DQR ID | Subject | Data Streams Affected |
---|---|---|
D030317.1 | TWP/SMET/C1 - Reprocess: Lower Wind Speed incorrect | twpsmet60sC1.a1, twpsmet60sC1.b1 |
D040220.1 | TWP/MWR/C1 - wrong azimuth | twpmwrlosC1.b1 |
D040428.1 | TWP/SMET/C1 - Poor Performing Sensor | twpsmet60sC1.b1 |
D040824.3 | TWP/SMET/C1 - Incorrect rainrate equation used | twpsmet60sC1.b1 |
D050421.6 | TWP/SMET/C1 - Negative rainfall rates | twpsmet60sC1.b1 |
D050725.9 | TWP/MWR/C1 - Reprocessed: Revised Retrieval Coefficients | twp5mwravgC1.c1, twpmwrlosC1.b1, twpmwrtipC1.a1 |
D050928.1 | TWP/MWR/C1 - New software version (4.15) installed | twpmwrlosC1.b1, twpmwrtipC1.a1 |
D051119.1 | TWP/SKYRAD/C1 - IRT failure | twpskyrad60sC1.b1 |
D060630.34 | TWP/GNDRAD/C1 - Reprocess: Longwave Calibration error | twpgndrad60sC1.b1 |
D060817.3 | TWP/SMET/C1 - Reprocess: Barometric pressure units change | twpsmet60sC1.b1 |
D061011.2 | TWP/SMET/C1 - Reprocess: Tipping bucket rain gauge added | twpsmet60sC1.b1 |
Start Date | Start Time | End Date | End Time |
---|---|---|---|
02/27/2003 | 1750 | 03/03/2003 | 1900 |
Subject: | TWP/SMET/C1 - Reprocess: Lower Wind Speed incorrect |
DataStreams: | twpsmet60sC1.a1, twpsmet60sC1.b1 |
Description: | The lower wind speed sensor (sensor #2) was reporting values 10 times above the actual value. During an update to the logger configuration file the calibration multiplier was incorrectly entered. The multiplier inserted was .97630 when it should have been .09763. This caused the readings from this sensor to be incorrect. |
Measurements: | twpsmet60sC1.b1:
twpsmet60sC1.a1:
|
Start Date | Start Time | End Date | End Time |
---|---|---|---|
10/11/1996 | 0000 | 02/18/2004 | 2250 |
Subject: | TWP/MWR/C1 - wrong azimuth |
DataStreams: | twpmwrlosC1.b1 |
Description: | The MWR was initially installed at an azimuth angle defined as 180 degrees but the value in the configuration file was not changed from the default of 0 degrees. In examining photos taken during the installation of the AWS tower, I noticed that the MWR was rotated opposite the normal orientation. The value in the configuration file was changed to reflect the actual azimuth of the instrument. |
Measurements: | twpmwrlosC1.b1:
|
Start Date | Start Time | End Date | End Time |
---|---|---|---|
04/23/2004 | 0000 | 01/19/2005 | 1530 |
Subject: | TWP/SMET/C1 - Poor Performing Sensor |
DataStreams: | twpsmet60sC1.b1 |
Description: | On 4/23/2004 condensation was found inside the target area of the ORG lens. A spare was sent and installed but did not solve the problem of high background voltage values causing rainrate values to be recorded during no rainfall. Values range anywhere from 0.06 to 0.12 mm/hr. A new Optical Rain Gage was installed on 01/19/2005 @ 13:30 GMT alleviating the high background voltage values that lead to consistent rainfall rates of around 0.11 to 0.15 mm/hr on a consistent basis. The formula used to calculate rainfall rates from the new Optical Rain Gage is: RR (mm/hr) = 25(V^1.87) - 0.15. Older model formula = 20(V^2) - 0.05 The two formulas result in comparable data. |
Measurements: | twpsmet60sC1.b1:
|
Start Date | Start Time | End Date | End Time |
---|---|---|---|
08/03/2004 | 0307 | 08/17/2004 | 2138 |
Subject: | TWP/SMET/C1 - Incorrect rainrate equation used |
DataStreams: | twpsmet60sC1.b1 |
Description: | There are two different Optical Raingages in use at the TWP sites. The incorrect equation was used at this site. The incorrect equation is (25*(V^1.87)) - 0.15. The correct equation is (20*(V^2)) - 0.05. The correct equation was installed. |
Measurements: | twpsmet60sC1.b1:
|
Start Date | Start Time | End Date | End Time |
---|---|---|---|
10/09/1996 | 0000 | 03/09/2004 | 2243 |
Subject: | TWP/SMET/C1 - Negative rainfall rates |
DataStreams: | twpsmet60sC1.b1 |
