NSA/MWRP/C1 - Missing data

Data are missing and unrecoverable.

• Level of free convection pressure(levelFreeConvectionPres)
• Derived virtual temperature(virtualTemperature)
• Lifting condensation level pressure(liftingCondensationLevelPres)
• Equilibrium level pressure(equilibriumLevelPres)
• Data quality flags(dataQualityFlags)
• Expected root-mean-square error in precipitable water retrieval using only
  23.835 and 30.0 GHz(totalPrecipitableWater2RmsError)
• Surface water vapor density at instrument(surfaceWaterVaporDensity)
• Derived relative humidity(relativeHumidity)
• Flag indicating moisture sensor status(wetWindowFlag)
• Retrieved cloud liquid water content(liquidWaterContent)
• Retrieved liquid water path using only 23.835 and 30.0 GHz(liquidWaterPath2)
• Equilibrium level(equilibriumLevel)
• Zenith-pointing infrared temperature at 10um(infraredTemperature)
• Convective Available Potential Energy(cape)
• time(time)
• Time offset of tweaks from base_time(time_offset)
• Expected root-mean-square error in liquid water path retrieval(liquidWaterPathRmsError)
• Expected root-mean-square error in water vapor density retrieval(waterVaporDensityRmsError)
• atmospheric pressure at mean sea level and at tropopause (NGM250 predicted)(pressure)
• Internal blackbody reference temperature(blackbodyTemperature)
• Microwave brightness temperature(brightnessTemperature)
• Retrieved liquid water path(liquidWaterPath)
• Interpolated water vapor mixing ratio(waterVaporMixingRatio)
• Dummy altitude for Zeb(alt)
• Ambient surface pressure(surfacePressure)
• Lifting condensation level(liftingCondensationLevel)
• Array of heights for the range gates(height)
• Level of free convection(levelFreeConvection)
• elevation(elevation)
• Expected root-mean-square error in liquid water content retrieval(liquidWaterContentRmsError)
• Expected root-mean-square error in liquid water path retrieval using only 23.835
  and 30.0 GHz(liquidWaterPath2RmsError)
• Ambient surface relative humidity(surfaceRelativeHumidity)
• Interpolated dewpoint temperature(dewpointTemperature)
• Ambient surface absolute temperature(surfaceTemperature)
• Total precipitable water vapor, from microwave radiometer(totalPrecipitableWater)
• Expected root-mean-square error in temperature retrieval(temperatureRmsError)
• Frequency(frequency)
• air temperature (NGM250 predicted)(temperature)
• base time(base_time)
• Retrieved water vapor density(waterVaporDensity)
• Expected root-mean-square error in precipitable water retrieval(totalPrecipitableWaterRmsError)
• lon(lon)
• Cloud base height(cloudBaseHeight)
• lat(lat)
• Retrieved total precipitable water vapor using only 23.835 and 30.0 GHz(totalPrecipitableWater2)
• azimuth(azimuth)

NSA/MWRP/C1 - Incorrect calibration

On 4/12 a calibration was attempted but the calibration was not successful. A new 
calibration was completed on 4/13 20:00 UTC.  Data between the two calibration attempts are 
incorrect and should be disregarded.

• Level of free convection pressure(levelFreeConvectionPres)
• Derived virtual temperature(virtualTemperature)
• Lifting condensation level pressure(liftingCondensationLevelPres)
• Equilibrium level pressure(equilibriumLevelPres)
• Data quality flags(dataQualityFlags)
• Expected root-mean-square error in precipitable water retrieval using only
  23.835 and 30.0 GHz(totalPrecipitableWater2RmsError)
• Surface water vapor density at instrument(surfaceWaterVaporDensity)
• Derived relative humidity(relativeHumidity)
• Flag indicating moisture sensor status(wetWindowFlag)
• Retrieved cloud liquid water content(liquidWaterContent)
• Retrieved liquid water path using only 23.835 and 30.0 GHz(liquidWaterPath2)
• Equilibrium level(equilibriumLevel)
• Zenith-pointing infrared temperature at 10um(infraredTemperature)
• Convective Available Potential Energy(cape)
• time(time)
• Time offset of tweaks from base_time(time_offset)
• Expected root-mean-square error in liquid water path retrieval(liquidWaterPathRmsError)
• Expected root-mean-square error in water vapor density retrieval(waterVaporDensityRmsError)
• atmospheric pressure at mean sea level and at tropopause (NGM250 predicted)(pressure)
• Internal blackbody reference temperature(blackbodyTemperature)
• Microwave brightness temperature(brightnessTemperature)
• Retrieved liquid water path(liquidWaterPath)
• Interpolated water vapor mixing ratio(waterVaporMixingRatio)
• Dummy altitude for Zeb(alt)
• Ambient surface pressure(surfacePressure)
• Lifting condensation level(liftingCondensationLevel)
• Array of heights for the range gates(height)
• Level of free convection(levelFreeConvection)
• elevation(elevation)
• Expected root-mean-square error in liquid water content retrieval(liquidWaterContentRmsError)
• Expected root-mean-square error in liquid water path retrieval using only 23.835
  and 30.0 GHz(liquidWaterPath2RmsError)
• Ambient surface relative humidity(surfaceRelativeHumidity)
• Interpolated dewpoint temperature(dewpointTemperature)
• Ambient surface absolute temperature(surfaceTemperature)
• Total precipitable water vapor, from microwave radiometer(totalPrecipitableWater)
• Expected root-mean-square error in temperature retrieval(temperatureRmsError)
• Frequency(frequency)
• air temperature (NGM250 predicted)(temperature)
• base time(base_time)
• Retrieved water vapor density(waterVaporDensity)
• Expected root-mean-square error in precipitable water retrieval(totalPrecipitableWaterRmsError)
• lon(lon)
• Cloud base height(cloudBaseHeight)
• lat(lat)
• Retrieved total precipitable water vapor using only 23.835 and 30.0 GHz(totalPrecipitableWater2)
• azimuth(azimuth)

