TWP/SKYRAD/C3 - Reprocess: PIR identified as unshaded is really shaded

From the initial installation of the Darwin SKYRAD suite of instruments, two shaded PIRs 
were installed rather than one shaded and one unshaded PIR as 
documented in the netcdf header information.

• Instantaneous Downwelling Pyrgeometer Dome Thermistor Temperature, Pyrgeometer2(inst_down_long_hemisp2_dome_temp)
• Downwelling Longwave Hemispheric Irradiance, Pyrgeometer2, Minima(down_long_hemisp2_min)
• Downwelling Longwave Hemispheric Irradiance, Pyrgeometer2, Maxima(down_long_hemisp2_max)
• Downwelling Longwave Hemispheric Irradiance, Pyrgeometer2, Standard Deviation(down_long_hemisp2_std)
• Instantaneous Downwelling Pyrgeometer Thermopile, Pyrgeometer2(inst_down_long_hemisp2_tp)
• Instantaneous Downwelling Pyrgeometer Case Thermistor Temperature, Pyrgeometer2(inst_down_long_hemisp2_case_temp)
• Downwelling Longwave Hemispheric Irradiance, Pyrgeometer2(down_long_hemisp2)

TWP/SKYRAD/C3  - IRT incorrect min/delta values

For field sky_ir_temp, the value of valid_min was incorrectly assigned to -49.7 C and no 
value of valid_delta was assigned. The actual values should be -60 and 50 C, respectively.

• Sky Infra Red Temperature Minima(sky_ir_temp_min)
• Sky Infra-Red Temperature(sky_ir_temp)
• Sky Infra Red Temperature Maxima(sky_ir_temp_max)

TWP/GNDRAD/C3 - IRT bias

The IRT behaved erratically, jumping frequently from reporting about 50 Wm^(-2) higher 
than the PIR for surface irradiance values to about 100Wm^(-2) lower than the PIR.  
Generally, the IRT measured lower surface temperatures than expected from the PIR.

• Surface Infra-Red Temperature, Standard Deviation(sfc_ir_temp_std)
• Surface Infra-Red Temperature Minima(sfc_ir_temp_min)
• Effective Surface (Skin) Temperature(sfc_ir_temp)
• Surface Infra-Red Temperature Maxima(sfc_ir_temp_max)

TWP/SKYRAD/C3 - Incorrect NIP cal coefficient

During our site visit comparison at Darwin we observed that the skyrad NIP was reading 
about 50 w/m2 lower than the comparison cavity radfiometer and the replacement NIP on the 
comparison stand. We found that the calibration coefficient for the NIP (responsivity at 
45o)was put in as 8.64X10-6. The NIP was new and had not been calibrated at SGP. The 
factory number was 8.04X10-6. We corrected the calibration coefficient and the instruments 
agreed to better than 5 w/m2.

• Shortwave Direct Normal Irradiance, Pyrgeometer, Minima(short_direct_normal_min)
• Shortwave Direct Normal Irradiance, Pyrgeometer(short_direct_normal)
• Shortwave Direct Normal Irradiance, Pyrgeometer, Maxima(short_direct_normal_max)
• Shortwave Direct Normal Irradiance, Pyrgeometer, Standard Deviation(short_direct_normal_std)

TWP/SKYRAD/C3 - Reprocess: NIP calibrations incorrect

On 05/20 during installtion of the new Campbell datalogger system and associated program 
the NIP (S/N 33551E6) was assigned an incorrect calibration coefficient.  A coefficient of 
116.01 W/m2/mV was applied when it should have been 124.378 W/m2/mV.
TWP reports SV0405D and SV0409D detail the activities which lead to this DQR.

