SGP/SIRS/E2 - Missing data due to Ice storm and clock problems

Data are missing due to power failures caused by an ice storm
and resulting system/instrument clock problems.

• Raw data stream - documentation not supported

SGP/SIRS/E2 - Ventilator Fan Failure

Measured downwelling shortwave data was very questionable, reporting 
nighttime values as low as -50 W/m^2, while differing from calculated 
downwelling shortwave by as much as 50 W/m^2 lower during the day. The 
first indication of a problem was around 10 UTC, 9/14, when measured 
DS values suddenly dropped below 10 W/m^2 for about a 2 hour period 
before sunrise, then were consistently lower than calculated DS by as 
much as 40 W/m^2 during the day.

The problem got progressively worse with time until the ventilator fan was
replace on 9/25.  Ventilator fan failure changed the fundamental
operating characteristics of this PSP and resulted in unpredictable biased
measurements which cannot be corrected without additional empirical
characterization of the radiometer in question.

• Raw data stream - documentation not supported

SGP/SIRS/E1/E2/E3/E5/E8 - Snow on Radiometers

A large discrepancy between the measured values of downwelling hemispheric shortwave 
radiation and the derived values occurred on 2/02 at the listed sites.  The difference is on 
the order of 200 Wm^(-2) at E2 and to a lesser extent at the other affected stations.  
This problem most likely resulted from a previous day or night snow/ice accumulation on 
the Direct(NIP), Downwelling Sortwave(PSP) and/or  Downwelling Diffuse(8-48) instruments.  
During the morning hours of 02/02, Approx 1300-2000GMT, snow/ice was covering one or more 
of these three instruments resulting in faulty readings and incorrect derived 
downwelling shortwave values as well.  Instrument readings indicate the problem resolved itself 
later in the day through normal meltoff.

• Raw data stream - documentation not supported

SGP/SIRS/E2 - Reprocessing Notice (RID 293)

See below for details of reprocessing that was completed on 20150929.  Original 
DQR category: 4 (Red, Incorrect).

-----------------------------------------------------------

During the pyrgeometer instrument (PIR) changout a datalogger program was loaded with 
incorrect calibration coefficients for the shortwave instruments.  The affected measurements 
were : downwelling diffuse (DD), upwelling shortwave(US), direct normal (NIP) and 
downwelling shortwave(DS)

Recalculate irradiances by determining original mV signal and reapplying the correct 
calibration coefficients.  For each one minute irradiance value perform the following 
calculations by instrument:
DD(corrected) = (DD/107.24)*118.11
US(corrected) = (US/113.19)*118.21
NIP(corrected)= (NIP/120.17)*119.08
DS(corrected) = (DS/118.46)*117.33

• Raw data stream - documentation not supported

SGP/SIRS/E2 - Tracker mis-alignment

The solar tracker was not working correctly at this site from 2/3/2005 to 2/5/2005 
2359GMT.  After this time tracker mounted instruments appear to have been responding correctly.  
There was no maintenance intervention that rectified the tracking problem. This has 
happened in the past with the SGP SciTec trackers.

• Raw data stream - documentation not supported

SGP/SIRS/E2 - Reprocessed: Incorrect DIR calibration coefficients

During the DIR/UIR instrument changeout on 2/10/2005 the new datalogger program contained 
incorrect calibration coefficients for the DIR instrument. The program was corrected on 
3/10/2005.

These data were reprocessed and archived in September 2006.

• Raw data stream - documentation not supported

SGP/SIRS/C1/E1/E10/E11/E12/E13/E15/E16/E18/E19/E2/E20/E21/E22/E24/E25/E27/E3/E4/E5/E6/E7/E8/E9 - Ice

Ice storms affected the SGP central and extended facilities starting Dec 10 0000GMT to 
mid/late December. Each facility was affected at various times and degrees dependant on 
elevation, latitude and whether power failed for short or extended periods of time.  By 
December 15th most ice had melted from the radiometers at all the faclities but power outages 
and tracker failures persisted at some stations.

• Raw data stream - documentation not supported