NSA/MWRP/C1 - Bad calibration values

After calibration was completed on 4/26/2006 the last value in the V-band calibration file 
was corrupted. V-band data are wrong between 4/26 19:30 and 4/27 15:27 when the 
corrupted values were removed.

• Raw data stream - documentation not supported(raw)

• Expected root-mean-square error in water vapor density retrieval(waterVaporDensityRmsError)
• Derived virtual temperature(virtualTemperature)
• air temperature (NGM250 predicted)(temperature)
• Retrieved water vapor density(waterVaporDensity)
• Derived relative humidity(relativeHumidity)
• Retrieved cloud liquid water content(liquidWaterContent)
• Cloud base height(cloudBaseHeight)
• Microwave brightness temperature(brightnessTemperature)
• Interpolated water vapor mixing ratio(waterVaporMixingRatio)
• Interpolated dewpoint temperature(dewpointTemperature)

• Raw data stream - documentation not supported(raw)

NSA/MWR/C1 - TKAIR sensor failure

Between 7/14 and 7/28 the tkair variable is missing most of the time and sometimes has 
large negative spikes.  On 7/28, the sensor was cleaned of corrosion and the readings came 
back to normal.

• Ambient temperature(tkair)

NSA/SONDE/C1 - Noisy/Unstable RH and dew point data

The RH readings during the first 8 minutes of this sounding include three apparently 
incorrect oscillations to near-zero values.  After checking the absolutely raw data, it seems 
as though this period was excessively noisy, resulting in many missing values.  The noise 
abatted and the remaining sounding values are valid.

• Surface dew point temperature(dp)
• Relative humidity inside the instrument enclosure(rh)

NSA/SONDE/C1 - Bad surface RH and temperature values

This is a subtle problem that might escape notice.  For the identified sonde launches, the 
ground station lost its signal between the time it was removed from the ground check set 
and the time it was launched.  As a result, the software, which automatically determines 
the launch time and surface conditions at time of launch mistakenly used values of 
temperature and RH representative of the ground check set and the GW rather than of the 
ambient conditions before launch.  The bad values influenced only the first few samples and the 
remainder of the sounding values are correct.  

A procedural problem was identified and corrected.

• Dry bulb temperature(tdry)
• Surface dew point temperature(dp)
• Relative humidity inside the instrument enclosure(rh)

NSA/SONDE/C1 - RH values offset due to error in ground check

Background: After installation of the latest software update , we began performing formal 
ground checks on RS92 radiosondes.  By comparing the radiosonde readings with reference 
values in a controlled environment, the ground check is intended to ensure that the 
radiosonde sensors are in calibration before launch.  The radisonde values during the ground 
check process are recorded automatically; the reference values are entered by the operator. 
 If the radiosonde readings vary from the reference values, the system 'corrects' the 
radiosonde values.  In the case of RH, the correction is applied as an offset (true RH = 
indicated RH + correction).

Problem: Some operators misunderstood the ground-check procedure and entered the 
radiosonde values of RH rather than the reference value (assumed 0%RH), thus, some soundings done 
during this period have RH values that are different from what they would be if the 
ground check procedure had been done correctly.

Consequence:  Because the RH corrections generally are small (averaging about 0.5% RH) and 
the precision of the reported RH data during this time period is 1% RH, some values will 
not be affected at all; others will be off by about 1% RH (still within the stated 
accuracy of the sensor).  Furthermore, because entering the radiosonde value as the reference 
value results in a near zero 'correction,' one may view these soundings as being done 
without the ground check correction.  Also note that the dew point value will be suspect as well.

