DQR ID | Subject | Data Streams Affected |
---|---|---|
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 |
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: | twpgndradC2.00:
twpgndrad60sC2.b1:
|
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:
|