TWP/QCRAD/C1/C2/C3  - error in qc flags

In the qc_down_short_diffuse_hemisp field, QC failures from the test indicated by bit_13, 
"data failed tracker off test", were set incorrectly as bit_9, "GSW2SumSW (93 > SZA > 75 
and SumSW > 50; GSW/SumSW < 0.85 or GSW/SumSW > 1.15)".  Solar tracker failures are 
correctly indicated in the aqc_down_short_diffuse_hemisp field. 

In the qc_short_direct_normal field, QC failures from the test indicated by bit_10, "data 
failed tracker off test", were set incorrectly as bit_9, "GSW2SumSW (93 > SZA > 75 and 
SumSW > 50; GSW/ SumSW < 0.85 or GSW/SumSW > 1.15)".  Solar tracker failures are correctly 
indicated in the aqc_short_direct_normal field. 

This is a software problem in the VAP that impacts all dates for which a solar tracker 
failure occurred prior to 20100608 for each facility.  The 20020312 start date was chosen 
because the DQR system can not link multiple start/end date/times with multiple facilities 
within the same report.  As a result, the latest start date corresponding to C3 was 
chosen. The actual start dates for which this problem could have occurred for each facility 
are as follows:

C1:  19961010
C2:  19981029
C3:  20020312

Please note that if a solar tracker failure is not indicated by the 
aqc_down_short_diffuse_hemisp and/or aqc_short_direct_normal fields you can ignore this DQR.

• Radiation, shortwave, direct normal irradiance, 1-min avg(short_direct_normal)
• Radiation, shortwave, downwelling diffuse hemispheric irradiance, 1-min avg(down_short_diffuse_hemisp)

• Radiation, shortwave, direct normal irradiance, 1-min avg(short_direct_normal)
• Radiation, shortwave, downwelling diffuse hemispheric irradiance, 1-min avg(down_short_diffuse_hemisp)

• Radiation, shortwave, direct normal irradiance, 1-min avg(short_direct_normal)
• Radiation, shortwave, downwelling diffuse hemispheric irradiance, 1-min avg(down_short_diffuse_hemisp)

TWP/QCRAD/C2 - MFRSR installation period

The MFRSR was being installed during this time, with many changes. All data should be used 
with caution during this time. 

Described in instrument DQR D020613.4.

• MFRSR_diffuse_hemisp_broadband
• MFRSR_hemisp_broadband
• MFRSR_flag
• MFRSR_direct_normal_broadband

• MFRSR_direct_normal_broadband
• MFRSR_diffuse_hemisp_broadband
• MFRSR_flag
• MFRSR_hemisp_broadband

• MFRSR_diffuse_hemisp_broadband
• MFRSR_flag
• MFRSR_hemisp_broadband
• MFRSR_direct_normal_broadband

• MFRSR_direct_normal_broadband
• MFRSR_hemisp_broadband
• MFRSR_flag
• MFRSR_diffuse_hemisp_broadband

TWP/QCRAD/C2 - Reprocess: Incorrect calibration coefficients

Incorrect calibration coefficients were used for downwelling shortwave and longwave 
irradiance. 

The following calculation method should be applied to correct the data, 

For the downwelling shortwave(PSPG) (DS)
Old Calibration coefficient [W/m2\mV] =119.68
New Calibration Coefficient [W/m2\mV] =125.94
DS(new_value)[W/m2]=( DS(old_value)[W/m2]/ 119.68 [W/m2\mV] )* 125.94 [W/m2/mV]

For the longwave irradiance (PIRG):

If the .a0 and .b1 data set available the following procedure should be applied for the 
downwelling LW
1) Obtain the following variables from the 20s datastream for each one minute of the 
affected time range:
  inst_down_long_hemisp1_dome_resist (Rd)
  inst_down_long_ hemisp1_case_resist (Rc)
  inst_down_long_ hemisp1_tp (tpDIR_mV)
					 
2) Using the 20s tp voltage in mV convert to uV.
  tpDIR[uV] = inst_down_long_hemisp1_tp [mV]*1000[uV/mV]

3) For each 20s data entry, convert Rd and Rc to temperature
  Td =1/ (a0 + (a1*LN (Rd*1000) + (a2*LN (Rd*1000)^3)))
  Tc = 1/ (a0 + (a1*LN (Rc*1000) + (a2*LN (Rc*1000)^3)))
  Where a0 = 0.0010295 
	a1 = 0.0002391
	a2 = 0.0000001568

4) Apply for each 20s data entry: (correct k1=0.2755)
  WinDIR(W/m^2)= [0.2755*tpDIR] + Sigma*Tc^4 -4*Sigma*(Td^4 - Tc^4)
  Where, 
	WinDIR = Corrected down_long_hemisp1 (W/m^2)
	Sigma = 5.6704E-8 (Stefan-Boltzman Constant)

				      
5) Generate new 1 minute average from the three 20-second measurements

For the longwave irradiance (PIRD):

