DQR ID | Subject | Data Streams Affected |
---|---|---|
D000907.1 | SGP/SIRS/E24 - SIRS Signal Cable Damage at E24 | sgpsirsE24.00, sgpsirsE24.01, sgpsirsE24.a0, sgpsirsE24.a1 |
D010423.21 | SGP/SIRS/E22 - Diffuse Pyranometer Thermal Offsets | sgpsirsE22.a0, sgpsirsE22.a1 |
D010423.22 | SGP/SIRS/E24 - Diffuse Pyranometer Thermal Offsets | sgpsirsE24.a0, sgpsirsE24.a1 |
D040706.1 | SGP/SIRS/E22 - Failed NIP sensor cable | sgpsirs20sE22.a0, sgpsirsE22.00, sgpsirsE22.b1 |
D040712.1 | SGP/SIRS/E24 - NIP shaded near sunrise | sgpsirs20sE24.a0, sgpsirs60sE24.a1, sgpsirsE24.a2 |
D040712.2 | SGP/SIRS/E24 - NIP shaded near sunrise | sgpsirs20sE24.a0, sgpsirs60sE24.a1, sgpsirsE24.a2, sgpsirsE24.b1 |
D040712.3 | SGP/SIRS/E24 - NIP shaded near sunrise | sgpsirs20sE24.a0, sgpsirsE24.b1 |
D050227.1 | SGP/SIRS/E24 - Erratic downwelling shortwave data | sgpsirs20sE24.a0, sgpsirsE24.00, sgpsirsE24.b1 |
D050412.3 | SGP/SIRS/E24 - Dirt on dome | sgpsirs20sE24.a0, sgpsirsE24.00, sgpsirsE24.b1 |
D050520.1 | SGP/SIRS/E22 - Intermittent upwelling longwave data loss | sgpsirs20sE22.a0, sgpsirsE22.00, sgpsirsE22.b1 |
D060630.28 | SGP/SIRS/E22 - Reprocessed: Longwave Calibration error | sgpsirsE22.b1 |
D060630.29 | SGP/SIRS/E24 - Reprocessed: Longwave Calibration error | sgpsirsE24.b1 |
Start Date | Start Time | End Date | End Time |
---|---|---|---|
02/08/2000 | 0510 | 02/10/2000 | 1700 |
Subject: | SGP/SIRS/E24 - SIRS Signal Cable Damage at E24 |
DataStreams: | sgpsirsE24.00, sgpsirsE24.01, sgpsirsE24.a0, sgpsirsE24.a1 |
Description: | Cattle from adjoining field had broken the electric fence wire around the equipment and chewed radiometer cables in half adn damaged the shading arm(s) on the SciTec tracker. The NIP and DD shortwave data collected during this time were recorded by the logger as 'over-range' or 'open-channel' (with corresponding data values stored as '-99999') or a numeric value not representative of the real irradiance conditions due to faulty connections. Data for this period are to be considered MISSING. |
Measurements: | sgpsirsE24.00:
sgpsirsE24.a1:
sgpsirsE24.01:
sgpsirsE24.a0:
|
Start Date | Start Time | End Date | End Time |
---|---|---|---|
11/25/1997 | 0630 | 02/21/2001 | 2000 |
Subject: | SGP/SIRS/E22 - Diffuse Pyranometer Thermal Offsets |
DataStreams: | sgpsirsE22.a0, sgpsirsE22.a1 |
Description: | Broadband downwelling shortwave diffuse (sky) irradiance measurements available from SIRS during the period of this Data Quality Report (DQR), require adjustment for thermal offsets. These thermal, or ?zero? offsets refer to the generally reduced output signals from a shaded pyranometer due to the exchange of longwave (infrared) irradiance between the single black thermopile detector, the protective glass domes surrounding the detector, and the atmosphere. Originally considered an acceptable nighttime response of thermopile-type pyranometers, the generally negative bias is now recognized to significantly effect the accuracy of SIRS diffuse irradiance data during daylight periods. Studies of the Eppley Laboratory, Inc. Model PSP (Precision Spectral Pyranometer), used for the SIRS measurements of diffuse irradiance, suggest the thermal offset correction can range from near 0 to as much as 30 Watts per square meter, depending on the coincident net longwave, or infrared irradiance [1, 2]. Under very clear-sky conditions, the diffuse irradiance from a shaded PSP can be