Data Quality Reports for Session: 144703 User: kobekim Completed: 09/10/2012


TABLE OF CONTENTS

DQR IDSubjectData Streams Affected
D010907.4 "bsrn" platform at SGP data problemsgpbsrnC1.00, sgpbsrnC1.a0, sgpbsrnC1.a1, sgpbsrn1duttC1.c1
D050420.2SGP/BSRN/C1 - Reprocess: Adjust Direct Normal IrradiancesgpbsrnC1.00, sgpbsrnC1.a0, sgpbsrnC1.a1
D940728.1BSRN Pyran(PSP1) shadearm off alignment and NIP not trackingsgpbsrnC1.a1
D950802.2bad radiation datasgpbsrnC1.a1
D970317.1downwelling solar irradiance measurement adjustmentssgpbsrnC1.a1, sgpsirosE13.a1
D971224.1SGP/BSRN/C1 - 12-hr file of 1993 BSRN data corruptedsgpbsrnC1.a0, sgpbsrnC1.a1
D980224.1Reference Broadband Shortwave Data at SGP Central Cluster during Fall IOP '97sgpbsrnC1.a0, sgpbsrnC1.a1, sgpsirosE13.a1, sgpbsrnC1.00, sgpsirosE13.00, sgpsirsE13.a0,
sgpsirsE13.a1


DQRID : D010907.4
Start DateStart TimeEnd DateEnd Time
10/01/1998000001/22/20012359
Subject:
"bsrn" platform at SGP data problem
DataStreams:sgpbsrnC1.00, sgpbsrnC1.a0, sgpbsrnC1.a1, sgpbsrn1duttC1.c1
Description:
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.
Measurements:sgpbsrnC1.00:
  • Raw data stream - documentation not supported

sgpbsrnC1.a1:
  • Calculated downwelling hemispheric diffuse solar irradiance(psp1)
  • psp2
  • Observed direct-beam normal solar irradiance(nip)
  • Downwelling hemispheric infrared irradiance(psig)

sgpbsrnC1.a0:
  • snip
  • ssig
  • vbat
  • Observed direct-beam normal solar irradiance(nip)
  • psp2
  • Calculated downwelling hemispheric diffuse solar irradiance(psp1)
  • spsp2
  • stdome
  • spsp1
  • vref
  • stcase
  • ptcase
  • ptdome
  • Downwelling hemispheric infrared irradiance(psig)
  • svref

sgpbsrn1duttC1.c1:
  • 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
  • dsdh_full_corrected
  • Downwelling Shortwave Hemispheric Irradiance, Ventilated Pyranometer, Minima(down_short_hemisp_min)
  • case_temperature
  • down_short_hemisp_std
  • down_short_diffuse_hemisp_std
  • Irradiance, longwave, downwelling, hemispheric(down_long_hemisp)


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DQRID : D050420.2
Start DateStart TimeEnd DateEnd Time
07/28/2000143001/22/20011739
Subject:
SGP/BSRN/C1 - Reprocess: Adjust Direct Normal Irradiance
DataStreams:sgpbsrnC1.00, sgpbsrnC1.a0, sgpbsrnC1.a1
Description:
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.
Measurements:sgpbsrnC1.00:
  • Raw data stream - documentation not supported

sgpbsrnC1.a1:
  • Observed direct-beam normal solar irradiance(nip)

sgpbsrnC1.a0:
  • Observed direct-beam normal solar irradiance(nip)


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DQRID : D940728.1
Start DateStart TimeEnd DateEnd Time
07/15/1994000007/19/19942359
Subject:
BSRN Pyran(PSP1) shadearm off alignment and NIP not tracking
DataStreams:sgpbsrnC1.a1
Description:
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:



-----------------------------------------------------------------
END
Measurements:sgpbsrnC1.a1:
  • Downwelling hemispheric infrared irradiance(psig)
  • lat
  • lon
  • time_offset
  • Calculated downwelling hemispheric diffuse solar irradiance(psp1)
  • psp2
  • base_time
  • alt
  • Observed direct-beam normal solar irradiance(nip)