Description: | Due to limitations of the Zeno dataloggers all voltage measurements from the optical rain gauge (ORG) were converted to rainfall rates. This resulted in negative values for rain rates. Any value below 0.10 mm/hr should be considered to be 0 mm/hr. New dataloggers alleviated this problem. New loggers were installed 03/09/2004 @ 2243 GMT. |
Measurements: | twpsmet60sC1.b1:
|
Start Date | Start Time | End Date | End Time |
---|---|---|---|
05/04/2002 | 0200 | 06/30/2005 | 2100 |
Subject: | TWP/MWR/C1 - Reprocessed: Revised Retrieval Coefficients |
DataStreams: | twp5mwravgC1.c1, twpmwrlosC1.b1, twpmwrtipC1.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). The Rosenkranz-based retrieval coefficients became active at TWP.C1 20020504.0200. The MONORTM-based retrieval coefficients became active at TWP.C1 20050630.2100. Note: The TWP.C1 data for 19961011-20050630 have been reprocessed to apply the |
Measurements: | twpmwrlosC1.b1:
twp5mwravgC1.c1:
twpmwrtipC1.a1:
|
Start Date | Start Time | End Date | End Time |
---|---|---|---|
10/31/2002 | 2200 | 09/13/2005 | 1854 |
Subject: | TWP/MWR/C1 - New software version (4.15) installed |
DataStreams: | twpmwrlosC1.b1, twpmwrtipC1.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 9/13/2005. As a consequence of this upgrade, the tip curve frequency increased. The tip cycle time decreased from ~60s to ~50s. |
Measurements: | twpmwrlosC1.b1:
twpmwrtipC1.a1:
|
Start Date | Start Time | End Date | End Time |
---|---|---|---|
11/13/2005 | 0100 | 01/10/2006 | 0145 |
Subject: | TWP/SKYRAD/C1 - IRT failure |
DataStreams: | twpskyrad60sC1.b1 |
Description: | A moisture related fault was found in the IRT cable after a day of very heavy rain. The cable was replaced but the internal power supply was apparently damaged. The instrument was replaced with a spare IRT. |
Measurements: | twpskyrad60sC1.b1:
|
Start Date | Start Time | End Date | End Time |
---|---|---|---|
08/02/2004 | 0700 | 12/21/2005 | 2204 |
Subject: | TWP/GNDRAD/C1 - Reprocess: Longwave Calibration error |
DataStreams: | twpgndrad60sC1.b1 |
Description: | Modified pyrgeometer calibration procedures were implemented beginning in December 2003. These modified procedures introduced a calibration bias in the longwave data. The previous procedures were re-implemented at all sites between December 2005 and February 2006 to restore proper calibrations. The data collected while the incorrect procedures were in place are being reprocessing to remove the calibration bias. Note, this also affected standard deviation, maximum and minimum data fields. |
Measurements: | twpgndrad60sC1.b1:
|
Start Date | Start Time | End Date | End Time |
---|---|---|---|
10/09/1996 | 0000 | 08/02/2004 | 1911 |
Subject: | TWP/SMET/C1 - Reprocess: Barometric pressure units change |
DataStreams: | twpsmet60sC1.b1 |
Description: | Barometric pressure data during this time period is reported in hPa. After this time, the data have been converted to kPa to standardize the measurement units among ARM sites and to conform to accepted standard units determined by the scientific community. |
Measurements: | twpsmet60sC1.b1:
|
Start Date | Start Time | End Date | End Time |
---|---|---|---|
10/09/1996 | 0000 | 10/17/2006 | 0000 |
Subject: | TWP/SMET/C1 - Reprocess: Tipping bucket rain gauge added |
DataStreams: | twpsmet60sC1.b1 |
Description: | A tipping bucket rain gauge was added to the TWP.C1 SMET suite of instruments on 20061017. Effective 20060926, two new variables (count and rain amount) were added to the end of the twpsmet60sC1.b1 datastream. Between 9/26 and 10/17, the data for these two variables are filled with zeros. Users should not use the data during this period as the zeros are not representative of the rain fall at the site. When reprocessing of this datastream occurs these variables will be added for the 19961009-20060926 and data from 19961009-20061017 will be filled with -9999 (missing). |
Measurements: | twpsmet60sC1.b1:
|