less than the minimum physical limit defined by radiative transfer model estimates based only on Rayleigh scattering effects. A correction method has been developed for adjusting SIRS diffuse irradiance data [3]. The resulting Value Added Product (VAP) will be applied to SIRS data for the period of this DQR. The VAP will not be applied to SIROS data collected before the instrument platform was converted to SIRS. Additionally, the Model PSP radiometer has been replaced by a Model 8-48 which uses a black and white thermopile detector known to reduce the thermal offset errors to less than 2 Watts per square meter [3]. The radiometer replacement at this SIRS location was completed on the ending date of this DQR. References: 1. Gulbrandsen, A., 1978: On the use of pyranometers in the study of spectral solar radiation and atmospheric aerosols. J. Appl. Meteorol., 17, 899-904. 2. Cess, R. D., X. Jing, T. Qian, and M. Sun, 1999: Validation strategies applied to the measurement of total, direct and diffuse shortwave radiation at the surface. J. Geophys. Res. 3. Dutton, E.G., J. Michalsky, T. Stoffel, B. Forgan, J. Hickey, D. Nelson, T. Alberta, and I. Reda, 2001: Measurement of Broadband Diffuse Solar Irradiance Using Current Commercial Instrumentation With a Correction for Thermal Offset Errors. J. Atmos. Oceanic Tech. Vol 18, No. 3, 297-314. (March 2001) |
Measurements: | sgpsirsE22.a0:
sgpsirsE22.a1:
|
Start Date | Start Time | End Date | End Time |
---|---|---|---|
12/03/1997 | 0730 | 02/22/2001 | 1615 |
Subject: | SGP/SIRS/E24 - Diffuse Pyranometer Thermal Offsets |
DataStreams: | sgpsirsE24.a0, sgpsirsE24.a1 |
Description: | Broadband downwelling shortwave diffuse (sky) irradiance measurements available from SIRS during the period of this Data Quality Report (DQR), require adjustment for thermal offsets. These thermal, or ?zero? offsets refer to the generally reduced output signals from a shaded pyranometer due to the exchange of longwave (infrared) irradiance between the single black thermopile detector, the protective glass domes surrounding the detector, and the atmosphere. Originally considered an acceptable nighttime response of thermopile-type pyranometers, the generally negative bias is now recognized to significantly effect the accuracy of SIRS diffuse irradiance data during daylight periods. Studies of the Eppley Laboratory, Inc. Model PSP (Precision Spectral Pyranometer), used for the SIRS measurements of diffuse irradiance, suggest the thermal offset correction can range from near 0 to as much as 30 Watts per square meter, depending on the coincident net longwave, or infrared irradiance [1, 2]. Under very clear-sky conditions, the diffuse irradiance from a shaded PSP can be less than the minimum physical limit defined by radiative transfer model estimates based only on Rayleigh scattering effects. A correction method has been developed for adjusting SIRS diffuse irradiance data [3]. The resulting Value Added Product (VAP) will be applied to SIRS data for the period of this DQR. The VAP will not be applied to SIROS data collected before the instrument platform was converted to SIRS. Additionally, the Model PSP radiometer has been replaced by a Model 8-48 which uses a black and white thermopile detector known to reduce the thermal offset errors to less than 2 Watts per square meter [3]. The radiometer replacement at this SIRS location was completed on the ending date of this DQR. References: 1. Gulbrandsen, A., 1978: On the use of pyranometers in the study of spectral solar radiation and atmospheric aerosols. J. Appl. Meteorol., 17, 899-904. 