• null(Raw data stream - documentation not supported)

• Shortwave Direct Normal Irradiance, Pyrgeometer, Minima(short_direct_normal_min)
• Shortwave Direct Normal Irradiance, Pyrgeometer(short_direct_normal)
• Shortwave Direct Normal Irradiance, Pyrgeometer, Maxima(short_direct_normal_max)
• Shortwave Direct Normal Irradiance, Pyrgeometer, Standard Deviation(short_direct_normal_std)

TWP/GNDRAD/C3 - IRT bias

The IRT measured higher surface temperatures than expected from the PIR, even at night.

• Surface Infra-Red Temperature Minima(sfc_ir_temp_min)
• Effective Surface (Skin) Temperature(sfc_ir_temp)
• Surface Infra-Red Temperature Maxima(sfc_ir_temp_max)

TWP/GNDRAD/C3 - Reprocess: IRT with wrong calibration

A spare IRT was installed that was not configured properly.

• Surface Infra-Red Temperature Minima(sfc_ir_temp_min)
• Effective Surface (Skin) Temperature(sfc_ir_temp)
• Surface Infra-Red Temperature Maxima(sfc_ir_temp_max)

TWP/GNDRAD/C3 - Tower inverted for instrument testing and replacement

The tower at Darwin was brought down to test and replace the Gndrad PIR on 8/5/2005 and 
the PSP on 8/9/2005

• Surface Infra-Red Temperature, Standard Deviation(sfc_ir_temp_std)
• Upwelling (10 meter) Shortwave Hemispheric Irradiance, Pyranometer, Standard
  Deviation(up_short_hemisp_std)
• Upwelling (10 meter) Shortwave Hemispheric Irradiance, Pyranometer(up_short_hemisp)
• Surface Infra-Red Temperature Minima(sfc_ir_temp_min)
• Effective Surface (Skin) Temperature(sfc_ir_temp)
• Upwelling (10 meter) Shortwave Hemispheric Irradiance, Pyranometer, Minima(up_short_hemisp_min)
• Upwelling (10 meter) Longwave Hemispheric Irradiance, Pyrgeometer, Maxima(up_long_hemisp_max)
• Upwelling (10 meter) Longwave Hemispheric Irradiance, Pyrgeometer, Minima(up_long_hemisp_min)
• Upwelling (10 meter) Shortwave Hemispheric Irradiance, Pyranometer, Maxima(up_short_hemisp_max)
• Upwelling (10 meter) Longwave Hemispheric Irradiance, Pyrgeometer, Standard
  Deviation(up_long_hemisp_std)
• Upwelling (10 meter) Longwave Hemispheric Irradiance, Pyrgeometer(up_long_hemisp)
• Surface Infra-Red Temperature Maxima(sfc_ir_temp_max)

TWP/SKYRAD/C3 - tracker inoperative

A lightning strike at Darwin removed the tracker from service.  Instruments installed on 
the tracker were rendered either inoperative or were not shaded during this time period.  
The longwave hemispheric instruments PIR1 and PIR2 appear to have been unaffected.  They 
are not suseptable to incorrect tracker operation.  The downwelling hemispheric shortwave 
PSP instrument mounted on Skyrad will not be affected by incorrect tracker operation.

• null(Raw data stream - documentation not supported)

• Shortwave Direct Normal Irradiance, Pyrgeometer, Minima(short_direct_normal_min)
• Downwelling Shortwave Diffuse Hemispheric Irradiance, Ventilated Pyranometer,
  Maxima(down_short_diffuse_hemisp_max)
• Shortwave Direct Normal Irradiance, Pyrgeometer(short_direct_normal)
• Downwelling Shortwave Diffuse Hemispheric Irradiance, Ventilated Pyranometer,
  Minima(down_short_diffuse_hemisp_min)
• Downwelling Shortwave Hemispheric Irradiance, Pyranometer, Standard Deviation(down_short_diffuse_hemisp_std)
• Shortwave Direct Normal Irradiance, Pyrgeometer, Maxima(short_direct_normal_max)
• Shortwave Direct Normal Irradiance, Pyrgeometer, Standard Deviation(short_direct_normal_std)
• Downwelling Shortwave Diffuse Hemispheric Irradiance, Ventilated Pyranometer(down_short_diffuse_hemisp)

