ONgoing Data Quality Problems

(NOTE: THIS DQR REPLACES P960327.1 SUBMITTED EARLIER)
----------------------------------------------------
Date Submitted: 1 April 1996
Submitted By: Jim Barnard             _X_  Instrument Mentor
                                      ___  EST Member
                                      ___  Science Team Member
                                      ___  Other _____________________________
 
For questions or problems, please contact the ARM Experiment Center at
509-375-6898 or via email at problems@arm.gov.

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

    What location was the data collected at: 
 
    Period of time in question
        Begin Date   96/03/07  Time   00:00    (GMT)
        End Date     96/03/21  Time   21:30    (GMT)
        (For the NIP, some errors are occasionally observed
         after the "End Date"). 

 Data should be labeled:
 ___  questionable                      ___  All data fields affected
 _x_  incorrect                         _x_  Only some data fields affected
 ___  wrong calibration
 ___  others 
 
 Discussion of Problem: Data has been collected at site E2 since
about March 7, 1996. From this date to about March 21, 1996, the signal
from both IR pyrgeometers (both upwelling and downwelling) is bad. 
Additionally, the signal from the NIP and the upwelling SW sensor is
likewise bad.  After March 21, 1996 these instruments were repaired
although the status of the NIP is still unclear.  After this date, the NIP
has been observed to suddenly emit a signal that is far too high.  After a
few hours, the signal suddenly drops back to its proper value.  These 
excursions are rare, however the data user should be mindful of them.
 
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.)

• lon(lon)
• Ventilated Pyrgeometer Dome Temperature(down_long_dome_temp)
• Downwelling Longwave Diffuse Hemispheric Irradiance, Ventilated Pyrgeometer(down_long_diffuse_hemisp)
• Data Logger Temperature(logger_temp)
• Diffuse Hemispheric Irradiance, MFRSR(diffuse_hemisp_narrowband)
• Thermistor Excitation Voltage, Data Logger(therm_volt)
• Down-welling unshaded pyranometer voltage(down_short_hemisp)
• Ventilated Pyrgeometer Case Temperature(down_long_case_temp)
• Direct Normal Irradiance, MFRSR(direct_norm_broadband)
• 25 meter Longwave Case Temperature, Pyrgeometer(up_long_case_temp)
• 10 meter Longwave Dome Temperature, Pyrgeometer(up_long_dome_temp)
• Flag fields with *2 returned from callang(flag_ln_error1-24)
• Data logger supply voltage(logger_volt)
• base time in epoch(base_time)
• Direct Normal Irradiance, NIMFR(direct_norm_narrowband)
• Flag fields with *4 returned from callang(flag_nighttime1-24)
• Time offset from base_time(time_offset)
• MFRSR channels(channel)
• -180.0 - +180.0(alt)
• Flag fields with *3 returned from callang(flag_zero_cosine1-24)
• North Latitude(lat)
• Shortwave direct normal irradiance, pyrheliometer(short_direct_normal)
• Flag fields with *1 returned from callang(flag_zero_divisor1-24)
• Hemispheric broadband irradiance(hemisp_broadband)
• Downwelling Shortwave Diffuse Hemispheric Irradiance, Ventilated Pyranometer(down_short_diffuse_hemisp)
• 25 meter Upwelling Shortwave Hemispheric Irradiance, Pyranometer(up_short_hemisp)
• Diffuse Hemispheric Broadband Irradiance, offset corrected(diffuse_hemisp_broadband)
• 10 meter Upwelling Longwave Hemispheric Irradiance, Pyrgeometer(up_long_hemisp)
• MFRSR Detector Temperature(mfrsr_temp)
• Hemispheric Irradiance, MFRSR(hemisp_narrowband)