DQR ID | Subject | Data Streams Affected |
---|---|---|
D020805.1 | SGP/MWR/B6 - High noise level, poor calibration | sgpmwrlosB6.a0, sgpmwrlosB6.a1, sgpmwrlosB6.b1 |
D030121.2 | SGP/MWR/B6 - Incorrect MWR warmup configuration | sgpmwrlosB6.a1, sgpmwrlosB6.b1, sgpmwrtipB6.a1 |
D030312.10 | SGP/MWR/C1 - Intermittent Negative Sky Brightness Temperatures | sgp1mwravgC1.c1, sgp5mwravgC1.c1, sgpmwrlosC1.a1, sgpmwrlosC1.b1 |
D030312.2 | SGP/MWR/B1 - Intermittent Negative Sky Brightness Temperatures | sgpmwrlosB1.a1, sgpmwrlosB1.b1 |
D030312.3 | SGP/MWR/B4 - Intermittent Negative Sky Brightness Temperatures | sgpmwrlosB4.a1, sgpmwrlosB4.b1 |
D030312.4 | SGP/MWR/B5 - Intermittent Negative Sky Brightness Temperatures | sgpmwrlosB5.a1, sgpmwrlosB5.b1 |
D030312.5 | SGP/MWR/B6 - Intermittent Negative Sky Brightness Temperatures | sgpmwrlosB6.a1, sgpmwrlosB6.b1 |
D030822.1 | SGP/MWR/C1 - Incorrect min and max values | sgpmwrlosC1.b1 |
D030822.2 | SGP/MWR/B1 - min/max/delta values incorrect | sgpmwrlosB1.b1 |
D030822.3 | SGP/MWR/B4 - min/max/delta values incorrect | sgpmwrlosB4.b1 |
D030822.4 | SGP/MWR/B5 - min/max/delta values incorrect | sgpmwrlosB5.b1 |
D030822.5 | SGP/MWR/B6 - min/max/delta values incorrect | sgpmwrlosB6.b1 |
D040805.4 | SGP/AERI/B1 - Increased radiative uncertainty during hot summer afternoons | sgpaerich1B1.a1, sgpaerich2B1.a1 |
D040806.2 | SGP/AERI/B4 - Increased radiative uncertainty during hot summer afternoons | sgpaerich1B4.a1, sgpaerich2B4.a1 |
D040806.3 | SGP/AERI/B5 - Increased radiative uncertainty during hot summer afternoons | sgpaerich1B5.a1, sgpaerich2B5.a1 |
D040806.5 | SGP/AERI/B6 - Increased radiative uncertainty during hot summer afternoons | sgpaerich1B6.a1, sgpaerich2B6.a1 |
D050722.1 | SGP/MWR/C1 - REPROCESS - Revised Retrieval Coefficients | sgp1mwravgC1.c1, sgp5mwravgC1.c1, sgpmwrlosC1.a1, sgpmwrlosC1.b1, sgpmwrtipC1.a1, sgpqmemwrcolC1.c1 |
D050725.2 | SGP/MWR/B1 - Reprocess: Revised Retrieval Coefficients | sgp5mwravgB1.c1, sgpmwrlosB1.a1, sgpmwrlosB1.b1, sgpmwrtipB1.a1, sgpqmemwrcolB1.c1 |
D050725.3 | SGP/MWR/B4 - Reprocess: Revised Retrieval Coefficients | sgp5mwravgB4.c1, sgpmwrlosB4.a1, sgpmwrlosB4.b1, sgpmwrtipB4.a1, sgpqmemwrcolB4.c1 |
D050725.4 | SGP/MWR/B5 - Reprocess: Revised Retrieval Coefficients | sgp5mwravgB5.c1, sgpmwrlosB5.a1, sgpmwrlosB5.b1, sgpmwrtipB5.a1, sgpqmemwrcolB5.c1 |
D050725.5 | SGP/MWR/B6 - Reprocess: Revised Retrieval Coefficients | sgp5mwravgB6.c1, sgpmwrlosB6.a1, sgpmwrlosB6.b1, sgpmwrtipB6.a1, sgpqmemwrcolB6.c1 |
Start Date | Start Time | End Date | End Time |
---|---|---|---|
04/01/2002 | 0000 | 08/02/2002 | 1652 |
Subject: | SGP/MWR/B6 - High noise level, poor calibration |
DataStreams: | sgpmwrlosB6.a0, sgpmwrlosB6.a1, sgpmwrlosB6.b1 |
Description: | The data from this instrument (serial number 18) have become increasingly noisy, most likely due to a failing local oscillator. A consequence of this increased noise level has been few valid calibration scans ("tip curves") since 1 April 2002: during the period 26-31 March 2002 1496 valid tip curves were acquired, whereas only 729 were acquired during April, 387 during May, 143 during June, 243 during July. As a result, the calibration was not as well-maintained as usual. The measured brightness temperatures and retrieved precipitable water vapor and liquid water path should be regarded as suspect. The instrument was replaced with serial number 04 on 2 August 2002. |
Measurements: | sgpmwrlosB6.b1:
sgpmwrlosB6.a0:
sgpmwrlosB6.a1:
|
Start Date | Start Time | End Date | End Time |
---|---|---|---|
12/26/2001 | 2205 | 08/01/2002 | 1700 |
Subject: | SGP/MWR/B6 - Incorrect MWR warmup configuration |
DataStreams: | sgpmwrlosB6.a1, sgpmwrlosB6.b1, sgpmwrtipB6.a1 |
Description: | The local oscillator warm-up delay in the MWR configuration file was set to 720 milliseconds instead of the typical 100 milliseconds which substantially increased the duration of the observing cycle. |
Measurements: | sgpmwrtipB6.a1:
sgpmwrlosB6.b1:
sgpmwrlosB6.a1:
|
Start Date | Start Time | End Date | End Time |
---|---|---|---|
11/17/1999 | 1800 | 07/31/2002 | 2034 |
Subject: | SGP/MWR/C1 - Intermittent Negative Sky Brightness Temperatures |
DataStreams: | sgp1mwravgC1.c1, sgp5mwravgC1.c1, sgpmwrlosC1.a1, sgpmwrlosC1.b1 |