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DQRID : D950802.2
Start DateStart TimeEnd DateEnd Time
07/16/1995183607/17/19952359
Subject:
bad radiation data
DataStreams:sgpbsrnC1.a1
Description:
DQR No:                               Platform:  SGP BSRN C1.A1
                                                 (surface radiation station)

Subject:  Bad radiation data on July 17

Date Submitted:  July 7, 1995
Submitted By:  John Augustine         _X_  Instrument Mentor
               for John Deluisi       ___  EST Member
                                      ___  Science Team Member
                                      ___  Other 
_____________________________
 
For questions or problems, please contact the ARM Experiment 
Center at
509-375-6898 or via email at dqr@arm.gov.

Platform/Measurement:
    What level data: (raw,a0,a1,b1,c1 etc):  a1

    What location was the data collected at:  SGP
 
    Period of time in question
        Begin Date   7/16/95   Time   18:36    (GMT)  
        End Date     7/17/95   Time   23:59    (GMT)

 Data should be labeled:
 ___  questionable             ___  All data fields affected
 ___  incorrect                _X_ Only some data fields affected
 ___  wrong calibration
 ___  others 
 
 Discussion of Problem:

After looking at the plots for solar direct, diffuse, and global 
radiation, I believe that two problems are evident.  The data on July 16
look normal for quasi-clear sky conditions until about 18:36 (UTC).  The
rest of the day looks cloudy, i.e., the global and diffuse follow each
other, and the NIP signal is near 0, although noisy (i.e., the NIP signal
actually goes below 0 w m^-2 for two short periods between 2000 and 2100
UTC).

The diffuse and NIP data on July 17 are suspect.  The NIP reads zero all
day.  From sunrise to 17:55 (UTC), the diffuse and global track each
other to fairly high values (max 1000 W m^2).  After the fuse was
replaced, at 17:55, the diffuse radiation drops to normal values (around
300 W m^2), and the global remains at high (normal) values.  This
suggests that the blown fuse affected the shade disk mechanism for the
diffuse radiometer.  However, the NIP remains at zero all day long.
According to the data on July 17, which suggests that it was a partly
cloudy day with no deep clouds, the NIP signal should be comparable to
the global reading.  Therefore the NIP's erroneous signal was not corrected
after the fuse was replaced.

On July 18, all solar data look good, suggesting that the problem with
the NIP was corrected sometime before sunrise.


Other observations/measurements impacted by this problem:



Suggested corrections of the Problem:  (e.g. change calibration
factor and recompute, flag data with this comment, etc.)

    Flag data according to the above discussion.  NIP and diffuse
    measurement affected.


Data Processing Notes                     Date
Measurements:sgpbsrnC1.a1:
  • Downwelling hemispheric infrared irradiance(psig)
  • lat
  • lon
  • time_offset
  • Calculated downwelling hemispheric diffuse solar irradiance(psp1)
  • psp2
  • base_time
  • alt
  • Observed direct-beam normal solar irradiance(nip)


Back To Table of Contents

DQRID : D970317.1
Start DateStart TimeEnd DateEnd Time
10/13/1995000008/20/19972359
Subject:
downwelling solar irradiance measurement adjustments
DataStreams:sgpbsrnC1.a1, sgpsirosE13.a1
Description:
A comparison of BSRN and SIROS solar radiometers for measuring downwelling 
irradiances at the SGP central facility was made with field standards and two 
absolute cavity radiometers brought to the site or a two-week period in April 
1996 by Mike Rubes (formerly of the National and Oceanic Atmospheric 
Administration, Air Resources Laboratory, Surface Radiation Research Branch in 
Boulder, CO).  A description of this effort can currently be found on the 
World Wide Web at http://www.srrb.noaa.gov/apr96iop/hagsie.html.  Analyses of 
the data from these comparisons have resulted in several observations on the 
quality of data collected at the BSRN and SIROS platforms since October 13, 
1995, which are probably valid to the present time, until these sensors are 
replaced with more recently calibrated sensors.  On Oct. 13, 1995, the two 
BSRN pyranometers (PSPs) were replaced, so the observations do not apply to 
the BSRN measurements of global and diffuse irradiation before that date.  
Another source of information is inspection of the SIROS and BSRN equipment by 
Joe Michalsky (Atmospheric Science Research Center, State University of New 
York at Albany) at various times.  The results of the findings are summarized 
as recommendations in the following several paragraphs.  Some explanation and 
further comments are provided in the parenthetical remarks.

