DQR ID | Subject | Data Streams Affected |
---|---|---|
D010423.11 | SGP/SIRS/E10 - Diffuse Pyranometer Thermal Offsets | sgpsirsE10.a0, sgpsirsE10.a1 |
D010423.12 | SGP/SIRS/E11 - Diffuse Pyranometer Thermal Offsets | sgpsirsE11.a0, sgpsirsE11.a1 |
D010423.13 | SGP/SIRS/E12 - Diffuse Pyranometer Thermal Offsets | sgpsirsE12.a0, sgpsirsE12.a1 |
D010423.15 | SGP/SIRS/E15 - Diffuse Pyranometer Thermal Offsets | sgpsirsE15.a0, sgpsirsE15.a1 |
D010423.16 | SGP/SIRS/E16 - Diffuse Pyranometer Thermal Offsets | sgpsirsE16.a0, sgpsirsE16.a1 |
D031124.4 | SGP/SIRS/E10 | sgpsirsE10.a0, sgpsirsE10.a1 |
D031124.5 | SGP/SIRS/E10 - | sgpsirsE10.a0, sgpsirsE10.a1 |
D031124.6 | SGP/SIRS/E11 | sgpsirsE11.a0, sgpsirsE11.a1 |
D031124.7 | SGP/SIRS/E11 - | sgpsirsE11.a0, sgpsirsE11.a1 |
D031229.1 | SGP/SIRS/E12 | sgpsirsE12.a0, sgpsirsE12.a1 |
D970927.1 | SIRS NIPs affected by condensation at E8, E11, E13, & E15 | sgpsirsE8.a1, sgpsirsE11.a1, sgpsirsE13.a1, sgpsirsE15.a1 |
D990716.15 | SGP/SIRS - SIRS E10 April 1999 (SERI-QC Results) | sgpsirsE10.a0, sgpsirsE10.a1 |
D990716.16 | SGP/SIRS - SIRS E11 April 1999 (SERI-QC Results) | sgpsirsE11.a0, sgpsirsE11.a1 |
D990716.17 | SGP/SIRS - SIRS E12 April 1999 (SERI-QC Results) | sgpsirsE12.a0, sgpsirsE12.a1 |
Start Date | Start Time | End Date | End Time |
---|---|---|---|
11/05/1997 | 0656 | 02/14/2001 | 1500 |
Subject: | SGP/SIRS/E10 - Diffuse Pyranometer Thermal Offsets |
DataStreams: | sgpsirsE10.a0, sgpsirsE10.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: | sgpsirsE10.a1:
sgpsirsE10.a0:
|
Start Date | Start Time | End Date | End Time |
---|---|---|---|
08/22/1997 | 0805 | 02/20/2001 | 2040 |
Subject: | SGP/SIRS/E11 - Diffuse Pyranometer Thermal Offsets |
DataStreams: | sgpsirsE11.a0, sgpsirsE11.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: | sgpsirsE11.a0:
sgpsirsE11.a1:
|
Start Date | Start Time | End Date | End Time |
---|---|---|---|
10/31/1997 | 0357 | 02/20/2001 | 1655 |
Subject: | SGP/SIRS/E12 - Diffuse Pyranometer Thermal Offsets |
DataStreams: | sgpsirsE12.a0, sgpsirsE12.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: | sgpsirsE12.a0:
sgpsirsE12.a1:
|
Start Date | Start Time | End Date | End Time |
---|---|---|---|
08/26/1997 | 1225 | 02/20/2001 | 1730 |
Subject: | SGP/SIRS/E15 - Diffuse Pyranometer Thermal Offsets |
DataStreams: | sgpsirsE15.a0, sgpsirsE15.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: | sgpsirsE15.a1:
sgpsirsE15.a0:
|
Start Date | Start Time | End Date | End Time |
---|---|---|---|
08/21/1997 | 0735 | 02/21/2001 | 1620 |
Subject: | SGP/SIRS/E16 - Diffuse Pyranometer Thermal Offsets |
DataStreams: | sgpsirsE16.a0, sgpsirsE16.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: | sgpsirsE16.a0:
sgpsirsE16.a1:
|
Start Date | Start Time | End Date | End Time |
---|---|---|---|
01/16/2000 | 1145 | 02/16/2000 | 1215 |
Subject: | SGP/SIRS/E10 |
DataStreams: | sgpsirsE10.a0, sgpsirsE10.a1 |
Description: | Direct (NIP) exceeds 5 W/m^2, triggering yellow flags. This test was designed more for daytime conditions. |
Measurements: | sgpsirsE10.a1:
sgpsirsE10.a0:
|
Start Date | Start Time | End Date | End Time |
---|---|---|---|
01/01/2000 | 0000 | 02/01/2000 | 0000 |
Subject: | SGP/SIRS/E10 - |
DataStreams: | sgpsirsE10.a0, sgpsirsE10.a1 |
Description: | Data quality this site-month is OK. Nighttime offsets for the Global (DS) and Diffuse (DD) pyranometers are -5 W/m^2 a piece. DS dips below its daytime empirical limits on the 3rd, 8th, 16th, and 27th for various lengths of time. DD goes below daytime empirical limits on the 8th from 15:15 to 17:30 GMT and goes below its nighttime empirical limit immidiately after sunset on the 19th. There are inconsistencies between the Global (DS), 11th, 12th, 13th, 25th, 30th, 31st in the afternoon. These inconsistencies range in severity from mild to substansial even though they all