DQR ID | Subject | Data Streams Affected |
---|---|---|
D050210.1 | TWP/SMET/C3 - Data non-representative | twpsmet60sC3.b1 |
D050418.2 | TWP/SMET/C3 - Lower wind direction sensor failure | twpsmet60sC3.b1 |
D050725.11 | TWP/MWR/C3 - Reprocess - Revised Retrieval Coefficients | twpmwrlosC3.a1, twpmwrlosC3.b1, twpmwrtipC3.a1 |
D050928.5 | TWP/MWR/C3 - New software version (4.15) installed | twpmwrlosC3.b1, twpmwrtipC3.a1 |
D051214.1 | TWP/MWR/C3 - REPROCESS- Updated retrieval coefficients | twpmwrlosC3.b1, twpmwrtipC3.a1 |
D061011.4 | TWP/SMET/C3 - Reprocess: Tipping bucket rain gauge added | twpsmet60sC3.b1 |
D081022.8 | TWP/SMET/C3 - Wind Speed data contain offset due to induced voltage | twpsmet60sC3.b1 |
D090225.3 | TWP/SMET/C3 - Reprocess: Temperature data biased low | twpsmet60sC3.b1 |
D090515.1 | TWP/SMET/C3 - Reprocess: Temperature Biased low by 1.06 Degrees | twpsmet60sC3.b1 |
Start Date | Start Time | End Date | End Time |
---|---|---|---|
02/09/2005 | 2310 | 02/09/2005 | 2320 |
Subject: | TWP/SMET/C3 - Data non-representative |
DataStreams: | twpsmet60sC3.b1 |
Description: | Tower mast was lowered for inspection. Data during this time is non-representative. |
Measurements: | twpsmet60sC3.b1:
|
Start Date | Start Time | End Date | End Time |
---|---|---|---|
04/14/2005 | 0230 | 04/19/2005 | 0050 |
Subject: | TWP/SMET/C3 - Lower wind direction sensor failure |
DataStreams: | twpsmet60sC3.b1 |
Description: | The lower wind direction sensor failed on 4/14 and disagrees significantly with the upper wind direction sensor. The lower wind sensor reports a constant value around 0-15 degrees since it failed. Testing showed that excitation channel two on the logger was the problem. Logger was replaced by spare. |
Measurements: | twpsmet60sC3.b1:
|
Start Date | Start Time | End Date | End Time |
---|---|---|---|
02/27/2002 | 0151 | 06/30/2005 | 2100 |
Subject: | TWP/MWR/C3 - Reprocess - Revised Retrieval Coefficients |
DataStreams: | twpmwrlosC3.a1, twpmwrlosC3.b1, twpmwrtipC3.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 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 was active at TWP.C3 from inception of the data, 20020227.0151. The MONORTM-based retrieval coefficients became active at TWP.C3 20050630.2100. 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: | twpmwrlosC3.a1:
twpmwrlosC3.b1:
twpmwrtipC3.a1:
|
Start Date | Start Time | End Date | End Time |
---|---|---|---|
10/03/2002 | 0000 | 09/20/2005 | 2156 |
Subject: | TWP/MWR/C3 - New software version (4.15) installed |
DataStreams: | twpmwrlosC3.b1, twpmwrtipC3.a1 |
Description: | A problem began with the installation of MWR.EXE version 4.12 in October 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 9/20/2005. As a consequence of this upgrade, the tip curve frequency increased. The tip cycle time decreased from ~60s to ~50s. |
Measurements: | twpmwrlosC3.b1:
twpmwrtipC3.a1:
|
Start Date | Start Time | End Date | End Time |
---|---|---|---|
02/27/2002 | 0000 | 12/12/2005 | 1600 |
Subject: | TWP/MWR/C3 - REPROCESS- Updated retrieval coefficients |
DataStreams: | twpmwrlosC3.b1, twpmwrtipC3.a1 |
Description: | The statistical retrieval coefficients currently in use at the Darwin (TWP/C3) site were developed using radiosonde RS80 launched from Manus Island during the TOGA-COARE experiment. Data from Manus Island have minimal seasonality, therefore a single, annual set of coefficients was used at all three sites. Retrievals using these coefficients are sufficiently accurate especially during the local summer months (December-January). However, the Darwin site displays a summer/winter seasonality resulting in larger differences during the southern winter (May- June). Since we now have enough radiosonde soundings (RS80 and RS90) available at the Darwin site, the Darwin coefficients were modified to better reflect the local seasonality. |
Measurements: | twpmwrlosC3.b1:
twpmwrtipC3.a1:
|
Start Date | Start Time | End Date | End Time |
---|---|---|---|
03/12/2002 | 0000 | 09/26/2006 | 1435 |
Subject: | TWP/SMET/C3 - Reprocess: Tipping bucket rain gauge added |
DataStreams: | twpsmet60sC3.b1 |
Description: | A tipping bucket rain gauge was added to the SMET suite of instruments effective 20060926. Two new variables (count and rain amount) were added at the end of the twpsmet60sC1.b1 datastream. When reprocessing of this datastream occurs these variables will be added with -9999 (missing) as the value for dates prior to gauge installation. |
Measurements: | twpsmet60sC3.b1:
|
Start Date | Start Time | End Date | End Time |
---|---|---|---|
03/12/2002 | 0000 | 10/17/2008 | 0627 |
Subject: | TWP/SMET/C3 - Wind Speed data contain offset due to induced voltage |
DataStreams: | twpsmet60sC3.b1 |
Description: | The marine model of the RM Young wind sensor needs twisted pair shielded cable. The manufacturer did not originally supply the pigtail with twisted pair shielded cable. Use of twisted pair shielded cable for the rest of the cable run to the logger was also not specified. This caused an induced voltage in the wind speed line from the wind direction excitation. The induced voltage varied from sensor to sensor and probably changed anytime the cable was replaced or parts of the wind sensor were repaired or replaced. The induced voltage has been seen to vary from 0.15 m/s to as much as 1.08 m/s. |
Measurements: | twpsmet60sC3.b1:
|
Start Date | Start Time | End Date | End Time |
---|---|---|---|
05/19/2004 | 0519 | 04/19/2005 | 0419 |
Subject: | TWP/SMET/C3 - Reprocess: Temperature data biased low |
DataStreams: | twpsmet60sC3.b1 |
Description: | Due to a datalogger problem, the temperature data were biased low by 2.13 degrees C. The data will be reprocessed. |
Measurements: | twpsmet60sC3.b1:
|
Start Date | Start Time | End Date | End Time |
---|---|---|---|
04/19/2005 | 0420 | 04/04/2009 | 0115 |
Subject: | TWP/SMET/C3 - Reprocess: Temperature Biased low by 1.06 Degrees |
DataStreams: | twpsmet60sC3.b1 |
Description: | The temperature of the SMET system was biased low by 1.06 Deg C due to a non-precision resistor being used int he measurement circuit. The data will be reprocessed. Saturation Vapor pressure and Vapor pressure will have to be reprocessed also. Add 1.06 degrees to the temperature data. Correct Sat Vap Press using the Buck approximation: Es = 6.1121exp((17.502*T)/(240.97 + T) where T is the temperature in C. Correct Vapor pressure using: E = (RH*Es)/100 |
Measurements: | twpsmet60sC3.b1:
|