DQR ID | Subject | Data Streams Affected |
---|---|---|
D000919.1 | SGP/SIRS/C1 - Reprocess: 4/24 - 5/9 Data at C1 | sgpsirsC1.a1 |
D010423.1 | SGP/SIRS/C1 - Diffuse Pyranometer Thermal Offsets | sgpsirsC1.a0, sgpsirsC1.a1 |
D011211.1 | SGP/SIRS/C1 - Reprocess: Wire are switched | sgpsirsC1.a1 |
D030917.16 | SGP/SIRS/C1 - Missing data due to Ice storm and clock problems | sgpsirsC1.00, sgpsirsC1.a2, sgpsirsC1.b1, sgpsirs20sC1.a0, sgpsirs60sC1.a1, sgp1swfanalsirs1longC1.c1, sgp15swfanalsirs1longC1.c1 |
D040907.1 | SGP/SIRS/C1/E13 - Incorrect calibration coefficients | sgpsirsC1.00, sgpsirsC1.b1, sgpsirsE13.00, sgpsirsE13.b1, sgpsirs20sC1.a0, sgpsirs20sE13.a0 |
D050106.4 | SGP/SIRS/C1 - Reprocess: UIR/DIR Incorrect calibration coefficients | sgpsirsC1.00, sgpsirsC1.b1 |
D050206.2 | SGP/SIRS/C1 - Monthly Summary | sgpsirsC1.b1 |
D050929.1 | SGP/SIRS/C1 - sun tracker power failure | sgpsirsC1.00, sgpsirsC1.b1, sgpsirs20sC1.a0 |
D060630.8 | SGP/SIRS/C1 - Reprocess: Longwave Calibration error | sgpsirsC1.b1 |
Start Date | Start Time | End Date | End Time |
---|---|---|---|
04/24/2000 | 1900 | 05/08/2000 | 2359 |
Subject: | SGP/SIRS/C1 - Reprocess: 4/24 - 5/9 Data at C1 |
DataStreams: | sgpsirsC1.a1 |
Description: | Magnitude of data is correct, however, 2 wires were crossed producing negative values for SW Global Down, SW Global Up, SW Direct Normal, and SW Diffuse Down. Problem has been fixed at site. |
Measurements: | sgpsirsC1.a1:
|
Start Date | Start Time | End Date | End Time |
---|---|---|---|
03/21/1997 | 1648 | 02/22/2001 | 2050 |
Subject: | SGP/SIRS/C1 - Diffuse Pyranometer Thermal Offsets |
DataStreams: | sgpsirsC1.a0, sgpsirsC1.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: | sgpsirsC1.a0:
sgpsirsC1.a1:
|
Start Date | Start Time | End Date | End Time |
---|---|---|---|
05/10/2000 | 0000 | 06/30/2000 | 2359 |
Subject: | SGP/SIRS/C1 - Reprocess: Wire are switched |
DataStreams: | sgpsirsC1.a1 |
Description: | Upwelling longwave and downwelling longwave values are switched. Instrument Engineering logs (OMIS) indicate the following: "T/S indicated that the readings may be caused by the sensor wires being switched around. Switched the wires labeled 5H with the wire labeled 5L on the data logger. The readings on the DIR went from minus readings to positive readings. Will await further instruction from site scientist to perform any other PM". |
Measurements: | sgpsirsC1.a1:
|
Start Date | Start Time | End Date | End Time |
---|---|---|---|
03/09/2002 | 2101 | 03/10/2002 | 2125 |
03/13/2002 | 1801 | 03/14/2002 | 1602 |
Subject: | SGP/SIRS/C1 - Missing data due to Ice storm and clock problems |
DataStreams: | sgpsirsC1.00, sgpsirsC1.a2, sgpsirsC1.b1, sgpsirs20sC1.a0, sgpsirs60sC1.a1, sgp1swfanalsirs1longC1.c1, sgp15swfanalsirs1longC1.c1 |
Description: | Data are missing due to power failures caused by an ice storm and resulting system/instrument clock problems. |
Measurements: | sgp1swfanalsirs1longC1.c1:
sgpsirsC1.b1:
sgpsirsC1.00:
sgpsirs60sC1.a1:
sgp15swfanalsirs1longC1.c1:
sgpsirs20sC1.a0:
sgpsirsC1.a2:
|
Start Date | Start Time | End Date | End Time |
---|---|---|---|
08/27/2004 | 1830 | 09/07/2004 | 2130 |
Subject: | SGP/SIRS/C1/E13 - Incorrect calibration coefficients |
DataStreams: | sgpsirsC1.00, sgpsirsC1.b1, sgpsirsE13.00, sgpsirsE13.b1, sgpsirs20sC1.a0, sgpsirs20sE13.a0 |
