"bsrn" platform at SGP data problem

As reported in ARM Technical Report ARM-TR-002, the 'bsrn' data at the SGP CF
was not in agreement with the co-located SIRS E13 and C1 data. Subsequent
discussion led to the conclusion that ther was a voltage problem with the
'bsrn' data logger. In development and testing of the Diffuse Correction and
Best Estimate Flux VAPs, it has been shown that all 'bsrn' data, all
instruments, suffered this data logger problem. The result is noisy and
slightly offset values, seemingly at random throughout the period from October
1998 through the end of the 'bsrn' data stream and it's replacement by the BRS
system. All this data needs to be colored 'questionable', and all data users
need to be informed that either the SIRS E13 or SIRS C1 data should be used
instead.

• Raw data stream - documentation not supported

• Calculated downwelling hemispheric diffuse solar irradiance(psp1)
• psp2
• Observed direct-beam normal solar irradiance(nip)
• Downwelling hemispheric infrared irradiance(psig)

• snip
• ssig
• vbat
• Observed direct-beam normal solar irradiance(nip)
• psp2
• Calculated downwelling hemispheric diffuse solar irradiance(psp1)
• spsp2
• spsp1
• stdome
• vref
• stcase
• ptcase
• ptdome
• Downwelling hemispheric infrared irradiance(psig)
• svref

• Shortwave Direct Normal Irradiance, Pyrheliometer, Minima(short_direct_normal_min)
• dsdh_dutton_corrected
• Shortwave Direct Normal Irradiance, Pyrheliometer, Maxima(short_direct_normal_max)
• down_long_hemisp_std
• down_long_hemisp_max
• dome_temperature
• Radiation, shortwave, direct normal irradiance, 1-min avg(short_direct_normal)
• Downwelling Shortwave Diffuse Hemisp. Irrad., Ventilated Pyranometer, Minima(down_short_diffuse_hemisp_min)
• detector_flux
• Radiation, shortwave, downwelling total hemispheric irradiance, 1-min avg(down_short_hemisp)
• calculated_down_long_hemisp
• Radiation, shortwave, downwelling diffuse hemispheric irradiance, 1-min avg(down_short_diffuse_hemisp)
• short_direct_normal_std
• effective_temperature
• Downwelling Shortwave Diffuse Hemisp. Irrad., Ventilated Pyranometer, Maxima(down_short_diffuse_hemisp_max)
• Downwelling Shortwave Hemispheric Irradiance, Ventilated Pyranometer, Maxima(down_short_hemisp_max)
• down_long_hemisp_min
• Downwelling Shortwave Hemispheric Irradiance, Ventilated Pyranometer, Minima(down_short_hemisp_min)
• dsdh_full_corrected
• case_temperature
• down_short_hemisp_std
• down_short_diffuse_hemisp_std
• Irradiance, longwave, downwelling, hemispheric(down_long_hemisp)

SGP/BSRN/C1 - Reprocess: Adjust Direct Normal Irradiance

Direct normal broadband shortwave irradiance measured by NIP s/n 30721E6 was found to have 
a 4.1% negative bias when compared in-situ with absolute cavity radiometer measurements 
taken on August 21, 2000.  The estimated measurement uncertainty of the calibration of 
NIP s/n 30721E6 on July 18, 2000 was -2.8% to +3.5%.  The additional uncertainties of the 
field (rather than calibration) data acquisition system and installation contribute to the 
large negative bias found in the data on August 21, 2000.

Data from NIP s/n 30721E6 can be adjusted according to the in-situ comparisons to reduce 
the apparent measurement bias.

• Raw data stream - documentation not supported

• Observed direct-beam normal solar irradiance(nip)

• Observed direct-beam normal solar irradiance(nip)