DQR ID | Subject | Data Streams Affected |
---|---|---|
D010201.1 | NSA/MWR/C1 - Temperature Stabilization of Noise Diode Impaired | nsa5mwravgC1.c1, nsamwrlosC1.a1, nsamwrlosC1.b1 |
D010216.2 | NSA/MWR/C1 - NSA Barrow MWR down due to PC Virus | nsamwrlosC1.a1, nsamwrlosC1.b1, nsamwrtipC1.a1, nsamwrtipC1.b1 |
D010308.1 | NSA/MWR/C2 - Elevated sky brightness temperatures | nsamwrlosC2.b1, nsamwrtipC2.a1 |
D010504.2 | NSA/MWR/C2 - Missing data | nsamwrlosC2.b1, nsamwrtipC2.a1 |
D010504.4 | NSA/MWR/C1 - Reprocess: calibration change | nsamwrlosC1.a1, nsamwrlosC1.b1, nsamwrtipC1.a1 |
D020122.1 | NSA/MWR/C1 - Reprocess: wrong calibration | nsamwrlosC1.a1, nsamwrlosC1.b1 |
D020824.4 | NSA/MWR/C2 - Instrument Maintenance | nsamwrlosC2.b1 |
D030312.6 | SGP/MWR/C1 - Intermittent Negative Sky Brightness Temperatures | nsamwrlosC1.a1, nsamwrlosC1.b1 |
D030312.7 | NSA/MWR/C2 - Intermittent Negative Sky Brightness Temperatures | nsamwrlosC2.b1 |
D030822.7 | NSA/MWR/C1 - min/max/delta values incorrect | nsamwrlosC1.b1 |
D050725.8 | NSA/MWR/C2 - Reprocessed: Revised Retrieval Coefficients | nsamwrlosC2.b1, nsamwrtipC2.a1 |
Start Date | Start Time | End Date | End Time |
---|---|---|---|
01/17/2001 | 0600 | 01/22/2001 | 2145 |
Subject: | NSA/MWR/C1 - Temperature Stabilization of Noise Diode Impaired |
DataStreams: | nsa5mwravgC1.c1, nsamwrlosC1.a1, nsamwrlosC1.b1 |
Description: | On 1/17 we had a big spike in the data and lost temperature stabilization. The instrument had problems maintaining the Noise Diode (ND) temperature since. At ambient temperatures under about -20 C the ND was not maintaining the set temperature of 30 C. This problem was reported in P010122.1. Fred Solheim recommended on 1/22 that we powercycle the instrument as it looked like the instrument CPU had lost the temperature reference. So we powercycled the instrument on 1/22 @ 20:30 and lost all comumnication to it; after a second powercycling the instrument came back on line and the temperature stabilized quickly (within a couple of minutes) to the set temperature (30 C) Fred Solheim reported after the system was restored: "I've never seen this behavior before. I don't think it was due to the RF deck physically hanging temperature, because the recorded temp dropped about 30 C in one observation cycle. If this happens again, send the MWR down along with data files for us to look at." Data collected in the periode 1/17/2001 6:00 to 1/22/2001 21:45 are questionable since it is uncertain whether the temperature really was unstable and what really caused the problem. |
Measurements: | nsamwrlosC1.a1:
nsa5mwravgC1.c1:
nsamwrlosC1.b1:
|
Start Date | Start Time | End Date | End Time |
---|---|---|---|
12/22/2000 | 2300 | 01/09/2001 | 2230 |
Subject: | NSA/MWR/C1 - NSA Barrow MWR down due to PC Virus |
DataStreams: | nsamwrlosC1.a1, nsamwrlosC1.b1, nsamwrtipC1.a1, nsamwrtipC1.b1 |
Description: | On 12/22 at 23:00 the PC communication hung. Before operators returned to work after the holidays on 12/26, the virus W32.kriz triggered on 12/25 at 1:43 GMT. This virus wiped out large amount of files, hereunder the data files from the period 12/22 23:00 - 12/25 01:00 and OS system files. The fixed PC was re-installed on 1/5, due issues with using serial ports under DOS comunication with instrument was not restored until 1/9 @ 22:30 GMT |
Measurements: | nsamwrlosC1.a1:
nsamwrtipC1.b1:
nsamwrlosC1.b1:
nsamwrtipC1.a1:
|
Start Date | Start Time | End Date | End Time |
---|---|---|---|
04/16/2000 | 0554 | 05/11/2000 | 0100 |
02/16/2001 | 1900 | 02/26/2001 | 0020 |
Subject: | NSA/MWR/C2 - Elevated sky brightness temperatures |
DataStreams: | nsamwrlosC2.b1, nsamwrtipC2.a1 |
Description: | The MWR was providing unreasonable values of sky brightness temperatures and values of precipitable water vapor and liquid water path that were about 10 times larger than expected. The problem was corrected when the instrument was power-cycled. The cause of the problem is unknown. |
Measurements: | nsamwrlosC2.b1:
nsamwrtipC2.a1:
|
Start Date | Start Time | End Date | End Time |
---|---|---|---|
10/26/1999 | 0003 | 11/02/1999 | 0008 |
11/09/1999 | 0004 | 12/27/1999 | 0008 |
12/28/1999 | 0004 | 01/08/2000 | 0008 |
01/11/2000 | 0004 | 01/20/2000 | 0428 |
03/11/2000 | 0218 | 03/22/2000 | 0449 |
