DQR ID | Subject | Data Streams Affected |
---|---|---|
D060419.3 | NIM/MWRP/M1 - Instrument noise problem | nimmwrpM1.00, nimmwrpM1.b1, nimmwrprawM1.00 |
D060619.1 | NIM/MWRP/M1 - Reprocessed - New retrieval coefficients | nimmwrpM1.b1 |
D060713.1 | NIM/MWRP/M1 - 51.25 GHz channel calibration drifted | nimmwrpM1.b1 |
D060929.1 | NIM/MWRP/M1 - Sun in radiometer's field of view | nimmwrpM1.b1 |
D080304.3 | NIM/MET/M1 - ORG Data Underestimated Precipitation | nimmetM1.b1 |
D080428.7 | NIM/MET/M1 - Reprocess: ORG Data has very small rainrate values | nimmetM1.b1 |
D081022.11 | NIM/MET/M1 - Wind Speed data contain offset due to induced voltage | nimmetM1.b1 |
Start Date | Start Time | End Date | End Time |
---|---|---|---|
01/01/2006 | 0000 | 01/08/2007 | 0000 |
Subject: | NIM/MWRP/M1 - Instrument noise problem |
DataStreams: | nimmwrpM1.00, nimmwrpM1.b1, nimmwrprawM1.00 |
Description: | There are spikes and elevated noise in MWRP data. The origine of the spikes is RF interference from various sources. All brightness temperatures are affected, but in particular the 5 K-band channels. LWP retrievals are noisy and affected by spikes as a result. |
Measurements: | nimmwrpM1.00:
nimmwrpM1.b1:
nimmwrprawM1.00:
|
Start Date | Start Time | End Date | End Time |
---|---|---|---|
01/01/2006 | 0000 | 08/24/2006 | 2300 |
Subject: | NIM/MWRP/M1 - Reprocessed - New retrieval coefficients |
DataStreams: | nimmwrpM1.b1 |
Description: | Occasionally, the retrieved relative humidity was exceeding 120%. Upon reviewing the data it was noticed that the high values were appearing in the highest layers (above 8 km) and especially during spring season. Since retrievals at the highest levels are mainly affected by the climatology used to constrain the retrievals, we reviewed the statistical coefficients that were used to retrieve temperature and humidity. It was discovered that, in the training dataset (radiosonde), there were a few outliers (invalid radiosonde soundings) that had escaped the screening process and were affecting the computations of the retrieval coefficients. We recomputed the retrieval coefficients with the newly screened set of radiosonde data and reprocessed all the previous data at Niamey. The reprocessed data were archived in August 2006. The new coefficients improve temperature and humidity profiles in two ways. The relative humidity will not exceed 120% in the upper layers and the temperature profiles will be in better agreement with the sonde in the first 4 km. |
Measurements: | nimmwrpM1.b1:
|
Start Date | Start Time | End Date | End Time |
---|---|---|---|
05/05/2006 | 0000 | 01/08/2007 | 0000 |
Subject: | NIM/MWRP/M1 - 51.25 GHz channel calibration drifted |
DataStreams: | nimmwrpM1.b1 |
Description: | After a power outage on May 5 the 51.25 GHz had a slight change in the calibration. The resulting LWP computed by using all 6 channels increased of about 0.025 mm (25 g/m2). |
Measurements: | nimmwrpM1.b1:
|
Start Date | Start Time | End Date | End Time |
---|---|---|---|
08/01/2006 | 0000 | 08/31/2006 | 2359 |
Subject: | NIM/MWRP/M1 - Sun in radiometer's field of view |
DataStreams: | nimmwrpM1.b1 |
Description: | Around noon local time every day there is a spike in the brightness temperature data. This is due to the sun being in the field of view of the radiometer. PWV and LWP are affected as a consequence |
Measurements: | nimmwrpM1.b1:
|
Start Date | Start Time | End Date | End Time |
---|---|---|---|
01/06/2006 | 0000 | 01/06/2007 | 2359 |
Subject: | NIM/MET/M1 - ORG Data Underestimated Precipitation |
DataStreams: | nimmetM1.b1 |
Description: | The ORG underestimated precipitation by about 38% during the entire NIM deployment. No troubleshooting technique or replacement of gage was successful in correcting the problem. |
Measurements: | nimmetM1.b1:
|
Start Date | Start Time | End Date | End Time |
---|---|---|---|
01/06/2006 | 0000 | 01/07/2007 | 2359 |
Subject: | NIM/MET/M1 - Reprocess: ORG Data has very small rainrate values |
DataStreams: | nimmetM1.b1 |
Description: | The ORG data is collected via analog signal and not digital. Therefore, we continuously collect data even when no rain is occurring. We also capture small events such as leaves, large bugs, dust, etc blowing through the measurement path. Because this discrete event occurs quickly the value is usually captured for 1 or 2 seconds. This value is then averaged to the minute producing rainrate on the order of .009 mm/hr or less. These values are not indicative of rain and should be removed from the record or summing over long periods can bias the climate record. We are reprocessing the data to remove these small values and are adjusting the collection program to remove them before ingest. |
Measurements: | nimmetM1.b1:
|
Start Date | Start Time | End Date | End Time |
---|---|---|---|
01/06/2006 | 0000 | 01/07/2007 | 2359 |
Subject: | NIM/MET/M1 - Wind Speed data contain offset due to induced voltage |
DataStreams: | nimmetM1.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: | nimmetM1.b1:
|