• Instantaneous Direct Normal Shortwave Irradiance, Pyheliometer Thermopile
  Voltage(inst_direct_normal)
• Instantaneous Uncorrected Downwelling Shortwave Diffuse, Shaded Pyranometer
  Thermopile Voltage(inst_diffuse)

TWP/GNDRAD/C3 - IRT malfunction

The internal IRT power supply failed (probably due to a lightning strike on 11/14) and was 
drawing excessive current on the data logger's DC system. The problem was corrected by 
replacing the instrument with a spare.

• Surface Infra-Red Temperature, Standard Deviation(sfc_ir_temp_std)
• Surface Infra-Red Temperature Minima(sfc_ir_temp_min)
• Effective Surface (Skin) Temperature(sfc_ir_temp)
• Surface Infra-Red Temperature Maxima(sfc_ir_temp_max)

TWP/SKYRAD/C3 - IRT damaged

The analog output of the IRT was damaged by a lightning strike. The problem was corrected 
by replacing the instrument with a spare. The damaged IRT was returned to the vendor for 
repair.

• Sky Infra Red Temperature Minima(sky_ir_temp_min)
• Sky Infra-Red Temperature(sky_ir_temp)
• Standard Deviation of Sky Infra Red Temperature(sky_ir_temp_std)

• Instantaneous Sky/Cloud Infrared(inst_sky_ir_signal)

TWP/GNDRAD/C3 - IRT power

The IRT failed to report after a planned power outage to add lightning protection modules 
to the AC power wiring. The problem was corrected when a loose power connection to the 
logger was found, rectified, and power restored to the logger.

• Surface Infra-Red Temperature, Standard Deviation(sfc_ir_temp_std)
• Surface Infra-Red Temperature Minima(sfc_ir_temp_min)
• Effective Surface (Skin) Temperature(sfc_ir_temp)
• Surface Infra-Red Temperature Maxima(sfc_ir_temp_max)

TWP/GNDRAD/C3 - IRT failed

The IRT began to fail on 4/7/2006 and failed completely (apparently due to the internal 
power supply) on 4/27. It was replaced on 5/18.

• Surface Infra-Red Temperature, Standard Deviation(sfc_ir_temp_std)
• Surface Infra-Red Temperature Minima(sfc_ir_temp_min)
• Effective Surface (Skin) Temperature(sfc_ir_temp)
• Surface Infra-Red Temperature Maxima(sfc_ir_temp_max)

TWP/GNDRAD/C3 - Reprocess: Longwave Calibration error

Modified pyrgeometer calibration procedures were implemented beginning in December 2003.  
These modified procedures introduced a calibration bias in the longwave data.  The 
previous procedures were re-implemented at all sites between December 2005 and February 2006 to 
restore proper calibrations.                                                             
                The data collected while the incorrect procedures were in place are 
being reprocessing to remove the calibration bias.  Note, this also affected standard 
deviation, maximum and minimum data fields.

• Upwelling (10 meter) Longwave Hemispheric Irradiance, Pyrgeometer(up_long_hemisp)

TWP/GNDRAD/C3 - IRT bias

The IRT reported higher surface temperatures than the PIR due to corrosion on the 
terminals of the lightning protection module and a ground wire error. The corrosion was cleaned 
and the wiring corrected.

• Surface Infra-Red Temperature, Standard Deviation(sfc_ir_temp_std)
• Surface Infra-Red Temperature Minima(sfc_ir_temp_min)
• Effective Surface (Skin) Temperature(sfc_ir_temp)
• Surface Infra-Red Temperature Maxima(sfc_ir_temp_max)

TWP/SKYRAD/C3 - NIP Failure

Skyrad normal incident shortwave irradiance (NIP) started reporting impossible values for 
direct normal irradiance starting 16 November approx 2100GMT corresponding to a rain 
event at the same time.