Description: | Several related and recurring problems with the SGP MWRs have been reported dating back to 1999. These problems were due to the occurrence of blackbody signals (in counts) that were half of those expected. The symptoms included noisy data (especially at Purcell), spikes in the data (especially at Vici), negative brightness temperatures, and apparent loss of serial communication between the computer and the radiometer, which results in a self-termination of the MWR program (especially at the CF). Because these all initially appeared to be hardware-related problems, the instrument mentor and SGP site operations personnel (1) repeatedly cleaned and replaced the fiber optic comm. components, (2) swapped radiometers, (3) sent radiometers back to Radiometrics for evaluation (which has not revealed any instrument problems), and (4) reconfigured the computer's operating system. Despite several attempts to isolate and correct it, the problem persisted. It became apparent that some component of the Windows98 configuration conflicted with the DOS-based MWR program or affected the serial port or the contents of the serial port buffer. This problem was finally corrected by upgrading the MWR software with a new Windows-compatible program. |
Measurements: | sgp5mwravgC1.c1:
sgpmwrlosC1.b1:
sgp1mwravgC1.c1:
sgpmwrlosC1.a1:
|
Start Date | Start Time | End Date | End Time |
---|---|---|---|
02/28/2000 | 0300 | 07/16/2002 | 2200 |
Subject: | SGP/MWR/B1 - Intermittent Negative Sky Brightness Temperatures |
DataStreams: | sgpmwrlosB1.a1, sgpmwrlosB1.b1 |
Description: | Several related and recurring problems with the SGP MWRs have been reported dating back to 1999. These problems were due to the occurrence of blackbody signals (in counts) that were half of those expected. The symptoms included noisy data (especially at Purcell), spikes in the data (especially at Vici), negative brightness temperatures, and apparent loss of serial communication between the computer and the radiometer, which results in a self-termination of the MWR program (especially at the CF). Because these all initially appeared to be hardware-related problems, the instrument mentor and SGP site operations personnel (1) repeatedly cleaned and replaced the fiber optic comm. components, (2) swapped radiometers, (3) sent radiometers back to Radiometrics for evaluation (which has not revealed any instrument problems), and (4) reconfigured the computer's operating system. Despite several attempts to isolate and correct it, the problem persisted. It became apparent that some component of the Windows98 configuration conflicted with the DOS-based MWR program or affected the serial port or the contents of the serial port buffer. This problem was finally corrected by upgrading the MWR software with a new Windows-compatible program. |
Measurements: | sgpmwrlosB1.a1:
sgpmwrlosB1.b1:
|
Start Date | Start Time | End Date | End Time |
---|---|---|---|
02/01/2000 | 2100 | 07/09/2002 | 1700 |
Subject: | SGP/MWR/B4 - Intermittent Negative Sky Brightness Temperatures |
DataStreams: | sgpmwrlosB4.a1, sgpmwrlosB4.b1 |
Description: | Several related and recurring problems with the SGP MWRs have been reported dating back to 1999. These problems were due to the occurrence of blackbody signals (in counts) that were half of those expected. The symptoms included noisy data (especially at Purcell), spikes in the data (especially at Vici), negative brightness temperatures, and apparent loss of serial communication between the computer and the radiometer, which results in a self-termination of the MWR program (especially at the CF). Because these all initially appeared to be hardware-related problems, the instrument mentor and SGP site operations personnel (1) repeatedly cleaned and replaced the fiber optic comm. components, (2) swapped radiometers, (3) sent radiometers back to Radiometrics for evaluation (which has not revealed any instrument problems), and (4) reconfigured the computer's operating system. Despite several attempts to isolate and correct it, the problem persisted. It became apparent that some component of the Windows98 configuration conflicted with the DOS-based MWR program or affected the serial port or the contents of the serial port buffer. This problem was finally corrected by upgrading the MWR software with a new Windows-compatible program. |
Measurements: | sgpmwrlosB4.b1:
sgpmwrlosB4.a1:
|
Start Date | Start Time | End Date | End Time |
---|---|---|---|
12/23/1999 | 0600 | 07/10/2002 | 1700 |
Subject: | SGP/MWR/B5 - Intermittent Negative Sky Brightness Temperatures |
DataStreams: | sgpmwrlosB5.a1, sgpmwrlosB5.b1 |