trigger yellow flags only (or stay green). In every case the DD and NIP are too high and the DS is too low. This could be caused by the use of a constant pyranometer responsivity for all solar zenith angles, or the switchover from daylight to twilight testing regimes. The daytime negative offset in the DS PSP is also a probable factor in the error. It should also be noted that the calibration plus or minus 3%. There are also two component (Gompertz boundaries) problems this month: NIP and DD are flagged as too high on the 3rd and 8th for short periods of time. There is a small but persistent problem with the Upwelling Shortwave (US) data during this time period. At dusk the US is below its twilight empirical limits almost every day at dusk. |
Measurements: | sgpsirsE10.a1:
sgpsirsE10.a0:
|
Start Date | Start Time | End Date | End Time |
---|---|---|---|
01/09/2000 | 1105 | 01/09/2000 | 1205 |
Subject: | SGP/SIRS/E11 |
DataStreams: | sgpsirsE11.a0, sgpsirsE11.a1 |
Description: | Direct (NIP) exceeds 5 W/m^2, triggering yellow flags. This test was designed more for daytime conditions. |
Measurements: | sgpsirsE11.a0:
sgpsirsE11.a1:
|
Start Date | Start Time | End Date | End Time |
---|---|---|---|
01/01/2000 | 0000 | 02/01/2000 | 0000 |
Subject: | SGP/SIRS/E11 - |
DataStreams: | sgpsirsE11.a0, sgpsirsE11.a1 |
Description: | Data quality this site-month is good. Nighttime offsets for the Global (DS) and Diffuse (DD) pyranometers are -5 W/m^2 a piece. There are also two component (Gompertz boundaries) problems this month: Direct (NIP) and DD are flagged as too high on the 3rd for a short period of time. DS dips below its daytime empirical limits on the 3rd and 23rd and Upwelling Longwave dips below the empirical limits from 12:20 to 14:50 GMT. The winter Longwave empirical limit of 250 W/m^2 is currently under further review. (A reading of 250 W/m^2 suggests a possible temperature between 5 and 20 degrees Fahrenheit.) Upwelling Shortwave (US) is below its nighttime empirical limit for a little while after the sun goes down on the 12th. |
Measurements: | sgpsirsE11.a0:
sgpsirsE11.a1:
|
Start Date | Start Time | End Date | End Time |
---|---|---|---|
01/01/2000 | 0000 | 02/01/2000 | 0000 |
Subject: | SGP/SIRS/E12 |
DataStreams: | sgpsirsE12.a0, sgpsirsE12.a1 |
Description: | Data quality this site-month is good. Nighttime offsets in the Downwelling pyranometer (DS) average about -4 W/m^2 for the month. The Downwelling Diffuse pyranometer (DD) averages about -5 W/m^2 for its nighttime offset. DD and DS go below daytime empirical limits late in the day on the 3rd and 8th late in the day and on the 16th early in the day. Diffuse also exceeds daytime empirical limits earlier in the day on the 3rd. There are moderate inconsistencies between the Global (DS), Direct (NIP) and Diffuse (DD) components for the 4th in the afternoon. DD and NIP are too high and the DS is too low. This could be caused by the use of a constant pyranometer responsivity for all solar zenith angles, or the switchover from daylight to twilight testing regimes. The daytime negative offset in the DS PSP is also a probable factor in the error. It should also be noted that the calibration factors for the PSP's have a tolerance of plus or minus 5% and the NIP has a tolerance of plus or minus 3%. |
Measurements: | sgpsirsE12.a0:
sgpsirsE12.a1:
|
Start Date | Start Time | End Date | End Time |
---|---|---|---|
09/26/1997 | 1230 | 09/26/1997 | 1330 |
09/26/1997 | 1230 | 09/26/1997 | 1345 |
09/26/1997 | 1230 | 09/26/1997 | 1415 |
Subject: | SIRS NIPs affected by condensation at E8, E11, E13, & E15 |
DataStreams: | sgpsirsE8.a1, sgpsirsE11.a1, sgpsirsE13.a1, sgpsirsE15.a1 |