The NIP was replaced fixing the problem.

Direct normal data are not recoverable.  However, the NIP data can be calculated from the 
global hemsipherical shortwave and global hemispherical diffuse datastreams by using the 
following relationship:
Global Horizontal = Direct Normal x cos(Z) + Diffuse Horizontal 
where Z is the zenith angle.

• Shortwave Direct Normal Irradiance, Pyrgeometer, Minima(short_direct_normal_min)
• Shortwave Direct Normal Irradiance, Pyrgeometer(short_direct_normal)
• Shortwave Direct Normal Irradiance, Pyrgeometer, Maxima(short_direct_normal_max)
• Shortwave Direct Normal Irradiance, Pyrgeometer, Standard Deviation(short_direct_normal_std)

• Instantaneous Direct Normal Shortwave Irradiance, Pyheliometer Thermopile
  Voltage(inst_direct_normal)

TWP/SKYRAD/C3 - NIP instrument failure

The NIP (Short Direct Normal) was replaced after it displayed symptoms of failure 
associated with either unknown precipitation related issues or a possible lightning strike.

NIP data are not recoverable.  Direct normal data can be reconstructed from global 
hemispheric and global diffuse data using the following relationship:
   global hemispheric = direct*cos(sza) + diffuse hemispheric

• null(Raw data stream - documentation not supported)

• Shortwave Direct Normal Irradiance, Pyrgeometer, Minima(short_direct_normal_min)
• Shortwave Direct Normal Irradiance, Pyrgeometer(short_direct_normal)
• Shortwave Direct Normal Irradiance, Pyrgeometer, Maxima(short_direct_normal_max)
• Shortwave Direct Normal Irradiance, Pyrgeometer, Standard Deviation(short_direct_normal_std)

• Instantaneous Direct Normal Shortwave Irradiance, Pyheliometer Thermopile
  Voltage(inst_direct_normal)

TWP/GNDRAD/C3 - Gndrad shutdown for tropical cylone

On Jan 3rd approximately 1000GMT the effects of a tropical cyclone started affecting the 
installed radiometer measurements at ARM/TWP/C3(Darwin) - both Skyrad and Gndrad.  On Jan 
4th 0740 GMT the Gndrad station was shutdown to avoid damage due to the close passing of 
this storm.  Station was restarted Jan 7th 0515GMT.

• null(Raw data stream - documentation not supported)

• lon(lon)
• Instantaneous Upwelling Pyrgeometer Dome Thermistor Resistance, Pyrgeometer(inst_up_long_dome_resist)
• lat(lat)
• Dummy altitude for Zeb(alt)
• Instantaneous Upwelling Pyrgeometer Thermopile(inst_up_long_hemisp_tp)
• Time offset of tweaks from base_time(time_offset)
• Instantaneous Upwelling Pyrgeometer Case Thermistor Resistance, Pyrgeometer(inst_up_long_case_resist)
• base time(base_time)

• Time offset of tweaks from base_time(time_offset)
• Instantaneous Surface Infra-Red Signal(inst_sfc_ir_signal)
• Instantaneous Upwelling Shortwave Hemispheric Irradiance, Pyranometer(inst_up_short_hemisp)
• time(time)
• base time(base_time)
• Dummy altitude for Zeb(alt)
• Instantaneous Upwelling Pyrgeometer Thermopile(inst_up_long_hemisp_tp)
• lat(lat)
• lon(lon)