Description: | Several related and recurring problems with the SGP MWRs have been reported dating back to 1999. These problems were due to the occurrence of blackbody signals (in counts) that were half of those expected. The symptoms included noisy data (especially at Purcell), spikes in the data (especially at Vici), negative brightness temperatures, and apparent loss of serial communication between the computer and the radiometer, which results in a self-termination of the MWR program (especially at the CF). Because these all initially appeared to be hardware-related problems, the instrument mentor and SGP site operations personnel (1) repeatedly cleaned and replaced the fiber optic comm. components, (2) swapped radiometers, (3) sent radiometers back to Radiometrics for evaluation (which has not revealed any instrument problems), and (4) reconfigured the computer's operating system. Despite several attempts to isolate and correct it, the problem persisted. It became apparent that some component of the Windows98 configuration conflicted with the DOS-based MWR program or affected the serial port or the contents of the serial port buffer. This problem was finally corrected by upgrading the MWR software with a new Windows-compatible program. |
Measurements: | sgpmwrlosB5.a1:
sgpmwrlosB5.b1:
|
Start Date | Start Time | End Date | End Time |
---|---|---|---|
12/02/1999 | 1800 | 07/09/2002 | 2100 |
Subject: | SGP/MWR/B6 - Intermittent Negative Sky Brightness Temperatures |
DataStreams: | sgpmwrlosB6.a1, sgpmwrlosB6.b1 |
Description: | Several related and recurring problems with the SGP MWRs have been reported dating back to 1999. These problems were due to the occurrence of blackbody signals (in counts) that were half of those expected. The symptoms included noisy data (especially at Purcell), spikes in the data (especially at Vici), negative brightness temperatures, and apparent loss of serial communication between the computer and the radiometer, which results in a self-termination of the MWR program (especially at the CF). Because these all initially appeared to be hardware-related problems, the instrument mentor and SGP site operations personnel (1) repeatedly cleaned and replaced the fiber optic comm. components, (2) swapped radiometers, (3) sent radiometers back to Radiometrics for evaluation (which has not revealed any instrument problems), and (4) reconfigured the computer's operating system. Despite several attempts to isolate and correct it, the problem persisted. It became apparent that some component of the Windows98 configuration conflicted with the DOS-based MWR program or affected the serial port or the contents of the serial port buffer. This problem was finally corrected by upgrading the MWR software with a new Windows-compatible program. |
Measurements: | sgpmwrlosB6.b1:
sgpmwrlosB6.a1:
|
Start Date | Start Time | End Date | End Time |
---|---|---|---|
04/18/2002 | 0000 | 02/10/2003 | 2359 |
Subject: | SGP/MWR/C1 - Incorrect min and max values |
DataStreams: | sgpmwrlosC1.b1 |
Description: | The values of valid_min and valid_max applied to fields tkxc and tknd were incorrect. They should be 303 and 333, respectively. |
Measurements: | sgpmwrlosC1.b1:
|
Start Date | Start Time | End Date | End Time |
---|---|---|---|
10/28/1998 | 0000 | 01/24/2003 | 1659 |
Subject: | SGP/MWR/B1 - min/max/delta values incorrect |
DataStreams: | sgpmwrlosB1.b1 |
Description: | The values of valid_min, valid_max, and valid_delta for fields tkxc and tknd were incorrect. They should be 303, 333, and 0.5 K, respectively. |
Measurements: | sgpmwrlosB1.b1:
|
Start Date | Start Time | End Date | End Time |
---|---|---|---|
10/28/1998 | 0000 | 02/10/2003 | 2359 |
Subject: | SGP/MWR/B4 - min/max/delta values incorrect |
DataStreams: | sgpmwrlosB4.b1 |
Description: | The values of valid_min, valid_max, and valid_delta for fields tkxc and tknd were incorrect. They should be 303, 333, and 0.5 K, respectively. |
Measurements: | sgpmwrlosB4.b1:
|
Start Date | Start Time | End Date | End Time |
---|---|---|---|
01/16/1998 | 0000 | 02/10/2003 | 2359 |
Subject: | SGP/MWR/B5 - min/max/delta values incorrect |
DataStreams: | sgpmwrlosB5.b1 |
Description: | The values of valid_min, valid_max, and valid_delta for fields tkxc and tknd were incorrect. They should be 303, 333, and 0.5 K, respectively. |
Measurements: | sgpmwrlosB5.b1:
|
Start Date | Start Time | End Date | End Time |
---|---|---|---|
10/28/1998 | 0000 | 02/10/2003 | 2359 |
Subject: | SGP/MWR/B6 - min/max/delta values incorrect |
DataStreams: | sgpmwrlosB6.b1 |
Description: | The values of valid_min, valid_max, and valid_delta for fields tkxc and tknd were incorrect. They should be 303, 333, and 0.5 K, respectively. |
Measurements: | sgpmwrlosB6.b1:
|
Start Date | Start Time | End Date | End Time |
---|---|---|---|
12/15/1998 | 1707 | 10/12/2003 | 2359 |
Subject: | SGP/AERI/B1 - Increased radiative uncertainty during hot summer afternoons |
DataStreams: | sgpaerich1B1.a1, sgpaerich2B1.a1 |