If the .a0 and .b1 data set available the following procedure should be applied for the 
downwelling LW
1) Obtain the following variables from the 20s datastream for each one minute of the 
affected time range:
  inst_down_long_hemisp2_dome_resist (Rd)
  inst_down_long_ hemisp2_case_resist (Rc)
  inst_down_long_ hemisp2_tp (tpDIR_mV)
					 
2) Using the 20s tp voltage in mV convert to uV.
  tpDIR[uV] = inst_down_long_hemisp2_tp [mV]*1000[uV/mV]

3) For each 20s data entry, convert Rd and Rc to temperature
  Td =1/ (a0 + (a1*LN (Rd*1000) + (a2*LN (Rd*1000)^3)))
  Tc = 1/ (a0 + (a1*LN (Rc*1000) + (a2*LN (Rc*1000)^3)))
  Where a0 = 0.0010295 
	a1 = 0.0002391
	a2 = 0.0000001568

4) Apply for each 20s data entry: (correct k1=0.2786)
  WinDIR(W/m^2)= [0.2786*tpDIR] + Sigma*Tc^4 -4*Sigma*(Td^4 - Tc^4)
  Where, 
	WinDIR = Corrected down_long_hemisp2(W/m^2)
	Sigma = 5.6704E-8 (Stefan-Boltzman Constant)

				      
5) Generate new 1 minute average from the three 20-second measurements

This issue was also described in instrument DQR D031007.3.

• Best Estimate Global Downwelling Shortwave Hemispheric Irradiance(BestEstimate_down_short_hemisp)
• Irradiance, longwave, downwelling, hemispheric(down_long_hemisp)
• Radiation, shortwave, downwelling total hemispheric irradiance, 1-min avg(down_short_hemisp)

• Irradiance, longwave, downwelling, hemispheric(down_long_hemisp)
• Radiation, shortwave, downwelling total hemispheric irradiance, 1-min avg(down_short_hemisp)
• Best Estimate Global Downwelling Shortwave Hemispheric Irradiance(BestEstimate_down_short_hemisp)

• Best Estimate Global Downwelling Shortwave Hemispheric Irradiance(BestEstimate_down_short_hemisp)
• Irradiance, longwave, downwelling, hemispheric(down_long_hemisp)

• Best Estimate Global Downwelling Shortwave Hemispheric Irradiance(BestEstimate_down_short_hemisp)
• Irradiance, longwave, downwelling, hemispheric(down_long_hemisp)

TWP/QCRAD/C2 - Air temperature noisy or bad

Air temperature is bad or noisy during this time. 

Air temperature data is needed for tests on LW up and LW down pyrgeometer case and dome 
temperatures, and tests on the irradiances from upwelling LW/SW and downwelling LW.

There were no instrument DQRs on this problem at the time this report was submitted.

• Irradiance, longwave, downwelling, hemispheric(down_long_hemisp)
• Radiation, shortwave, at 10-m height, upwelling hemispheric irrad., 1-min avg(up_short_hemisp)
• LWupTc
• LWupTd
• Radiation, longwave, at 10-m height, upwelling hemispheric irrad., 1-min avg(up_long_hemisp)
• LWdnTc
• LWdnTd
• Radiation, shortwave, downwelling diffuse hemispheric irradiance, 1-min avg(down_short_diffuse_hemisp)
• Temp_Air

• Radiation, shortwave, at 10-m height, upwelling hemispheric irrad., 1-min avg(up_short_hemisp)
• LWdnTd
• LWdnTc
• LWupTd
• Radiation, shortwave, downwelling diffuse hemispheric irradiance, 1-min avg(down_short_diffuse_hemisp)
• LWupTc
• Temp_Air
• Irradiance, longwave, downwelling, hemispheric(down_long_hemisp)

• LWupTc
• LWupTd
• Radiation, longwave, at 10-m height, upwelling hemispheric irrad., 1-min avg(up_long_hemisp)
• Irradiance, longwave, downwelling, hemispheric(down_long_hemisp)
• Radiation, shortwave, downwelling diffuse hemispheric irradiance, 1-min avg(down_short_diffuse_hemisp)
• Temp_Air
• LWdnTd
• LWdnTc
• Radiation, shortwave, at 10-m height, upwelling hemispheric irrad., 1-min avg(up_short_hemisp)

• LWdnTc
• LWdnTd
• Radiation, shortwave, downwelling diffuse hemispheric irradiance, 1-min avg(down_short_diffuse_hemisp)
• Temp_Air
• Irradiance, longwave, downwelling, hemispheric(down_long_hemisp)
• LWupTd
• LWupTc
• Radiation, longwave, at 10-m height, upwelling hemispheric irrad., 1-min avg(up_long_hemisp)
• Radiation, shortwave, at 10-m height, upwelling hemispheric irrad., 1-min avg(up_short_hemisp)

TWP/QCRAD/C2 - Case and dome temperatures noisy or bad

Upwelling and downwelling longwave case and dome temperatures are noisy or bad during this 
time. Not all corrections and tests can be applied to LW fluxes as a result.

