| DQR ID | Subject | Data Streams Affected |
|---|---|---|
| D030515.3 | NSA/MWR/C1 - no air temperature signal | nsamwrC1.00, nsamwrlosC1.b1, nsamwrtipC1.a1 |
| D040225.5 | NSA/MWR/C1 - power supply failure | nsamwrlosC1.a1, nsamwrlosC1.b1, nsamwrtipC1.a1 |
| D050725.7 | NSA/MWR/C1 - Reprocess: Revised Calibration Coefficients | nsamwrlosC1.a1, nsamwrlosC1.b1, nsamwrtipC1.a1, nsa5mwravgC1.c1, nsaqmemwrcolC1.c1 |
| D050928.3 | NSA/MWR/C1 - New software version (4.15) installed | nsamwrlosC1.b1, nsamwrtipC1.a1 |
| Start Date | Start Time | End Date | End Time |
|---|---|---|---|
| 05/13/2003 | 1906 | 01/15/2005 | 0054 |
| Subject: | NSA/MWR/C1 - no air temperature signal |
| DataStreams: | nsamwrC1.00, nsamwrlosC1.b1, nsamwrtipC1.a1 |
| Description: | When the new blower was upgraded by Radiometrics and reinstalled on the MWR, the air temperature sensor failed to properly report. It was determined that the wires carrying the signal to the analog board did not conform to the standard expected by the upgraded blower. The problem was corrected by changing the wiring and modifying the MWR software to read the signal from the appropriate corresponding channel. |
| Measurements: | nsamwrC1.00:
nsamwrlosC1.b1:
nsamwrtipC1.a1:
|
| Start Date | Start Time | End Date | End Time |
|---|---|---|---|
| 02/10/2004 | 0847 | 02/17/2004 | 0156 |
| Subject: | NSA/MWR/C1 - power supply failure |
| DataStreams: | nsamwrlosC1.a1, nsamwrlosC1.b1, nsamwrtipC1.a1 |
| Description: | The MWR failed due to infiltration of blowing snow which damaged the electronics. The digital and analog boards were replaced by new boards supplied by Radiometrics and the power supply was replaced by the unit from the spare MWR. |
| Measurements: | nsamwrlosC1.a1:
nsamwrlosC1.b1:
nsamwrtipC1.a1:
|
| Start Date | Start Time | End Date | End Time |
|---|---|---|---|
| 04/25/2002 | 1900 | 06/29/2005 | 0000 |
| Subject: | NSA/MWR/C1 - Reprocess: Revised Calibration Coefficients |
| DataStreams: | nsamwrlosC1.a1, nsamwrlosC1.b1, nsamwrtipC1.a1, nsa5mwravgC1.c1, nsaqmemwrcolC1.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 NSA.C1 20020425.1900. The MONORTM-based retrieval coefficients became active at NSA.C1 20050629.0000. 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: | nsamwrlosC1.a1:
nsa5mwravgC1.c1:
nsaqmemwrcolC1.c1:
nsamwrlosC1.b1:
nsamwrtipC1.a1:
|
| Start Date | Start Time | End Date | End Time |
|---|---|---|---|
| 09/16/2002 | 1820 | 09/15/2005 | 1702 |
| Subject: | NSA/MWR/C1 - New software version (4.15) installed |
| DataStreams: | nsamwrlosC1.b1, nsamwrtipC1.a1 |
| Description: | A problem began with the installation of MWR.EXE version 4.12 in September 2002. The software had been upgraded from a "DOS" to a "Windows"-compiled program to address an earlier problem. The software upgrade corrected the earlier problem but introduced a new one that caused line-of-sight observing cycles to be skipped, a 15% reduction in the number of tip curves, and saturation of CPU usage. Software versions 4.13 and 4.14 also produced these problems. The new MWR software version (4.15) was installed on 9/15/2005. As a consequence of this upgrade, the tip curve frequency increased. The tip cycle time decreased from ~60s to ~50s. |
| Measurements: | nsamwrlosC1.b1:
nsamwrtipC1.a1:
|