Description: | The ambient temperature of the AERI enclosures at the boundary facilities often exceeded 308 K during hot summer afternoons. This threshold marked the maximum end of the "acceptable" range of temperatures that the ambient blackbody should maintain. The issue is that if the hot blackbody and ambient blackbody temperatures are too close together, then the radiative calibration becomes more uncertain. It should be noted that the hot blackbody's temperature is maintained at roughly 333 K. Using the calibration equation, an uncertainty analysis was performed to see how much "additional" uncertainty resulted in the AERI observations when the ambient temperature was between 308-315 K (315 K was the maximum temperature that the ambient blackbody reached during the summer). The analysis compared the radiative uncertainties from the Hillsboro (B1) AERI (chosen at random) with the AERI-01 at the SGP/CF over a 5-year period. Plot1 (below) shows the time-series of ambient blackbody temperatures for the two instruments, along with histograms to show the distribution of the temperatures. The boundary facility instrument did suffer from higher temperatures in the summer time periods. Plot2 (bleow) shows the relative radiative uncertainty for each instrument. The CF instrument has a maximum radiative uncertainty of around 0.18% during the summer, while the BF instrument's maximum radiative uncertainty is about 0.25%. This plot demonstrates that the radiative uncertainty is significantly larger for the BF instrument in the summer relative to the CF instrument. However, the absolute radiative accuracy for the AERI is specified to be better than 1% of the ambient radiance, and both the CF and the BF AERIs are well within this uncertainty. In short, there is significantly higher radiative uncertainty in the BF AERIs during the hot summer afternoons, but the uncertainty is well within the specified accuracy of the instrument. plot1: aeri_abb_temp.lamont_hillsboro.png plot2: aeri_relative_error.lamont_hillsboro.png |
Measurements: | sgpaerich1B1.a1:
sgpaerich2B1.a1:
|
Start Date | Start Time | End Date | End Time |
---|---|---|---|
12/15/1998 | 2002 | 06/08/2003 | 2359 |
Subject: | SGP/AERI/B4 - Increased radiative uncertainty during hot summer afternoons |
DataStreams: | sgpaerich1B4.a1, sgpaerich2B4.a1 |
Description: | The ambient temperature of the AERI enclosures at the boundary facilities often exceeded 308 K during hot summer afternoons. This threshold marked the maximum end of the "acceptable" range of temperatures that the ambient blackbody should maintain. The issue is that if the hot blackbody and ambient blackbody temperatures are too close together, then the radiative calibration becomes more uncertain. It should be noted that the hot blackbody's temperature is maintained at roughly 333 K. Using the calibration equation, an uncertainty analysis was performed to see how much "additional" uncertainty resulted in the AERI observations when the ambient temperature was between 308-315 K (315 K was the maximum temperature that the ambient blackbody reached during the summer). The analysis compared the radiative uncertainties from the Hillsboro (B1) AERI (chosen at random) with the AERI-01 at the SGP/CF over a 5-year period. Plot1 (below) shows the time-series of ambient blackbody temperatures for the two instruments, along with histograms to show the distribution of the temperatures. The boundary facility instrument did suffer from higher temperatures in the summer time periods. Plot2 (bleow) shows the relative radiative uncertainty for each instrument. The CF instrument has a maximum radiative uncertainty of around 0.18% during the summer, while the BF instrument's maximum radiative uncertainty is about 0.25%. This plot demonstrates that the radiative uncertainty is significantly larger for the BF instrument in the summer relative to the CF instrument. However, the absolute radiative accuracy for the AERI is specified to be better than 1% of the ambient radiance, and both the CF and the BF AERIs are well within this uncertainty. In short, there is significantly higher radiative uncertainty in the BF AERIs during the hot summer afternoons, but the uncertainty is well within the specified accuracy of the instrument. plot1: aeri_abb_temp.lamont_hillsboro.png plot2: aeri_relative_error.lamont_hillsboro.png |
Measurements: | sgpaerich2B4.a1:
sgpaerich1B4.a1:
|
Start Date | Start Time | End Date | End Time |
---|---|---|---|
12/15/1998 | 0008 | 10/12/2003 | 2359 |
Subject: | SGP/AERI/B5 - Increased radiative uncertainty during hot summer afternoons |
DataStreams: | sgpaerich1B5.a1, sgpaerich2B5.a1 |