• Upwelling (10 meter) Shortwave Hemispheric Irradiance, Pyranometer, Standard
  Deviation(up_short_hemisp_std)
• Upwelling (10 meter) Shortwave Hemispheric Irradiance, Pyranometer(up_short_hemisp)
• Surface Infra-Red Temperature Minima(sfc_ir_temp_min)
• lat(lat)
• Surface Infra-Red Temperature Maxima(sfc_ir_temp_max)
• Surface Infra-Red Temperature, Standard Deviation(sfc_ir_temp_std)
• Effective Surface (Skin) Temperature(sfc_ir_temp)
• Upwelling (10 meter) Longwave Hemispheric Irradiance, Pyrgeometer, Minima(up_long_hemisp_min)
• Upwelling (10 meter) Shortwave Hemispheric Irradiance, Pyranometer, Maxima(up_short_hemisp_max)
• Logger panel temperature(logger_temp)
• Upwelling (10 meter) Shortwave Hemispheric Irradiance, Pyranometer, Minima(up_short_hemisp_min)
• Upwelling (10 meter) Longwave Hemispheric Irradiance, Pyrgeometer, Maxima(up_long_hemisp_max)
• lon(lon)
• Upwelling (10 meter) Longwave Hemispheric Irradiance, Pyrgeometer, Standard
  Deviation(up_long_hemisp_std)
• base time(base_time)
• Upwelling (10 meter) Longwave Hemispheric Irradiance, Pyrgeometer(up_long_hemisp)
• Time offset of tweaks from base_time(time_offset)
• Dummy altitude for Zeb(alt)

TWP/SKYRAD/C3 - IRT power supply

The 12-to-24V DC converter the provides power to the IRT had shut down and was restarted 
by power-cycling.

• Sky Infra Red Temperature Minima(sky_ir_temp_min)
• Sky Infra-Red Temperature(sky_ir_temp)
• Sky Infra Red Temperature Maxima(sky_ir_temp_max)
• Standard Deviation of Sky Infra Red Temperature(sky_ir_temp_std)

TWP/SKYRAD/C3 - Contamination

The IRT exhibited a positive bias compared to AERI. The problem was corrected when the 
lens and mirror were cleaned.

• Sky Infra Red Temperature Minima(sky_ir_temp_min)
• Sky Infra-Red Temperature(sky_ir_temp)
• Sky Infra Red Temperature Maxima(sky_ir_temp_max)
• Standard Deviation of Sky Infra Red Temperature(sky_ir_temp_std)

TWP/SKYRAD/C3 - Direct normal instrument failure

The NIP instrument (short_direct_normal data stream) failed giving bad data during this 
time period.  The failure start time coincides with a reported DC power failure but no 
connection between the reported power failure and the failure of this instrument could be 
determined. 

Ops also reported the tracker clock running 2.9 minutes slow during maintenance on 12/22 
0300GMT (see CS-2008-0714).  Again, the slow clock is not suspect and did not appear to 
affect alignment.

Ops replaced the NIP instrument on 12/30 and short_direct_normal data resumed normal 
operation.

Disregard the short_direct_normal (NIP) data during this time period or calculate using 
the global and diffuse instruments and the following relationship:
short_direct_normal = ((down_short_hemisp - down_short_diffuse_hemisp))/cos(zenith angle)

• Shortwave Direct Normal Irradiance, Pyrgeometer, Minima(short_direct_normal_min)
• Shortwave Direct Normal Irradiance, Pyrgeometer(short_direct_normal)
• Shortwave Direct Normal Irradiance, Pyrgeometer, Maxima(short_direct_normal_max)
• Shortwave Direct Normal Irradiance, Pyrgeometer, Standard Deviation(short_direct_normal_std)

• Instantaneous Direct Normal Shortwave Irradiance, Pyheliometer Thermopile
  Voltage(inst_direct_normal)

TWP/SKYRAD/C3 - Tracker inoperative

The tracker at Darwin failed 01/23.  The tracker was power cycled on 01/27 and it returned 
to normal operation.

The affected data streams are short_direct_normal (NIP) and down_short_diffuse_hemisp 
(8-48).  

The down_short_hemisp are not affected.  

The down_long_hemisp1 and 2 (PIR1 and PIR2) should not be affected but direct sun can 
affect individual instrument performance.