Description: | After the DIR changeout on 8/27, the DLH measurements at the central facility vary significantly between pyrgeometers by as much as 65 Wm^(-2). It was discovered that the two downwelling pyrgeometers destined for C1 and E13 may have been swapped during installation. The instrument mentor is unsure of applied calibration coefficients during this DQR's time period. Backing out new downwelling longwave irradiances would be difficult in this case. Fortunately, the problem period is less than a fortnight. |
Measurements: | sgpsirsE13.b1:
sgpsirsC1.b1:
sgpsirsC1.00:
sgpsirs20sE13.a0:
sgpsirs20sC1.a0:
sgpsirsE13.00:
|
Start Date | Start Time | End Date | End Time |
---|---|---|---|
09/27/2004 | 1429 | 01/07/2005 | 1623 |
Subject: | SGP/SIRS/C1 - Reprocess: UIR/DIR Incorrect calibration coefficients |
DataStreams: | sgpsirsC1.00, sgpsirsC1.b1 |
Description: | It appears the datalogger program at SIRS/C1 was automatically updated, unbeknownst to anyone, on 9/27/20041423GMT with an older program with incorrect UIR and DIR calibration coefficients. The correct and incorrect cal coeffs for the UIR and DIR pyrgeometers during this DQR period were: incorrectUIR correctUIR K0 -12.84 -13.00 K1 .2250 0.2573 K2 1.024 1.024 K3 -1.9280 -1.8050 incorrectDIR correctDIR K0 -13.15 -26.89 K1 0.2374 0.2967 K2 1.0260 1.0560 K3 -2.478 -3.3080 |
Measurements: | sgpsirsC1.b1:
sgpsirsC1.00:
|
Start Date | Start Time | End Date | End Time |
---|---|---|---|
12/01/2004 | 0000 | 01/01/2005 | 0000 |
Subject: | SGP/SIRS/C1 - Monthly Summary |
DataStreams: | sgpsirsC1.b1 |
Description: | dominant problem here is the daytime 3 component problem. Direct and Diffuse are always too high and Global is too low. The problem occurs around the time that the testing regime switches from twilight to daytime testing regimes or from daytime to twilight. The flags occur in significant numbers on the 1st - 5th, 8th - 20th, 24th - 28th, 30th, and 31st. The failures vary in magnitude and duration. The worst flags for a particular day is typically high level yellow, with respect to this problem. Global goes below daytime empirical limits on both the 5th and 6th for substantial periods of time. Diffuse also goes below daytime empirical limits on the 6th in the evening. Upwelling Longwave is below empirical limits on the 24th. This may not be a problem, as many sites exhibited the same problem on the same night. Exceptionally cold temperatures may be the cause. Direct also exceeds its daytime empirical limit on the 1st, 4th, 10th, 13th, 14th, and 20th. This occurs at the changeover from medium to high air mass and does not last for longer than 30 minutes. |
Measurements: | sgpsirsC1.b1:
|
Start Date | Start Time | End Date | End Time |
---|---|---|---|
09/27/2005 | 1430 | 09/27/2005 | 1630 |
Subject: | SGP/SIRS/C1 - sun tracker power failure |
DataStreams: | sgpsirsC1.00, sgpsirsC1.b1, sgpsirs20sC1.a0 |
Description: | C1 experienced a sun tracker power faulure. The tracker was reset by onsite personnel shortly after the power failed. Only shaded and direct instruments were affected - i.e. the downwelling diffuse measurement from the 8-48 B&W pyranometer and the direct normal measurement from the NIP pyrheliometer. The downwelling longwave PIR data was unaffected by this event. |
Measurements: | sgpsirsC1.b1:
sgpsirsC1.00:
sgpsirs20sC1.a0:
|
Start Date | Start Time | End Date | End Time |
---|---|---|---|
12/11/2003 | 1950 | 02/16/2006 | 1901 |
Subject: | SGP/SIRS/C1 - Reprocess: 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 are being reprocessing to remove the calibration bias. Note, this also affected standard deviation, maximum and minimum data fields. |
Measurements: | sgpsirsC1.b1:
|