2. Cess, R. D., X. Jing, T. Qian, and M. Sun, 1999: Validation strategies applied to the measurement of total, direct and diffuse shortwave radiation at the surface. J. Geophys. Res. 3. Dutton, E.G., J. Michalsky, T. Stoffel, B. Forgan, J. Hickey, D. Nelson, T. Alberta, and I. Reda, 2001: Measurement of Broadband Diffuse Solar Irradiance Using Current Commercial Instrumentation With a Correction for Thermal Offset Errors. J. Atmos. Oceanic Tech. Vol 18, No. 3, 297-314. (March 2001) |
Measurements: | sgpsirsE24.a1:
sgpsirsE24.a0:
|
Start Date | Start Time | End Date | End Time |
---|---|---|---|
06/30/2004 | 0156 | 07/07/2004 | 1800 |
Subject: | SGP/SIRS/E22 - Failed NIP sensor cable |
DataStreams: | sgpsirs20sE22.a0, sgpsirsE22.00, sgpsirsE22.b1 |
Description: | The suntracker was driven past it optical limit switch and pulled the direct normal (NIP) instrument cable from its connector. |
Measurements: | sgpsirs20sE22.a0:
sgpsirsE22.b1:
sgpsirsE22.00:
|
Start Date | Start Time | End Date | End Time |
---|---|---|---|
04/08/2001 | 1200 | 05/20/2001 | 1300 |
07/26/2001 | 1300 | 09/06/2001 | 1200 |
Subject: | SGP/SIRS/E24 - NIP shaded near sunrise |
DataStreams: | sgpsirs20sE24.a0, sgpsirs60sE24.a1, sgpsirsE24.a2 |
Description: | The NIP is shaded by the EF laptop computer enclosure near sunrise during parts of the Spring and Summer. This has occurred from 04/08 to 05/20 and from 07/26 to 09/06 every year since 2001 and will occur during these date ranges in the future as well. The shading occurs for a few minutes each day between 1200 and 1300 GMT depending on the time of the year. For the early dates, shading occurs a little after 1200 GMT and by 05/20 shading happens nearer to 1300 GMT. In late July the shading occurs near 1300 GMT and closer to 1200 GMT by 09/06. |
Measurements: | sgpsirs20sE24.a0:
sgpsirs60sE24.a1:
sgpsirsE24.a2:
|
Start Date | Start Time | End Date | End Time |
---|---|---|---|
04/08/2002 | 1200 | 05/20/2002 | 1300 |
07/26/2002 | 1300 | 09/06/2002 | 1200 |
04/08/2003 | 1200 | 04/16/2003 | 1300 |
Subject: | SGP/SIRS/E24 - NIP shaded near sunrise |
DataStreams: | sgpsirs20sE24.a0, sgpsirs60sE24.a1, sgpsirsE24.a2, sgpsirsE24.b1 |
Description: | The NIP is shaded by the EF laptop computer enclosure near sunrise during parts of the Spring and Summer. This has occurred from 04/08 to 05/20 and from 07/26 to 09/06 every year since 2001 and will occur during these date ranges in the future as well. The shading occurs for a few minutes each day between 1200 and 1300 GMT depending on the time of the year. For the early dates, shading occurs a little after 1200 GMT and by 05/20 shading happens nearer to 1300 GMT. In late July the shading occurs near 1300 GMT and closer to 1200 GMT by 09/06. |
Measurements: | sgpsirs20sE24.a0:
sgpsirs60sE24.a1:
sgpsirsE24.b1:
sgpsirsE24.a2:
|
Start Date | Start Time | End Date | End Time |
---|---|---|---|
04/17/2003 | 1200 | 05/20/2003 | 1300 |
07/26/2003 | 1300 | 09/06/2003 | 1200 |
04/08/2004 | 1200 | 05/20/2004 | 1300 |
07/26/2004 | 1300 | 09/06/2004 | 1200 |
Subject: | SGP/SIRS/E24 - NIP shaded near sunrise |
DataStreams: | sgpsirs20sE24.a0, sgpsirsE24.b1 |