04/16/2000 | 1536 | 04/18/2000 | 0540 |
06/09/2000 | 0605 | 06/12/2000 | 0408 |
09/28/2000 | 0036 | 09/30/2000 | 0132 |
02/03/2001 | 0208 | 02/05/2001 | 0014 |
06/23/2001 | 0000 | 06/25/2001 | 1820 |
07/01/2001 | 2000 | 07/04/2001 | 1745 |
07/15/2001 | 1800 | 07/17/2001 | 1650 |
11/17/2001 | 0300 | 11/28/2001 | 2332 |
01/21/2002 | 2221 | 01/23/2002 | 0417 |
04/02/2002 | 0000 | 04/03/2002 | 0151 |
04/15/2002 | 2324 | 04/17/2002 | 0108 |
07/21/2002 | 1800 | 07/23/2002 | 0448 |
12/18/2002 | 2218 | 01/28/2003 | 2115 |
02/17/2003 | 1842 | 02/25/2003 | 2044 |
09/22/2005 | 1932 | 10/01/2005 | 1700 |
Subject: | NSA/MWR/C2 - Missing data |
DataStreams: | nsamwrlosC2.b1, nsamwrtipC2.a1 |
Description: | Data are missing and unrecoverable. |
Measurements: | nsamwrlosC2.b1:
nsamwrtipC2.a1:
|
Start Date | Start Time | End Date | End Time |
---|---|---|---|
01/31/2001 | 0900 | 02/06/2001 | 0237 |
Subject: | NSA/MWR/C1 - Reprocess: calibration change |
DataStreams: | nsamwrlosC1.a1, nsamwrlosC1.b1, nsamwrtipC1.a1 |
Description: | The computer was replaced but not configured correctly for the MWR. |
Measurements: | nsamwrlosC1.a1:
nsamwrlosC1.b1:
nsamwrtipC1.a1:
|
Start Date | Start Time | End Date | End Time |
---|---|---|---|
09/27/2001 | 1900 | 09/29/2001 | 1000 |
Subject: | NSA/MWR/C1 - Reprocess: wrong calibration |
DataStreams: | nsamwrlosC1.a1, nsamwrlosC1.b1 |
Description: | Moisture was found inside the lens of the MWR. Removal of the moisture caused a significant change in the calibration, especially in the 23.8 GHz channel. The calibration was updated automatically. |
Measurements: | nsamwrlosC1.a1:
nsamwrlosC1.b1:
|
Start Date | Start Time | End Date | End Time |
---|---|---|---|
06/18/2001 | 0200 | 06/18/2001 | 0300 |
Subject: | NSA/MWR/C2 - Instrument Maintenance |
DataStreams: | nsamwrlosC2.b1 |
Description: | Exchange of winter cover caused data corruption. |
Measurements: | nsamwrlosC2.b1:
|
Start Date | Start Time | End Date | End Time |
---|---|---|---|
11/07/1999 | 1800 | 09/16/2002 | 1820 |
Subject: | SGP/MWR/C1 - Intermittent Negative Sky Brightness Temperatures |
DataStreams: | nsamwrlosC1.a1, nsamwrlosC1.b1 |
Description: | Several related and recurring problems with the 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, spikes in the data, 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. Because these all initially appeared to be hardware-related problems, the instrument mentor and 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 did 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: | nsamwrlosC1.a1:
nsamwrlosC1.b1:
|
Start Date | Start Time | End Date | End Time |
---|---|---|---|
02/15/2000 | 0600 | 09/16/2002 | 1900 |
Subject: | NSA/MWR/C2 - Intermittent Negative Sky Brightness Temperatures |
DataStreams: | nsamwrlosC2.b1 |
Description: | Several related and recurring problems with the 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, spikes in the data, 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. Because these all initially appeared to be hardware-related problems, the instrument mentor and 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 did 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: | nsamwrlosC2.b1:
|
Start Date | Start Time | End Date | End Time |
---|---|---|---|
01/02/1998 | 0000 | 02/08/2003 | 2359 |
Subject: | NSA/MWR/C1 - min/max/delta values incorrect |
DataStreams: | nsamwrlosC1.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: | nsamwrlosC1.b1:
|
Start Date | Start Time | End Date | End Time |
---|---|---|---|
10/18/1999 | 0000 | 06/29/2005 | 0000 |
Subject: | NSA/MWR/C2 - Reprocessed: Revised Retrieval Coefficients |
DataStreams: | nsamwrlosC2.b1, nsamwrtipC2.a1 |
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 water 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). The Rosenkranz-based retrieval coefficients became active at NSA.C2 20020418.1700. The MONORTM-based retrieval coefficients became active at NSA.C2 20050629.0000. Note: The NSA.C2 MWRLOS data for 19991018-20050630 have been reprocessed to apply the MONORTM-based retrievals for all time. The reprocessed data were archived in March 2007. The TIP data have not been reprocessed. |
Measurements: | nsamwrlosC2.b1:
nsamwrtipC2.a1:
|