DQR ID | Subject | Data Streams Affected |
---|---|---|
D030730.1 | TWP/GNDRAD/C2 - IRT problem | twpgndrad60sC2.b1 |
D041015.3 | TWP/GNDRAD/C2 - incorrect IRT calibration | twpgndrad60sC2.b1 |
D050504.2 | TWP/GNDRAD/C2 - IRT connector | twpgndrad60sC2.b1 |
D050815.1 | TWP/GNDRAD/C2 - IRT power supply failed | twpgndradC2.00, twpgndrad60sC2.b1 |
D050926.6 | TWP/GNDRAD/C2 - Gndrad inverted for radiometer | twpgndrad60sC2.b1 |
D060630.35 | TWP/GNDRAD/C2 - Reprocess: Longwave Calibration error | twpgndrad60sC2.b1 |
D070110.1 | TWP/GNDRAD/C2 - IRT signal | twpgndrad60sC2.b1 |
D070406.6 | TWP/GNDRAD/C2 - Reprocess: IRT calibration | twpgndrad60sC2.b1 |
D071204.1 | TWP/GNDRAD/C2 - Reprocessed: Incorrect calibration | twpgndrad20sC2.a0, twpgndrad60sC2.b1 |
Start Date | Start Time | End Date | End Time |
---|---|---|---|
07/12/2003 | 2100 | 09/14/2003 | 1100 |
Subject: | TWP/GNDRAD/C2 - IRT problem |
DataStreams: | twpgndrad60sC2.b1 |
Description: | The GNDRAD IRT exhibited a positive bias compared to the PIR from 2100 to 0700 UTC each day. The problem was corrected by removing the signal cable, cleaning the contacts, and reconnecting the cable. |
Measurements: | twpgndrad60sC2.b1:
|
Start Date | Start Time | End Date | End Time |
---|---|---|---|
07/05/2004 | 0501 | 07/19/2004 | 0206 |
Subject: | TWP/GNDRAD/C2 - incorrect IRT calibration |
DataStreams: | twpgndrad60sC2.b1 |
Description: | When the GNDRAD data logger was upgraded, the calibration offset for the IRT was initially incorrect. |
Measurements: | twpgndrad60sC2.b1:
|
Start Date | Start Time | End Date | End Time |
---|---|---|---|
03/27/2005 | 2330 | 04/03/2005 | 0240 |
Subject: | TWP/GNDRAD/C2 - IRT connector |
DataStreams: | twpgndrad60sC2.b1 |
Description: | The IRT had a problem with the connector of either the signal or power cable which produced an output of 0 volts equivalent to a measurement of 223K. The problem was corrected when the connectors were cleaned and tightened. |
Measurements: | twpgndrad60sC2.b1:
|
Start Date | Start Time | End Date | End Time |
---|---|---|---|
08/11/2005 | 1648 | 08/16/2005 | 2230 |
Subject: | TWP/GNDRAD/C2 - IRT power supply failed |
DataStreams: | twpgndradC2.00, twpgndrad60sC2.b1 |
Description: | The IRT output dropped to its minimum output of 223 K (0 volts). It was determined the 24 V DC converter had failed. The converter was replaced on 16 August and the instrument began reporting normally again. The IRT data are unusable during the five day period when the DC converter was faulty. The GNDRAD (down-looking) IRT is used primarily for surface temperature. The PIR can be used for this purpose by inverting the IR flux equation, Flux = sigma*temperature^4 where sigma = 5.67x10-8 W/m^2K^4. But, unlike the IRT, the PIR measurement is strongly effected by the air temperature in addition to the surface temperature. At night, when the air temperature approaches the surface temperature, the PIR provides a good estimate of the surface temperature. During the day, however, the PIR tends to underestimate the ground temperature, particularly on sunny days. The magnitude of the underestimate can be estimated by evaluating periods when both instruments are operating but is typically on the order of 5-10C. |
Measurements: | twpgndrad60sC2.b1:
twpgndradC2.00:
|
Start Date | Start Time | End Date | End Time |
---|---|---|---|
09/17/2005 | 0152 | 09/23/2005 | 0115 |
Subject: | TWP/GNDRAD/C2 - Gndrad inverted for radiometer |
DataStreams: | twpgndrad60sC2.b1 |
Description: | Gndrad instruments PIR and PSP inverted for replacement instrument installation and comparison |
Measurements: | twpgndrad60sC2.b1:
|
Start Date | Start Time | End Date | End Time |
---|---|---|---|
07/05/2004 | 2202 | 12/21/2005 | 2149 |
Subject: | TWP/GNDRAD/C2 - Reprocess: Longwave Calibration error |
DataStreams: | twpgndrad60sC2.b1 |
Description: | 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. |
Measurements: | twpgndrad60sC2.b1:
|
Start Date | Start Time | End Date | End Time |
---|---|---|---|
12/03/2006 | 0400 | 02/04/2007 | 2316 |
Subject: | TWP/GNDRAD/C2 - IRT signal |
DataStreams: | twpgndrad60sC2.b1 |
Description: | When the other GNDRAD radiometers were replaced on 12/3/2006, the quality of the IRT signal began to degrade until 12/26 when it became unusable. The instrument was replaced on 2/4/2007. |
Measurements: | twpgndrad60sC2.b1:
|
Start Date | Start Time | End Date | End Time |
---|---|---|---|
02/04/2007 | 2317 | 02/17/2007 | 0400 |
Subject: | TWP/GNDRAD/C2 - Reprocess: IRT calibration |
DataStreams: | twpgndrad60sC2.b1 |
Description: | The configuration of the IRT was set to that used at TWP/C3. This caused the calibration of the data to be wrong. It was corrected by reconfiguring the IRT to match the datalogger program. These data can be reprocessed and corrected by adding 10K, i.e. sfc_ir_temp(new) = sfc_ir_temp(old) + 10K. |
Measurements: | twpgndrad60sC2.b1:
|
Start Date | Start Time | End Date | End Time |
---|---|---|---|
11/25/2007 | 2202 | 11/30/2007 | 1724 |
Subject: | TWP/GNDRAD/C2 - Reprocessed: Incorrect calibration |
DataStreams: | twpgndrad20sC2.a0, twpgndrad60sC2.b1 |
Description: | The Gndrad PSP was changed out 11/25 but the datalogger program was not updated until 11/30. PSP #31293 installed 20071125.2202. Correct calibration coefficient = 123.46. Reprocessed to correct upwelling shortwave hemispheric irradiance (US) by: US(new) = (US(old) / 123.56 ) * 123.46 Reprocessing completed March 2008. |
Measurements: | twpgndrad60sC2.b1:
twpgndrad20sC2.a0:
|