream - documentation not supported)