No instrument DQRs exist describing this problem.

• Irradiance, longwave, downwelling, hemispheric(down_long_hemisp)
• LWupTc
• LWupTd
• Radiation, longwave, at 10-m height, upwelling hemispheric irrad., 1-min avg(up_long_hemisp)
• LWdnTc
• LWdnTd

• Irradiance, longwave, downwelling, hemispheric(down_long_hemisp)
• Radiation, longwave, at 10-m height, upwelling hemispheric irrad., 1-min avg(up_long_hemisp)
• LWdnTd
• LWdnTc
• LWupTd
• LWupTc

• LWupTc
• LWupTd
• Radiation, longwave, at 10-m height, upwelling hemispheric irrad., 1-min avg(up_long_hemisp)
• Irradiance, longwave, downwelling, hemispheric(down_long_hemisp)
• LWdnTd
• LWdnTc

• LWdnTc
• LWdnTd
• Radiation, longwave, at 10-m height, upwelling hemispheric irrad., 1-min avg(up_long_hemisp)
• Irradiance, longwave, downwelling, hemispheric(down_long_hemisp)
• LWupTd
• LWupTc

TWP/QCRAD/C2 - NIP cable bad

Shortwave direct normal irradiance data are missing or incorrect due to instrument cable 
failure. Described in instrument DQR D070206.1.

Note that fewer quality checks can be applied accurately to the BestEstimate data.

• Radiation, shortwave, direct normal irradiance, 1-min avg(short_direct_normal)

• Radiation, shortwave, direct normal irradiance, 1-min avg(short_direct_normal)

• Radiation, shortwave, direct normal irradiance, 1-min avg(short_direct_normal)

• Radiation, shortwave, direct normal irradiance, 1-min avg(short_direct_normal)

TWP/QCRAD/C2 - Tracker failure

Tracker appears to be out of alignment or inoperative during these times. The 
short_direct_normal (NIP) and down_short_diffuse_hemisp (8-48) data appear to be bad and not 
recoverable.

Several of these periods are documented in instrument DQRs:

D110831.1, D090328.1, D081222.3, D040107.1, D011207.1, D011019.8

• Best Estimate Global Downwelling Shortwave Hemispheric Irradiance(BestEstimate_down_short_hemisp)
• Radiation, shortwave, downwelling diffuse hemispheric irradiance, 1-min avg(down_short_diffuse_hemisp)
• Radiation, shortwave, direct normal irradiance, 1-min avg(short_direct_normal)

• Radiation, shortwave, direct normal irradiance, 1-min avg(short_direct_normal)
• Radiation, shortwave, downwelling diffuse hemispheric irradiance, 1-min avg(down_short_diffuse_hemisp)
• Best Estimate Global Downwelling Shortwave Hemispheric Irradiance(BestEstimate_down_short_hemisp)

• Best Estimate Global Downwelling Shortwave Hemispheric Irradiance(BestEstimate_down_short_hemisp)
• Radiation, shortwave, direct normal irradiance, 1-min avg(short_direct_normal)
• Radiation, shortwave, downwelling diffuse hemispheric irradiance, 1-min avg(down_short_diffuse_hemisp)

• Radiation, shortwave, direct normal irradiance, 1-min avg(short_direct_normal)
• Best Estimate Global Downwelling Shortwave Hemispheric Irradiance(BestEstimate_down_short_hemisp)
• Radiation, shortwave, downwelling diffuse hemispheric irradiance, 1-min avg(down_short_diffuse_hemisp)

TWP/QCRAD/C2 - upwelling radiometers inverted

During calibration check periods the gndrad instruments are inverted
to compare with the skyrad pir and psp.

Most periods described in instrument DQRs: 

D990909.1, D030224.1, D031007.4, D040929.2, D050926.6

Last two periods identified manually from data.

• Radiation, longwave, at 10-m height, upwelling hemispheric irrad., 1-min avg(up_long_hemisp)
• Radiation, shortwave, at 10-m height, upwelling hemispheric irrad., 1-min avg(up_short_hemisp)

• Radiation, shortwave, at 10-m height, upwelling hemispheric irrad., 1-min avg(up_short_hemisp)
• Radiation, longwave, at 10-m height, upwelling hemispheric irrad., 1-min avg(up_long_hemisp)

• Radiation, longwave, at 10-m height, upwelling hemispheric irrad., 1-min avg(up_long_hemisp)
• Radiation, shortwave, at 10-m height, upwelling hemispheric irrad., 1-min avg(up_short_hemisp)

• Radiation, longwave, at 10-m height, upwelling hemispheric irrad., 1-min avg(up_long_hemisp)
• Radiation, shortwave, at 10-m height, upwelling hemispheric irrad., 1-min avg(up_short_hemisp)