NSA/MWRP/C1 - Incorrect surface measurements

The MWRP surface temperature and pressure readings were in disagreement with those from 
other instruments. The possible cause of the disagreement was ice buildup around the 
sensors.  Readings returned to normal March 29.

The temperature readings were more affected. Since the readings are erratic, with large 
oscillations, it is not possible to correct them. Disregard the surface temperature and 
humidity readings during this time. The wrong readings will affect the first layer of the 
temperature and humidity profiles as well.

• Ambient surface pressure(surfacePressure)
• Surface water vapor density at instrument(surfaceWaterVaporDensity)
• Ambient surface absolute temperature(surfaceTemperature)
• Ambient surface relative humidity(surfaceRelativeHumidity)

NSA/MWRP/C1 - Reprocessed: 6-channel retrieval replaced by 5-channel retrieval

Due to repeated failure of the V-band receiver and calibration problems, the 6-channel 
retrieval was retired and a new 5-channel retrieval which uses only the K-band channels was 
implemented.

All data previously processed with the 6-channel retrieval have been reprocessed.

Please note that the 7 channels (brightness temperatures) in the V-band range (51 to 60 
GHz) should not be used.  See D080331.1 and D080331.2.

• Retrieved liquid water path(liquidWaterPath)
• Retrieved liquid water path using only 23.835 and 30.0 GHz(liquidWaterPath2)
• Microwave brightness temperature(brightnessTemperature)

NSA/MWRP/C1 - V-band Noise diode unstable

Sometimes between Jan and March 2007 the V-band noise diode started to be unstable. V-band 
channels during this period show large discrepancies with model computations. The 
problem was evident during the month of January. During February and March the problem was less 
visible, however measurement model comparisons show an increased bias. The instrument 
was calibrated with LN2 on March 15 and the calibration results showed a large drift in the 
calibration parameters.  The hardware failure will have consequences in the retrievals 
of temperature and relative humidity profiles. 

It is difficult to establish when the failure started. Disregard the V-band channels 
during this period. Vertical profiles of temperature and humidity are affected as well. Please 
note that this DQR only covers the 7 channels (brightness temperatures) in the V-band 
range (51 to 60 GHz). The 5 K-band channels (20-31 GHz) are not affected.

• Derived relative humidity(relativeHumidity)
• Retrieved water vapor density(waterVaporDensity)
• Interpolated dewpoint temperature(dewpointTemperature)
• Microwave brightness temperature(brightnessTemperature)
• Derived virtual temperature(virtualTemperature)
• Interpolated water vapor mixing ratio(waterVaporMixingRatio)