ANALYSIS WHEN THE DIRECT BEAM WAS NOT OBSCURED BY CLOUDS

Direct-beam solar irradiance measured with the BSRN pyrheliometer (NIP) are 
too large by approximately 0.5% compared to the two absolute cavity 
radiometers.  (This small underestimate is within the expected level of 
uncertainty.)  

Direct-beam solar irradiance measured with the SIROS pyrheliometer are too 
small by approximately 2.1% compared to the two absolute cavity radiometers.  
(This large discrepancy is unexplained and will be explored during future 
calibration activities at the SGP Radiation Calibration Facility.)  

Possibly the best estimate of downwelling total hemispherical solar (global) 
irradiance can be made by summing the SIROS pyrheliometer irradiance reading 
multiplied by 1.021 (and by the cosine of the solar zenith angle) and the 
average of the readings for diffuse irradiance from the shaded BSRN and SIROS 
pyranometers.  The direct-beam part can alternatively be computed as 0.995 
times the BSRN pyrheliometer reading.  For data collected in October before 
the 13th, when the BSRN shaded pyrheliometer was replaced, the diffuse 
component is probably best computed directly from the SIROS shaded sensor 
alone.  

Downwelling total hemispherical solar (global) irradiance measured by the BSRN 
unshaded pyranometer is approximately 2% too small (which is within the 
expected level of uncertainty for unshaded pyranometer measurements) compared 
to the values computed from the measured direct-beam and diffuse components.  

(Downwelling total hemispherical solar irradiances measured by the SIROS 
unshaded pyranometer systematically underestimates the global irradiances 
by excessive amounts, i.e., by greater than 3%.)  

The analyses leading to these recommendations are described in an extended 
abstract presented in early February (J. Michalsky et al., "Optimal 
Measurements of Surface Shortwave Irradiance Using Current Instrumentation--
The ARM Experience," in Preprint Volume, Ninth Conference on Atmospheric 
Radiation, Feb. 2-7, Long Beach, California, pp. J5-J9, American 
Meteorological Society, Boston, MA).  Further relevant analyses were conducted 
by Kato et al., (Seiji Kato, Pennsylvania State University) and are described 
in a manuscript submitted for publication ("Uncertainties in Modelled and 
Measured Clear Sky Surface Shortwave Irradiances")." 

UNSHADED PYRANOMETER PERFORMANCE WHEN THE DIRECT BEAM WAS NOT OBSCURED

The above recommendations are based mostly on analyses conducted for 
cloudless, midday conditions.  Because the data reported from the unshaded 
pyranometer were not corrected for cosine response, slight overestimates of 
global irradiance from unshaded pyranometers tend to occur in cloudless 
conditions at solar zenith angles less than 45 deg and slight underestimates 
tend to occur for zenith angles greater than 55 deg.  The maximum deviations 
occur at extreme solar zenith angles and are about 2%.  

TRACKER-SHADING PERFORMANCE

The data user should note, as has been noted in data release statements, that 
analyses of the direct, diffuse, and/or direct beam irradiances should be 
preceded by a check of sensor performances by summing the direct and diffuse 
components and comparing the result to the directly measured global component.  
When this is done, problems with solar tracking are usually apparent.

