"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.

• null(Raw data stream - documentation not supported)

• CALCULATED downwelling hemispheric diffuse solar irradiance(psp1)
• Observed downwelling hemispheric total solar irradiance (direct+diffuse)(psp2)
• Pyrheliometer voltage(nip)
• Downwelling hemispheric infrared irradiance(psig)

• Standard deviation for pyrheliometer(snip)
• Standard deviation for pyrgeometer thermopile(ssig)
• Batter Voltage(vbat)
• Pyrheliometer voltage(nip)
• Observed downwelling hemispheric total solar irradiance (direct+diffuse)(psp2)
• CALCULATED downwelling hemispheric diffuse solar irradiance(psp1)
• Standard deviation for unshaded pyranometer(spsp2)
• Standard deviation for shaded pyranometer(spsp1)
• Standard deviation for pyrgeometer dome thermistor resistance(stdome)
• Average reference voltage(vref)
• Standard deviation for pyrgeometer case thermistor resistance(stcase)
• Average pyrgeometer case thermistor resistance(ptcase)
• Average pyrgeometer dome thermistor resistance(ptdome)
• Downwelling hemispheric infrared irradiance(psig)
• Standard deviation for reference(svref)

• Shortwave Direct Normal Irradiance, Pyrgeometer, Minima(short_direct_normal_min)
• Downwelling Shortwave Hemispheric Irradiance, Ventilated Pyrgeometer, Dutton
  corrected(dsdh_dutton_corrected)
• Shortwave Direct Normal Irradiance, Pyrgeometer, Maxima(short_direct_normal_max)
• Downwelling Longwave Hemispheric Irradiance, Ventilated Pyrgeometer, Standard
  Deviation(down_long_hemisp_std)
• Downwelling Longwave Hemispheric Irradiance, Ventilated Pyrgeometer, Maxima(down_long_hemisp_max)
• Ventilated Pyrgeometer Dome Temperature(dome_temperature)
• Shortwave Direct Normal Irradiance, Pyrgeometer(short_direct_normal)
• Downwelling Shortwave Diffuse Hemispheric Irradiance, Ventilated Pyranometer,
  Minima(down_short_diffuse_hemisp_min)
• Detector flux (Down-welling pyrgeometer thermopile voltage * PIR-DIR calib-coef)
  Calculated value from 20s data(detector_flux)
• Down-welling unshaded pyranometer voltage(down_short_hemisp)
• Calculated Downwelling Longwave Hemispheric Irradiance, Ventilated Pyrgeometer
  from 20s data(calculated_down_long_hemisp)
• Downwelling Shortwave Diffuse Hemispheric Irradiance, Ventilated Pyranometer(down_short_diffuse_hemisp)
• Shortwave Direct Normal Irradiance, Pyrgeometer, Standard Deviation(short_direct_normal_std)
• Effective temperature(effective_temperature)
• Downwelling Shortwave Diffuse Hemispheric Irradiance, Ventilated Pyranometer,
  Maxima(down_short_diffuse_hemisp_max)
• Downwelling Shortwave Hemispheric Irradiance, Ventilated Pyranometer, Maxima(down_short_hemisp_max)
• Downwelling Longwave Hemispheric Irradiance, Ventilated Pyrgeometer, Minima(down_long_hemisp_min)
• Downwelling Shortwave Hemispheric Irradiance, Ventilated Pyranometer, Minima(down_short_hemisp_min)
• Downwelling Shortwave Hemispheric Irradiance, Ventilated Pyrgeometer, Full
  corrected (Weighted Mean absolute deviation using Median)(dsdh_full_corrected)
• Ventilated Pyrgeometer Case Temperature(case_temperature)
• Downwelling Shortwave Hemispheric Irradiance, Ventilated Pyranometer, Standard
  Deviation(down_short_hemisp_std)
• Downwelling Shortwave Hemispheric Irradiance, Pyranometer, Standard Deviation(down_short_diffuse_hemisp_std)
• Down-welling pyrgeometer thermopile voltage(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.