Description: | Comparison of data from the unshaded PSP to that derived from the 'direct + diffuse' (NIP + shaded PSP) indicated low values of the 'direct+diffuse' combination starting at sunrise and lasting for about an hour at E8, E11, E13 and E15. Futher examination revealed that the NIPs were reading low and were likely affected by condensation during this brief period. Weather conditions were foggy over the area early that morning, and fog quickly dissipated after sunrise. |
Measurements: | sgpsirsE15.a1:
sgpsirsE11.a1:
sgpsirsE8.a1:
sgpsirsE13.a1:
|
Start Date | Start Time | End Date | End Time |
---|---|---|---|
04/01/1999 | 0001 | 04/30/1999 | 2359 |
Subject: | SGP/SIRS - SIRS E10 April 1999 (SERI-QC Results) |
DataStreams: | sgpsirsE10.a0, sgpsirsE10.a1 |
Description: | Data quality for this site is excellent this month. Daytime data are 100 % present. Of the present daytime data, 98% are at or below the 5% quality assurance threshold. Severe flags early in the morning on the 4th through the 21st, and on the 30th indicate that the DS, DD and NIP are above twilight empirical limits. Low-level flags later in the morning and around mid-day during the second week of the month indicate that the DS is too low by the three-component test, or that the DD or NIP is too high. Low-level flags late in the afternoon on clear or partly cloudy days indicate the opposite. Heavily overcast skies pushed the DS and DD below daytime or twilight empirical limits on a number of occasions. On the afternoon of the 22nd the NIP, along with the DD and DS signals, fell below daytime limits for a few minutes. Moderate flags later the same day indicate that the DS is too high by the three-component test. No problems are notes in the UIR, DIR or US signals. |
Measurements: | sgpsirsE10.a1:
sgpsirsE10.a0:
|
Start Date | Start Time | End Date | End Time |
---|---|---|---|
04/01/1999 | 0001 | 04/30/1999 | 2359 |
Subject: | SGP/SIRS - SIRS E11 April 1999 (SERI-QC Results) |
DataStreams: | sgpsirsE11.a0, sgpsirsE11.a1 |
Description: | Data quality for this site is very good this month. All daytime data are present, and 96% of the present daytime data earn passing or low-level flags. Low-level flags are seen in the early morning hours under clear to fair sky conditions, indicating that the DS (global horizontal) is too low, or that the NIP (direct normal) or DD (diffuse horizontal) is too high. Overcast skies cause the DD and DS to fall below twilight or daytime empirical limits on a number of occasions. The suntracker failed for an hour or so on the morning of the 6th. During Preventive Maintenance later in the morning the alignment was adjusted. No problems noted in the UIR, DIR or US signals. |
Measurements: | sgpsirsE11.a0:
sgpsirsE11.a1:
|
Start Date | Start Time | End Date | End Time |
---|---|---|---|
04/01/1999 | 0001 | 04/30/1999 | 2359 |
Subject: | SGP/SIRS - SIRS E12 April 1999 (SERI-QC Results) |
DataStreams: | sgpsirsE12.a0, sgpsirsE12.a1 |
Description: | Data quality at this site is very good this month. Not quite 100% of the data are present, and 91% of the present daytime data earned passing or low-level flags. Another 8.1% of the daytime data earn strange-but-true flags. Low-level flags seen from late morning to early afternoon on clear and partly cloudy days throughout the month indicate that the DS is too high by the three-component test. Alternatively, the DD or NIP may be too low. Heavily overcast skies drove the DS and DD below daytime or twilight empirical limits on a few occasions, and the NIP was forced below daytime empirical limits on the afternoon of the 22nd. On the 20th the phone line to the site was tested and found to be of poor quality for data transmittal. This is likely the cause of the spotty data retrieval from this site over the past several months. On the morning of the 21st the 10m tower was removed for upgrade so the US and UIR signals are missing recorded as 99999 by the data logger. No other problems are noted. |
Measurements: | sgpsirsE12.a0:
sgpsirsE12.a1:
|