Description: | The ambient temperature of the AERI enclosures at the boundary facilities often exceeded 308 K during hot summer afternoons. This threshold marked the maximum end of the "acceptable" range of temperatures that the ambient blackbody should maintain. The issue is that if the hot blackbody and ambient blackbody temperatures are too close together, then the radiative calibration becomes more uncertain. It should be noted that the hot blackbody's temperature is maintained at roughly 333 K. Using the calibration equation, an uncertainty analysis was performed to see how much "additional" uncertainty resulted in the AERI observations when the ambient temperature was between 308-315 K (315 K was the maximum temperature that the ambient blackbody reached during the summer). The analysis compared the radiative uncertainties from the Hillsboro (B1) AERI (chosen at random) with the AERI-01 at the SGP/CF over a 5-year period. Plot1 (below) shows the time-series of ambient blackbody temperatures for the two instruments, along with histograms to show the distribution of the temperatures. The boundary facility instrument did suffer from higher temperatures in the summer time periods. Plot2 (bleow) shows the relative radiative uncertainty for each instrument. The CF instrument has a maximum radiative uncertainty of around 0.18% during the summer, while the BF instrument's maximum radiative uncertainty is about 0.25%. This plot demonstrates that the radiative uncertainty is significantly larger for the BF instrument in the summer relative to the CF instrument. However, the absolute radiative accuracy for the AERI is specified to be better than 1% of the ambient radiance, and both the CF and the BF AERIs are well within this uncertainty. In short, there is significantly higher radiative uncertainty in the BF AERIs during the hot summer afternoons, but the uncertainty is well within the specified accuracy of the instrument. plot1: aeri_abb_temp.lamont_hillsboro.png plot2: aeri_relative_error.lamont_hillsboro.png |
Measurements: | sgpaerich2B5.a1:
sgpaerich1B5.a1:
|
Start Date | Start Time | End Date | End Time |
---|---|---|---|
11/17/1998 | 2310 | 10/12/2003 | 2359 |
Subject: | SGP/AERI/B6 - Increased radiative uncertainty during hot summer afternoons |
DataStreams: | sgpaerich1B6.a1, sgpaerich2B6.a1 |
Description: | The ambient temperature of the AERI enclosures at the boundary facilities often exceeded 308 K during hot summer afternoons. This threshold marked the maximum end of the "acceptable" range of temperatures that the ambient blackbody should maintain. The issue is that if the hot blackbody and ambient blackbody temperatures are too close together, then the radiative calibration becomes more uncertain. It should be noted that the hot blackbody's temperature is maintained at roughly 333 K. Using the calibration equation, an uncertainty analysis was performed to see how much "additional" uncertainty resulted in the AERI observations when the ambient temperature was between 308-315 K (315 K was the maximum temperature that the ambient blackbody reached during the summer). The analysis compared the radiative uncertainties from the Hillsboro (B1) AERI (chosen at random) with the AERI-01 at the SGP/CF over a 5-year period. Plot1 (below) shows the time-series of ambient blackbody temperatures for the two instruments, along with histograms to show the distribution of the temperatures. The boundary facility instrument did suffer from higher temperatures in the summer time periods. Plot2 (bleow) shows the relative radiative uncertainty for each instrument. The CF instrument has a maximum radiative uncertainty of around 0.18% during the summer, while the BF instrument's maximum radiative uncertainty is about 0.25%. This plot demonstrates that the radiative uncertainty is significantly larger for the BF instrument in the summer relative to the CF instrument. However, the absolute radiative accuracy for the AERI is specified to be better than 1% of the ambient radiance, and both the CF and the BF AERIs are well within this uncertainty. In short, there is significantly higher radiative uncertainty in the BF AERIs during the hot summer afternoons, but the uncertainty is well within the specified accuracy of the instrument. plot1: aeri_abb_temp.lamont_hillsboro.png plot2: aeri_relative_error.lamont_hillsboro.png |
Measurements: | sgpaerich1B6.a1:
sgpaerich2B6.a1:
|
Start Date | Start Time | End Date | End Time |
---|---|---|---|
04/16/2002 | 2000 | 06/28/2005 | 2300 |
Subject: | SGP/MWR/C1 - REPROCESS - Revised Retrieval Coefficients |
DataStreams: | sgp1mwravgC1.c1, sgp5mwravgC1.c1, sgpmwrlosC1.a1, sgpmwrlosC1.b1, sgpmwrtipC1.a1, sgpqmemwrcolC1.c1 |