Because slight misalignments in the tracking and shading devices can be 
difficult to detect, small deviations of the component sum from expected 
behavior are sometimes difficult to explain.  If such deviations tend to recur 
for specific time intervals for several days, one might suspect a tracking or 
shading problem.  For the time period addressed here, the modern tracking- 
shading assembly used with the SIROS sensors appeared to work well.  For the 
BSRN sensors until January 1996, an older tracking-shading system was used 
that was not as reliable as the modern assembly used with the SIROS sensors; 
problems with this BSRN tracking and shading system, were usually evident when 
they occurred.  A modern tracker-shader was installed for the BSRN sensors in 
January 1996. The tracker was not aligned as well as it could be.  Efforts are 
underway to improve tracker alignment checks and procedures at all SIROS sites 
and the BSRN site.  

PARTLY CLOUD CONDITIONS

An analysis by Chuck Long (formerly at the Pennsylvania State University and 
now with the University of Colorado and the National Oceanic and Atmospheric 
Administration) indicated that data users who are investigating partly cloudy 
sky conditions will usually find that the BSRN outputs are more reliable for 
short periods of time, say less than 30 min, than are the SIROS outputs.  This 
tends to occur because the SIROS data are recorded only every 20 s while the 
BSRN data represent one-minute averages computed on the basis of sampling once 
per second.  Under partly cloudy conditions, sampling only once every 20 s 
tends to provide inadequate statistical representation of downwelling 
irradiances.  

ESTIMATES FOR CLOUDY CONDITIONS

The component sum technique is not applicable for overcast conditions.  For 
the time period addressed here, the SIROS shaded sensor appears most reliable 
before October 13, 1995.  Thereafter, an average of data from the SIROS shaded 
pyranometer, the shaded BSRN sensor, and the shaded BSRN sensor multiplied by 
1.02 might be the best estimate of global irradiance for cloudy conditions.  
However, a rigorous analysis on the results of this procedure has not been 
carried out, so the data user should approach this technique with caution.  

SOME ADDITIONAL INFORMATION

The excessively large deviations noted above for the pyranometers result in 
part from a mixture of different sources of calibration procedures.   The 
following table lists the sources of calibration:

Sensor       Coefficient used    Calibration     Installation
              to process data     date            date
BSRN PSP DS     BORCAL           Sept. 1995      Oct. 13, 1995
BSRN PSP DD     Eppley           June 1995       Oct. 13, 1995
BSRN NIP        BORCAL           July 1993       March 17, 1994
SIROS PSP DS    Eppley           June 1995       July 25, 1995
SIROS PSP DD    Eppley           June 1995       July 25, 1995
SIROS NIP       BORCAL           Sept. 1994      July 25, 1995

DS =  downwelling solar or global
DD =  downwelling diffuse
PSP = precision spectral pyranometer
NIP = normal incidence pyrheliometer for direct-beam solar
BORCAL = broadband outdoor radiometer calibration, conducted by the National 
         Renewable Energy Laboratory (NREL)
Eppley = denotes calibrations in an integrating sphere by the manufacturer,
         Eppley Laboratory, Inc.

The BORCAL calibrations result in estimates of solar irradiances that are 
typically 1.5% larger than Eppley calibrations, a situation which is under 
investigation by Tom Stoffel at NREL and John Hickey at Eppley.  They are 
working together to document this difference.  This difference helps to 
explain the larger estimates of global irradiance measurement with the BSRN 
sensor than with the SIROS sensor.  

A greater source of concern than over differences between the NREL versus the 
Eppley calibrations at this time is the insufficiently frequent recalibrations 
of sensors in operation at the SGP site.  Although the NIPs are expected to 
hold their calibrations for rather long periods of time, the pyranometers 
typically should be recalibrated at least once every 12 months.  Change out 
with freshly calibrated pyranometers and pyrheliometers at the SGP site will 
begin in 1997, with the goal of routinely replacing every pyranometer and 
pyrheliometer with freshly calibrated sensors once every year.  

Data users can inspect metrics provided on the World Wide Web by the SGP site 
scientist team on data quality at the following address:
http://manatee.gcn.uoknor.edu/metrics/METRICS.html

Other observations/measurements impacted by this problem:

Any derived estimates of downwelling solar radiation components using data 
from central facility SIROS or BSRN sensors (for downwelling solar radiation) 
for the time period indicated.

Suggested Corrections of the Problem: (e.g. change calibration factor and 
recompute, flag data with this comment, etc.)

