DQR ID | Subject | Data Streams Affected |
---|---|---|
D040322.1 | SGP/SIRS/C1 - Discrepancy between measured and derived downwelling shortwave hemispheric | sgpsirs20sC1.a0, sgpsirsC1.b1 |
D060630.8 | SGP/SIRS/C1 - Reprocessed: Longwave Calibration error | sgpsirsC1.b1 |
Start Date | Start Time | End Date | End Time |
---|---|---|---|
03/18/2004 | 1500 | 06/10/2004 | 2000 |
Subject: | SGP/SIRS/C1 - Discrepancy between measured and derived downwelling shortwave hemispheric |
DataStreams: | sgpsirs20sC1.a0, sgpsirsC1.b1 |
Description: | Measured values of downwelling hemispheric shortwave radiation were up to 40 W/m^2 higher than derived values during the afternoon hours. Analysis reveals that this is likely an artifact of the cosine response of the particular installed PSP coupled with typical uncertainties of this set of installed radiometers. That is, this particular instrument cluster seems to be producing cumulative errors on the high side of accepted values. The PSP contains the most uncertainty in measurement at this station. Users should use a derived value for the downwelling shortwave hemispheric irradiance (DS). Where DS = diffuse component + direct normal * cos(SZA) component described in the SIRS handbook Sec 7.2 available at: http://www.arm.gov/publications/tech_reports/handbooks/sirs_handbook.pdf |
Measurements: | sgpsirs20sC1.a0:
sgpsirsC1.b1:
|
Start Date | Start Time | End Date | End Time |
---|---|---|---|
12/11/2003 | 1950 | 02/16/2006 | 1901 |
Subject: | SGP/SIRS/C1 - Reprocessed: Longwave Calibration error |
DataStreams: | sgpsirsC1.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 have been reprocessed to remove the calibration bias. The reprocessed 60 second averaged data are based on 3 instantaneous 20 second data records rather than on 60 1 second instantaneous data records. Still, these data are considered far superior to the originally processed data. The reprocessed data were archived in October 2006. |
Measurements: | sgpsirsC1.b1:
|