Description: | IN THE BEGINNING (June 1992), the retrieval coefficients used to derive the precipitable water vapor (PWV) and liquid water path (LWP) from the MWR brightness temperatures were based on the Liebe and Layton (1987) water vapor and oxygen absorption model and the Grant (1957) liquid water absorption model. Following the SHEBA experience, revised retrievals based on the more recent Rosenkranz (1998) water vapor and oxygen absorption models and the Liebe (1991) liquid waer absorption model were developed. The Rosenkranz water vapor absorption model resulted a 2 percent increase in PWV relative to the earlier Liebe and Layton model. The Liebe liquid water absorption model decreased the LWP by 10% relative to the Grant model. However, the increased oxygen absorption caused a 0.02-0.03 mm (20-30 g/m2) reduction in LWP, which was particularly significant for low LWP conditions (i.e. thin clouds encountered at SHEBA). Recently, it has been shown (Liljegren, Boukabara, Cady-Pereira, and Clough, TGARS v. 43, pp 1102-1108, 2005) that the half-width of the 22 GHz water vapor line from the HITRAN compilation, which is 5 percent smaller than the Liebe and Dillon (1969) half-width used in Rosenkranz (1998), provided a better fit to the microwave brightness temperature measurements at 5 frequencies in the range 22-30 GHz, and yielded more accurate retrievals. Accordingly, revised MWR retrieval coefficients have been developed using MONORTM, which utilizes the HITRAN compilation for its spectroscopic parameters. These new retrievals provide 3 percent less PWV and 2.6 percent greater LWP than the previous retrievals based on Rosenkranz (1998). Although the MWR data will be reprocessed to apply the new monortm-based retrievals, for most purposes it will be sufficient to correct the data using the following factors: PWV_MONORTM = 0.9695 * PWV_ROSENKRANZ LWP_MONORTM = 1.026 * LWP_ROSENKRANZ The Rosenkranz-based retrieval coefficients became active as follows (BCR 456): SGP/C1 (Lamont) 4/16/2002, 2000 SGP/B1 (Hillsboro) 4/12/2002, 1600 SGP/B4 (Vici) 4/15/2002, 2300 SGP/B5 (Morris) 4/15/2002, 2300 SGP/B6 (Purcell) 4/16/2002, 2200 SGP/E14(Lamont) 4/16/2002, 0000 NSA/C1 (Barrow) 4/25/2002, 1900 NSA/C2 (Atqasuk) 4/18/2002, 1700 TWP/C1 (Manus) 5/04/2002, 0200 TWP/C2 (Nauru) 4/27/2002, 0600 TWP/C3 (Darwin) inception The MONORTM-based retrieval coefficients became active as follows (BCR 984): SGP/C1 (Lamont) 6/28/2005, 2300 SGP/B1 (Hillsboro) 6/24/2005, 2100 SGP/B4 (Vici) 6/24/2005, 2100 SGP/B5 (Morris) 6/24/2005, 2100 SGP/B6 (Purcell) 6/24/2005, 1942 SGP/E14(Lamont) 6/28/2005, 2300 NSA/C1 (Barrow) 6/29/2005, 0000 NSA/C2 (Atqasuk) 6/29/2005, 0000 TWP/C1 (Manus) 6/30/2005, 2100 TWP/C2 (Nauru) 6/30/2005, 2100 TWP/C3 (Darwin) 6/30/2005, 2100 PYE/M1 (Pt. Reyes) 4/08/2005, 1900** ** At Pt. Reyes, the original retrieval coefficients implemented in March 2005 were based on a version of the Rosenkranz model that had been modified to use the HITRAN half-width at 22 GHz and to be consistent with the water vapor continuum in MONORTM. These retrievals yield nearly identical results to the MONORTM retrievals. Therefore the Pt. Reyes data prior to 4/08/2005 may not require reprocessing. |
Measurements: | sgpmwrtipC1.a1:
sgp5mwravgC1.c1:
sgpmwrlosC1.b1:
sgp1mwravgC1.c1:
sgpqmemwrcolC1.c1:
sgpmwrlosC1.a1:
|
Start Date | Start Time | End Date | End Time |
---|---|---|---|
04/12/2002 | 1600 | 06/24/2005 | 2100 |
Subject: | SGP/MWR/B1 - Reprocess: Revised Retrieval Coefficients |
DataStreams: | sgp5mwravgB1.c1, sgpmwrlosB1.a1, sgpmwrlosB1.b1, sgpmwrtipB1.a1, sgpqmemwrcolB1.c1 |
Description: | IN THE BEGINNING (June 1992), the retrieval coefficients used to derive the precipitable water vapor (PWV) and liquid water path (LWP) from the MWR brightness temperatures were based on the Liebe and Layton (1987) water vapor and oxygen absorption model and the Grant (1957) liquid water absorption model. Following the SHEBA experience, revised retrievals based on the more recent Rosenkranz (1998) water vapor and oxygen absorption models and the Liebe (1991) liquid waer absorption model were developed. The Rosenkranz water vapor absorption model resulted a 2 percent increase in PWV relative to the earlier Liebe and Layton model. The Liebe liquid water absorption model decreased the LWP by 10% relative to the Grant model. However, the increased oxygen absorption caused a 0.02-0.03 mm (20-30 g/m2) reduction in LWP, which was particularly significant for low LWP conditions (i.e. thin clouds encountered at SHEBA). Recently, it has been shown (Liljegren, Boukabara, Cady-Pereira, and Clough, TGARS v. 43, pp 1102-1108, 2005) that the half-width of the 22 GHz water vapor line from the HITRAN compilation, which is 5 percent smaller than the Liebe and Dillon (1969) half-width used in Rosenkranz (1998), provided a better fit to the microwave brightness temperature measurements at 5 frequencies in the range 22-30 GHz, and yielded more accurate retrievals. Accordingly, revised MWR retrieval coefficients have been developed using MONORTM, which utilizes the HITRAN compilation for its spectroscopic parameters. These new