• null(Raw data stream - documentation not supported)

• Pyrheliometer voltage(nip)

• Pyrheliometer voltage(nip)

BSRN Pyran(PSP1) shadearm off alignment and NIP not tracking

Subject: BSRN Data Release (July 15 - July 19, 1994) 

Name: Trevor Ley (SRRB\NOAA)   Instrument Mentor Dr. John DeLuisi

Email address: trevor@srrb.noaa.gov

Telephone: (303) 497-7315

Institution: SRRB\NOAA


Platform/Measurement: BSRN Pyranometer (PSP1) shadearm off
alignment and NIP not tracking.

        what level data: a1

 period of time in question
        start: July 15, 1994 at 00:00:00 (GMT)

        end:   July 19, 1994 at 23:59:59  (GMT)


 Data should be labeled:
        
      -Calculated Global irradiance could be labeled
       "incorrect".
     - NIP not tracking correctly
       
 Discussion of Problem:

  1. The shadearm on the Pyranometer (PSP1), calculating diffuse  
     irradiance, was off alignment (power outage).  
 
     Use this algorithm to pick out the times that the 
     shadearm is off of alignment.

          (PSP2-(NIP*cosine of zenith angle))/PSP1 < .90

   2. NIP tracker was down because of power outage.

Other observations/measurements impacted by this problem:

          * Calculated Global Irradiance and Diffuse Irradiance
          * Direct Normal Irradiance measurement is Wrong

Suggested Corrections of the Problem:  None

    


REQUIRED ACTIONS:

This report is informational no further action required

Experiment Center action required as follows:

     Supply with BSRN data release (July 15- July 19, 1994)


-------------------------------------------------------
TO BE FILLED IN UPON COMPLETION OF ACTION ABOVE:
 Action Taken:


Experiment Center:



Site Operations:



Archive:




EST:



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END

• Downwelling hemispheric infrared irradiance(psig)
• lat(lat)
• lon(lon)
• Time offset of tweaks from base_time(time_offset)
• CALCULATED downwelling hemispheric diffuse solar irradiance(psp1)
• Observed downwelling hemispheric total solar irradiance (direct+diffuse)(psp2)
• base time(base_time)
• Dummy altitude for Zeb(alt)
• Pyrheliometer voltage(nip)

SGP/BSRN/C1 - 12-hr file of 1993 BSRN data corrupted

EDITOR'S NOTE:  The data referenced in this Data Quality Report
were collected and archived prior to the regular begin date of
ARM data.  These data are available for retrieval by special
request only.  The actual time range to which this DQR applies
is 930510.1511-930510.1611.

Because of power problems and the necessity to reset the power to the
shadow arms, data were lost. The data were not reingested to overcome 
this deficiency, and the 12-hr file bsrn1.930510.1200.cdf has a 59-min 
gap from 15:11 to 16:11.

• CALCULATED downwelling hemispheric diffuse solar irradiance(psp1)
• Observed downwelling hemispheric total solar irradiance (direct+diffuse)(psp2)
• Time offset of tweaks from base_time(time_offset)
• Pyrheliometer voltage(nip)
• lat(lat)
• base time(base_time)
• Dummy altitude for Zeb(alt)
• Downwelling hemispheric infrared irradiance(psig)
• lon(lon)

• base time(base_time)
• Standard deviation for pyrheliometer(snip)
• Dummy altitude for Zeb(alt)
• Standard deviation for pyrgeometer thermopile(ssig)
• Batter Voltage(vbat)
• Pyrheliometer voltage(nip)
• Observed downwelling hemispheric total solar irradiance (direct+diffuse)(psp2)
• CALCULATED downwelling hemispheric diffuse solar irradiance(psp1)
• Standard deviation for unshaded pyranometer(spsp2)
• Standard deviation for shaded pyranometer(spsp1)
• Standard deviation for pyrgeometer dome thermistor resistance(stdome)
• lat(lat)
• Average reference voltage(vref)
• lon(lon)
• Standard deviation for pyrgeometer case thermistor resistance(stcase)
• Average pyrgeometer case thermistor resistance(ptcase)
• Time offset of tweaks from base_time(time_offset)
• Average pyrgeometer dome thermistor resistance(ptdome)
• Downwelling hemispheric infrared irradiance(psig)
• Standard deviation for reference(svref)