Use of these recommendations by data users.  Ideally, the component sum 
technique would be applied in a value-added product (VAP) implemented at the 
Experiment Center, but this has not been done yet.  In the meantime, users of 
recent data can inspect plots of component sum technique on the World Wide Web 
site noted above.
Measurements:sgpsirosE13.a1:
  • logger_volt
  • Radiation, longwave, at 10-m height, upwelling hemispheric irrad., 1-min avg(up_long_hemisp)
  • down_long_diffuse_hemisp
  • flag_zero_cosine1-24
  • down_long_case_temp
  • up_long_dome_temp
  • lat
  • base_time
  • up_long_case_temp
  • mfrsr_temp
  • therm_volt
  • logger_temp
  • down_long_dome_temp
  • alt
  • Direct Normal Irradiance, NIMFR(direct_norm_narrowband)
  • flag_nighttime1-24
  • Direct Normal Broadband Irradiance(direct_norm_broadband)
  • hemisp_broadband
  • flag_ln_error1-24
  • channel
  • flag_zero_divisor1-24
  • diffuse_hemisp_broadband
  • hemisp_narrowband
  • lon
  • Radiation, shortwave, at 10-m height, upwelling hemispheric irrad., 1-min avg(up_short_hemisp)
  • Radiation, shortwave, direct normal irradiance, 1-min avg(short_direct_normal)
  • diffuse_hemisp_narrowband
  • Radiation, shortwave, downwelling diffuse hemispheric irradiance, 1-min avg(down_short_diffuse_hemisp)
  • time_offset
  • Radiation, shortwave, downwelling total hemispheric irradiance, 1-min avg(down_short_hemisp)

sgpbsrnC1.a1:
  • Calculated downwelling hemispheric diffuse solar irradiance(psp1)
  • psp2
  • time_offset
  • Observed direct-beam normal solar irradiance(nip)
  • lat
  • base_time
  • alt
  • Downwelling hemispheric infrared irradiance(psig)
  • lon


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DQRID : D971224.1
Start DateStart TimeEnd DateEnd Time
07/21/1993023407/21/19930235
Subject:
SGP/BSRN/C1 - 12-hr file of 1993 BSRN data corrupted
DataStreams:sgpbsrnC1.a0, sgpbsrnC1.a1
Description:
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.
Measurements:sgpbsrnC1.a1:
  • Calculated downwelling hemispheric diffuse solar irradiance(psp1)
  • psp2
  • time_offset
  • Observed direct-beam normal solar irradiance(nip)
  • lat
  • base_time
  • alt
  • Downwelling hemispheric infrared irradiance(psig)
  • lon

sgpbsrnC1.a0:
  • base_time
  • snip
  • alt
  • ssig
  • vbat
  • Observed direct-beam normal solar irradiance(nip)
  • psp2
  • Calculated downwelling hemispheric diffuse solar irradiance(psp1)
  • spsp2
  • spsp1
  • stdome
  • lat
  • vref
  • lon
  • stcase
  • ptcase
  • time_offset
  • ptdome
  • Downwelling hemispheric infrared irradiance(psig)
  • svref


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DQRID : D980224.1
Start DateStart TimeEnd DateEnd Time
09/17/1997000010/03/19972359
Subject:
Reference Broadband Shortwave Data at SGP Central Cluster during Fall IOP '97
DataStreams:sgpbsrnC1.a0, sgpbsrnC1.a1, sgpsirosE13.a1, sgpbsrnC1.00, sgpsirosE13.00, sgpsirsE13.a0,
sgpsirsE13.a1
Description:
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.
Measurements:sgpsirosE13.a1:
  • down_long_diffuse_hemisp
  • Direct Normal Broadband Irradiance(direct_norm_broadband)
  • Radiation, shortwave, downwelling diffuse hemispheric irradiance, 1-min avg(down_short_diffuse_hemisp)
  • Radiation, longwave, at 10-m height, upwelling hemispheric irrad., 1-min avg(up_long_hemisp)
  • down_long_case_temp
  • down_long_dome_temp
  • Direct Normal Irradiance, NIMFR(direct_norm_narrowband)
  • hemisp_broadband
  • diffuse_hemisp_broadband
  • hemisp_narrowband
  • Radiation, shortwave, at 10-m height, upwelling hemispheric irrad., 1-min avg(up_short_hemisp)
  • Radiation, shortwave, direct normal irradiance, 1-min avg(short_direct_normal)
  • diffuse_hemisp_narrowband
  • Radiation, shortwave, downwelling total hemispheric irradiance, 1-min avg(down_short_hemisp)