retrievals provide 3 percent less PWV and 2.6 percent greater LWP than the previous retrievals based on Rosenkranz (1998). Although the MWR data will be reprocessed to apply the new monortm-based retrievals, for most purposes it will be sufficient to correct the data using the following factors: PWV_MONORTM = 0.9695 * PWV_ROSENKRANZ LWP_MONORTM = 1.026 * LWP_ROSENKRANZ The Rosenkranz-based retrieval coefficients became active at SGP.B1 20020412.1600. The MONORTM-based retrieval coefficients became active at SGP.B1 20050624.2100. Note: a reprocessing effort is already underway to apply the Rosenkranz-based retrieval coefficients to all MWR prior to April 2002. An additional reprocessing task will be undertaken to apply the MONORTM retrieval to all MWR data when the first is completed. Read reprocessing comments in the netcdf file header carefully to ensure you are aware which retrieval is in play. |
Measurements: | sgpmwrlosB1.a1:
sgpmwrlosB1.b1:
sgp5mwravgB1.c1:
sgpmwrtipB1.a1:
sgpqmemwrcolB1.c1:
|
Start Date | Start Time | End Date | End Time |
---|---|---|---|
04/15/2002 | 2300 | 06/24/2005 | 2100 |
Subject: | SGP/MWR/B4 - Reprocess: Revised Retrieval Coefficients |
DataStreams: | sgp5mwravgB4.c1, sgpmwrlosB4.a1, sgpmwrlosB4.b1, sgpmwrtipB4.a1, sgpqmemwrcolB4.c1 |
Description: | IN THE BEGINNING (June 1992), the retrieval coefficients used to derive the precipitable water vapor (PWV) and liquid water path (LWP) from the MWR brightness temperatures were based on the Liebe and Layton (1987) water vapor and oxygen absorption model and the Grant (1957) liquid water absorption model. Following the SHEBA experience, revised retrievals based on the more recent Rosenkranz (1998) water vapor and oxygen absorption models and the Liebe (1991) liquid waer absorption model were developed. The Rosenkranz water vapor absorption model resulted a 2 percent increase in PWV relative to the earlier Liebe and Layton model. The Liebe liquid water absorption model decreased the LWP by 10% relative to the Grant model. However, the increased oxygen absorption caused a 0.02-0.03 mm (20-30 g/m2) reduction in LWP, which was particularly significant for low LWP conditions (i.e. thin clouds encountered at SHEBA). Recently, it has been shown (Liljegren, Boukabara, Cady-Pereira, and Clough, TGARS v. 43, pp 1102-1108, 2005) that the half-width of the 22 GHz water vapor line from the HITRAN compilation, which is 5 percent smaller than the Liebe and Dillon (1969) half-width used in Rosenkranz (1998), provided a better fit to the microwave brightness temperature measurements at 5 frequencies in the range 22-30 GHz, and yielded more accurate retrievals. Accordingly, revised MWR retrieval coefficients have been developed using MONORTM, which utilizes the HITRAN compilation for its spectroscopic parameters. These new retrievals provide 3 percent less PWV and 2.6 percent greater LWP than the previous retrievals based on Rosenkranz (1998). Although the MWR data will be reprocessed to apply the new monortm-based retrievals, for most purposes it will be sufficient to correct the data using the following factors: PWV_MONORTM = 0.9695 * PWV_ROSENKRANZ LWP_MONORTM = 1.026 * LWP_ROSENKRANZ The Rosenkranz-based retrieval coefficients became active at SGP.B4 20020415.2300. The MONORTM-based retrieval coefficients became active at SGP.B4 20050624.2100. Note: a reprocessing effort is already underway to apply the Rosenkranz-based retrieval coefficients to all MWR prior to April 2002. An additional reprocessing task will be undertaken to apply the MONORTM retrieval to all MWR data when the first is completed. Read reprocessing comments in the netcdf file header carefully to ensure you are aware which retrieval is in play. |
Measurements: | sgpmwrlosB4.b1:
sgpmwrtipB4.a1:
sgpqmemwrcolB4.c1:
sgp5mwravgB4.c1:
sgpmwrlosB4.a1:
|
Start Date | Start Time | End Date | End Time |
---|---|---|---|
04/15/2002 | 2300 | 06/24/2005 | 2100 |
Subject: | SGP/MWR/B5 - Reprocess: Revised Retrieval Coefficients |
DataStreams: | sgp5mwravgB5.c1, sgpmwrlosB5.a1, sgpmwrlosB5.b1, sgpmwrtipB5.a1, sgpqmemwrcolB5.c1 |