Description: | The NIP is shaded by the EF laptop computer enclosure near sunrise during parts of the Spring and Summer. This has occurred from 04/08 to 05/20 and from 07/26 to 09/06 every year since 2001 and will occur during these date ranges in the future as well. The shading occurs for a few minutes each day between 1200 and 1300 GMT depending on the time of the year. For the early dates, shading occurs a little after 1200 GMT and by 05/20 shading happens nearer to 1300 GMT. In late July the shading occurs near 1300 GMT and closer to 1200 GMT by 09/06. |
Measurements: | sgpsirs20sE24.a0:
sgpsirsE24.b1:
|
Start Date | Start Time | End Date | End Time |
---|---|---|---|
02/13/2005 | 1945 | 03/17/2005 | 1745 |
Subject: | SGP/SIRS/E24 - Erratic downwelling shortwave data |
DataStreams: | sgpsirs20sE24.a0, sgpsirsE24.00, sgpsirsE24.b1 |
Description: | Downwelling shortwave hemispheric readings are occasionally erratic, jumping to very high or very low values for short periods of time. SGP PM techs reseated all Downwelling Shortwave PSP instrument connections on 3/17/2005 approx 1945GMT. The problem did not reoccur after that time but the DS cable was replaced on 3/31/2005 approx 1815 GMT to ensure the problem did not reappear. |
Measurements: | sgpsirsE24.00:
sgpsirs20sE24.a0:
sgpsirsE24.b1:
|
Start Date | Start Time | End Date | End Time |
---|---|---|---|
04/07/2005 | 0000 | 04/14/2005 | 1610 |
Subject: | SGP/SIRS/E24 - Dirt on dome |
DataStreams: | sgpsirs20sE24.a0, sgpsirsE24.00, sgpsirsE24.b1 |
Description: | The Downwelling Shortwave Hemispheric (DSH) Irradiance data were erratic. The Pyranometer instrument dome at this site was likely dirty given the relatively large spread between the measured DSH and derived DSH readings during the middle part of the day (up to 50 W/m^2). Rain on 04/06 most likely contributed to this problem. Preventative maintenance on 4/14 effectively cleaned the pyranometer dome. Preventative maintenance reports indicate dry-water spots on dome when it was cleaned on 4/14. |
Measurements: | sgpsirsE24.00:
sgpsirs20sE24.a0:
sgpsirsE24.b1:
|
Start Date | Start Time | End Date | End Time |
---|---|---|---|
05/07/2005 | 0000 | 07/20/2005 | 2000 |
Subject: | SGP/SIRS/E22 - Intermittent upwelling longwave data loss |
DataStreams: | sgpsirs20sE22.a0, sgpsirsE22.00, sgpsirsE22.b1 |
Description: | Upwelling longwave hemispheric data drops out occasionally during the afternoon hours. Maintenance determined that the Upwelling LW Hemispheric irradiance instrument, the PIR, had a failed cable affecting only the thermopile measurement of this instrument. Cable was replaced 7/20/05 2000GMT. |
Measurements: | sgpsirs20sE22.a0:
sgpsirsE22.b1:
sgpsirsE22.00:
|
Start Date | Start Time | End Date | End Time |
---|---|---|---|
07/23/2003 | 1830 | 02/15/2006 | 1741 |
Subject: | SGP/SIRS/E22 - Reprocessed: Longwave Calibration error |
DataStreams: | sgpsirsE22.b1 |
Description: | Modified pyrgeometer calibration procedures were implemented beginning in July 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 August 2006. |
Measurements: | sgpsirsE22.b1:
|
Start Date | Start Time | End Date | End Time |
---|---|---|---|
07/24/2003 | 1640 | 02/16/2006 | 1705 |
Subject: | SGP/SIRS/E24 - Reprocessed: Longwave Calibration error |
DataStreams: | sgpsirsE24.b1 |
Description: | Modified pyrgeometer calibration procedures were implemented beginning in July 2004. 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: | sgpsirsE24.b1:
|