sgpbsrnC1.00:
  • Raw data stream - documentation not supported

sgpbsrnC1.a1:
  • Observed direct-beam normal solar irradiance(nip)
  • Downwelling hemispheric infrared irradiance(psig)
  • Calculated downwelling hemispheric diffuse solar irradiance(psp1)
  • psp2

sgpbsrnC1.a0:
  • spsp2
  • spsp1
  • snip
  • ssig
  • Observed direct-beam normal solar irradiance(nip)
  • Calculated downwelling hemispheric diffuse solar irradiance(psp1)
  • Downwelling hemispheric infrared irradiance(psig)

sgpsirosE13.00:
  • Raw data stream - documentation not supported

sgpsirsE13.a0:
  • Radiation, shortwave, downwelling total hemispheric irradiance, 1-min avg(down_short_hemisp)
  • Radiation, shortwave, at 10-m height, upwelling hemispheric irrad., 1-min avg(up_short_hemisp)
  • short_diffuse
  • Irradiance, longwave, downwelling, hemispheric(down_long_hemisp)
  • Radiation, longwave, at 10-m height, upwelling hemispheric irrad., 1-min avg(up_long_hemisp)

sgpsirsE13.a1:
  • up_long_hemisp_std
  • down_short_diffuse_hemisp_std
  • Radiation, longwave, at 10-m height, upwelling hemispheric irrad., 1-min avg(up_long_hemisp)
  • Downwelling Shortwave Hemispheric Irradiance, Ventilated Pyranometer, Minima(down_short_hemisp_min)
  • Radiation, shortwave, downwelling total hemispheric irradiance, 1-min avg(down_short_hemisp)
  • Irradiance, longwave, downwelling, hemispheric(down_long_hemisp)
  • Radiation, shortwave, downwelling diffuse hemispheric irradiance, 1-min avg(down_short_diffuse_hemisp)
  • short_direct_normal_std
  • Upwelling Longwave Hemispheric Irradiance, Unventilated Pyrgeometer, Maxima(up_long_hemisp_max)
  • Downwelling Shortwave Diffuse Hemisp. Irrad., Ventilated Pyranometer, Maxima(down_short_diffuse_hemisp_max)
  • down_long_hemisp_std
  • Shortwave Direct Normal Irradiance, Pyrheliometer, Maxima(short_direct_normal_max)
  • up_short_hemisp_std
  • Upwelling Longwave Hemispheric Irradiance, Unventilated Pyrgeometer, Minima(up_long_hemisp_min)
  • Upwelling Shortwave Hemispheric Irradiance, Unventilated Pyranometer, Minima(up_short_hemisp_min)
  • Radiation, shortwave, direct normal irradiance, 1-min avg(short_direct_normal)
  • Downwelling Shortwave Diffuse Hemisp. Irrad., Ventilated Pyranometer, Minima(down_short_diffuse_hemisp_min)
  • Downwelling Shortwave Hemispheric Irradiance, Ventilated Pyranometer, Maxima(down_short_hemisp_max)
  • Shortwave Direct Normal Irradiance, Pyrheliometer, Minima(short_direct_normal_min)
  • down_long_hemisp_max
  • down_long_hemisp_min
  • Radiation, shortwave, at 10-m height, upwelling hemispheric irrad., 1-min avg(up_short_hemisp)
  • Upwelling Shortwave Hemispheric Irradiance, Unventilated Pyranometer, Maxima(up_short_hemisp_max)
  • down_short_hemisp_std


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