Description: | IN THE BEGINNING (June 1992), the retrieval coefficients used to derive the precipitable water vapor (PWV) and liquid water path (LWP) from the MWR brightness temperatures were based on the Liebe and Layton (1987) water vapor and oxygen absorption model and the Grant (1957) liquid water absorption model. Following the SHEBA experience, revised retrievals based on the more recent Rosenkranz (1998) water vapor and oxygen absorption models and the Liebe (1991) liquid waer absorption model were developed. The Rosenkranz water vapor absorption model resulted a 2 percent increase in PWV relative to the earlier Liebe and Layton model. The Liebe liquid water absorption model decreased the LWP by 10% relative to the Grant model. However, the increased oxygen absorption caused a 0.02-0.03 mm (20-30 g/m2) reduction in LWP, which was particularly significant for low LWP conditions (i.e. thin clouds encountered at SHEBA). Recently, it has been shown (Liljegren, Boukabara, Cady-Pereira, and Clough, TGARS v. 43, pp 1102-1108, 2005) that the half-width of the 22 GHz water vapor line from the HITRAN compilation, which is 5 percent smaller than the Liebe and Dillon (1969) half-width used in Rosenkranz (1998), provided a better fit to the microwave brightness temperature measurements at 5 frequencies in the range 22-30 GHz, and yielded more accurate retrievals. Accordingly, revised MWR retrieval coefficients have been developed using MONORTM, which utilizes the HITRAN compilation for its spectroscopic parameters. These new retrievals provide 3 percent less PWV and 2.6 percent greater LWP than the previous retrievals based on Rosenkranz (1998). Although the MWR data will be reprocessed to apply the new monortm-based retrievals, for most purposes it will be sufficient to correct the data using the following factors: PWV_MONORTM = 0.9695 * PWV_ROSENKRANZ LWP_MONORTM = 1.026 * LWP_ROSENKRANZ The Rosenkranz-based retrieval coefficients became active at SGP.B5 20020415.2300. The MONORTM-based retrieval coefficients became active at SGP.B5 20050624.2100. Note: a reprocessing effort is already underway to apply the Rosenkranz-based retrieval coefficients to all MWR prior to April 2002. An additional reprocessing task will be undertaken to apply the MONORTM retrieval to all MWR data when the first is completed. Read reprocessing comments in the netcdf file header carefully to ensure you are aware which retrieval is in play. |
Measurements: | sgpmwrlosB5.a1:
sgpmwrtipB5.a1:
sgpqmemwrcolB5.c1:
sgp5mwravgB5.c1:
sgpmwrlosB5.b1:
|
Start Date | Start Time | End Date | End Time |
---|---|---|---|
04/16/2002 | 2200 | 06/24/2005 | 1942 |
Subject: | SGP/MWR/B6 - Reprocess: Revised Retrieval Coefficients |
DataStreams: | sgp5mwravgB6.c1, sgpmwrlosB6.a1, sgpmwrlosB6.b1, sgpmwrtipB6.a1, sgpqmemwrcolB6.c1 |
Description: | IN THE BEGINNING (June 1992), the retrieval coefficients used to derive the precipitable water vapor (PWV) and liquid water path (LWP) from the MWR brightness temperatures were based on the Liebe and Layton (1987) water vapor and oxygen absorption model and the Grant (1957) liquid water absorption model. Following the SHEBA experience, revised retrievals based on the more recent Rosenkranz (1998) water vapor and oxygen absorption models and the Liebe (1991) liquid waer absorption model were developed. The Rosenkranz water vapor absorption model resulted a 2 percent increase in PWV relative to the earlier Liebe and Layton model. The Liebe liquid water absorption model decreased the LWP by 10% relative to the Grant model. However, the increased oxygen absorption caused a 0.02-0.03 mm (20-30 g/m2) reduction in LWP, which was particularly significant for low LWP conditions (i.e. thin clouds encountered at SHEBA). Recently, it has been shown (Liljegren, Boukabara, Cady-Pereira, and Clough, TGARS v. 43, pp 1102-1108, 2005) that the half-width of the 22 GHz water vapor line from the HITRAN compilation, which is 5 percent smaller than the Liebe and Dillon (1969) half-width used in Rosenkranz (1998), provided a better fit to the microwave brightness temperature measurements at 5 frequencies in the range 22-30 GHz, and yielded more accurate retrievals. Accordingly, revised MWR retrieval coefficients have been developed using MONORTM, which utilizes the HITRAN compilation for its spectroscopic parameters. These new retrievals provide 3 percent less PWV and 2.6 percent greater LWP than the previous retrievals based on Rosenkranz (1998). Although the MWR data will be reprocessed to apply the new monortm-based retrievals, for most purposes it will be sufficient to correct the data using the following factors: PWV_MONORTM = 0.9695 * PWV_ROSENKRANZ LWP_MONORTM = 1.026 * LWP_ROSENKRANZ The Rosenkranz-based retrieval coefficients became active at SGP.B6 20020416.2200. The MONORTM-based retrieval coefficients became active at SGP.B6 20050624.1942. Note: a reprocessing effort is already underway to apply the Rosenkranz-based retrieval coefficients to all MWR prior to April 2002. An additional reprocessing task will be undertaken to apply the MONORTM retrieval to all MWR data when the first is completed. Read reprocessing comments in the netcdf file header carefully to ensure you are aware which retrieval is in play. |
Measurements: | sgpmwrtipB6.a1:
sgp5mwravgB6.c1:
sgpmwrlosB6.b1:
sgpqmemwrcolB6.c1:
sgpmwrlosB6.a1:
|