• Downwelling Longwave Hemispheric Irradiance, Pyrgeometer1, Standard Deviation(down_long_hemisp1_std)
• Downwelling Shortwave Diffuse Hemispheric Irradiance, Ventilated Pyranometer,
  Maxima(down_short_diffuse_hemisp_max)
• Downwelling Longwave Hemispheric Irradiance, Pyrgeometer2, Minima(down_long_hemisp2_min)
• Downwelling Longwave Hemispheric Irradiance, Pyrgeometer1, Minima(down_long_hemisp1_min)
• Shortwave Direct Normal Irradiance, Pyrgeometer(short_direct_normal)
• Downwelling Longwave Hemispheric Irradiance, Pyrgeometer2, Standard Deviation(down_long_hemisp2_std)
• Instantaneous Downwelling Pyrgeometer Thermopile, Pyrgeometer2(inst_down_long_hemisp2_tp)
• Shortwave Direct Normal Irradiance, Pyrgeometer, Standard Deviation(short_direct_normal_std)
• Shortwave Direct Normal Irradiance, Pyrgeometer, Minima(short_direct_normal_min)
• Downwelling Shortwave Diffuse Hemispheric Irradiance, Ventilated Pyranometer,
  Minima(down_short_diffuse_hemisp_min)
• Downwelling Longwave Hemispheric Irradiance, Pyrgeometer2, Maxima(down_long_hemisp2_max)
• Instantaneous Downwelling Pyrgeometer Case Thermistor Temperature, Pyrgeometer1(inst_down_long_hemisp1_case_temp)
• Shortwave Direct Normal Irradiance, Pyrgeometer, Maxima(short_direct_normal_max)
• Downwelling Shortwave Hemispheric Irradiance, Pyranometer, Standard Deviation(down_short_diffuse_hemisp_std)
• Downwelling Longwave Hemispheric Irradiance, Pyrgeometer2(down_long_hemisp2)
• Downwelling Shortwave Diffuse Hemispheric Irradiance, Ventilated Pyranometer(down_short_diffuse_hemisp)
• Instantaneous Downwelling Pyrgeometer Dome Thermistor Temperature, Pyrgeometer2(inst_down_long_hemisp2_dome_temp)
• Downwelling Longwave Hemispheric Irradiance, Pyrgeometer1(down_long_hemisp1)
• Downwelling Longwave Hemispheric Irradiance, Pyrgeometer1, Maxima(down_long_hemisp1_max)
• Instantaneous Downwelling Pyrgeometer Thermopile, Pyrgeometer1(inst_down_long_hemisp1_tp)
• Instantaneous Downwelling Pyrgeometer Case Thermistor Temperature, Pyrgeometer2(inst_down_long_hemisp2_case_temp)
• Instantaneous Downwelling Pyrgeometer Dome Thermistor Temperature, Pyrgeometer1(inst_down_long_hemisp1_dome_temp)

• Instantaneous Downwelling Pyrgeometer Case Thermistor Resistance, Pyrgeometer2(inst_down_long_hemisp2_case_resist)
• Instantaneous Downwelling Pyrgeometer Case Thermistor Resistance, Pyrgeometer1(inst_down_long_hemisp1_case_resist)
• Instantaneous Direct Normal Shortwave Irradiance, Pyheliometer Thermopile
  Voltage(inst_direct_normal)
• Instantaneous Downwelling Pyrgeometer Dome Thermistor Resistance, Pyrgeometer2(inst_down_long_hemisp2_dome_resist)
• Instantaneous Downwelling Pyrgeometer Thermopile, Pyrgeometer1(inst_down_long_hemisp1_tp)
• Instantaneous Downwelling Pyrgeometer Thermopile, Pyrgeometer2(inst_down_long_hemisp2_tp)
• Instantaneous Downwelling Pyrgeometer Dome Thermistor Resistance, Pyrgeometer1(inst_down_long_hemisp1_dome_resist)
• Instantaneous Uncorrected Downwelling Shortwave Diffuse, Shaded Pyranometer
  Thermopile Voltage(inst_diffuse)