I am attaching below a listing of the soundings that were affected during the indicated 
time period.  Users can see the magnitude of the problem and choose whether or not to apply 
an offset in RH.  Note that application of the offset to the processed RH data (in the 
netCDF file) will not have the same effect of applying the correction to the absolutely 
raw data (before processing), but the differences should be insignificant.  Also note that 
the corrections for each sounding are included in the netCDF header information.  These 
attributes are named 'humidity_correction' and 'humidity_correction_2'.  The values of RH 
indicated by the radiosonde while it is in the ground check set are in attributes 
'humidity_gc_sonde' and 'humidity_gc_sonde_2.'  There is an RH reading for each of the two RH 
sensors used in the RS92 radiosonde.

Here is the list - RH1 and RH2 are the radiosonde readings in the ground check set.  Ref 
is the reference value entered by the operator.  The correcte reference value should be 
0%.  To obtain an approximation to the RH value that would have been recorded if the ground 
check had been done properly, subtract the Ref value from the indicated RH.

 YYYYMMDD  HHMM  SerialNo     RH1     RH2     Ref
 20060713  0532  B1924431    0.30    0.20    0.30
 20060713  1751  B1854963    0.20    0.30    0.30
 20060714  0521  B1924425    0.40    0.40    0.40
 20060714  1739  B1854206    0.30    0.30    0.30
 20060715  0522  B1715127    1.20    1.20    1.20
 20060715  1737  B1854966    0.60    0.60    0.60
 20060716  0508  B1715126    0.40    0.40    0.40
 20060716  1732  B1844098    0.50    0.50    0.50
 20060717  0517  B1914170    0.40    0.40    0.40
 20060718  0516  B1914173    0.70    0.70    0.70
 20060720  0523  B1854149    0.40    0.40    0.40
 20060721  0517  B1914153    0.40    0.40    0.40
 20060722  0521  B1844097    1.00    1.10    1.10
 20060722  1730  B1914174    0.60    0.70    0.70
 20060723  0537  B1714439    0.40    0.40    0.40
 20060723  1734  B1734155    0.50    0.50    0.50
 20060724  0529  B1134336    0.50    0.50    0.50
 20060725  0525  B1754099    0.60    0.70    0.70
 20060726  0541  B1844108    1.80    1.80    1.80
 20060727  0520  B1714382    0.70    0.80    0.70
 20060728  0531  B1854116    0.80    0.80    0.80
 20060729  0527  B1724027    1.00    1.00    1.00
 20060729  1726  B1714392    0.70    0.80    0.80
 20060730  0522  B1854100    0.70    0.80    0.80
 20060730  1724  B1854764    0.90    1.00    1.00
 20060731  0515  B1664086    0.90    0.80    0.90
 20060801  0520  B1724758    1.50    1.50    1.50
 20060801  1729  B1754116    1.10    1.10    1.10
 20060802  0518  B1724516    0.80    0.80    0.80
 20060803  0523  B1674148    0.80    0.80    0.80
 20060804  0532  B1754092    0.90    0.90    0.90
 20060804  1727  B1844117    3.50    3.50    3.50
 20060805  0531  B1714741    0.30    0.30    0.30
 20060805  1728  B1754098    0.30    0.30    0.30
 20060806  0528  B1844115    0.40    0.40    0.40
 20060806  1728  B1914161    0.20    0.20    0.20
 20060807  0530  B1714549    0.30    0.30    0.30
 20060808  0517  B1844107    0.50    0.50    0.50
 20060808  1744  B1914166    0.20    0.20    0.20
 20060809  0527  B1914164    0.30    0.40    0.40
 20060809  1736  B1914163    0.30    0.30    0.30
 20060810  0521  B1914160    0.40    0.50    0.50
 20060810  1745  B1744671    0.40    0.40    0.40
 20060811  0525  B1854965    0.50    0.50    0.50
 20060811  1753  B1724131    0.10    0.10    0.10
 20060812  0527  B1754104    0.50    0.50    0.50
 20060812  1740  B1854256    0.30    0.40    0.40
 20060813  0522  B1854240    0.30    0.40    0.40
 20060814  0525  B1714106    0.20    0.20    0.20
 20060814  1742  B1854106    0.40    0.40    0.40
 20060815  0534  B1914169    0.50    0.60    0.60
 20060815  1734  B1854233    0.60    0.70    0.70
 20060816  0539  B1724791    0.20    0.20    0.20
 20060816  1732  B1914171    0.10    0.20    0.20
 20060817  0535  B1354283    0.10    0.10    0.10
 20060817  1740  B1354574    0.40    0.40    0.40
 20060818  0516  B1354633    0.50    0.40    0.50
 20060818  1744  B1364673    0.20    0.20    0.20
 20060819  0538  B1364126    0.20    0.30    0.30
 20060819  1745  B1354598    0.50    0.60    0.60
 20060820  0532  B1354290    1.10    1.10    1.10
 20060820  1729  B1354317    0.40    0.40    0.40
 20060821  0530  B1354545    0.60    0.70    0.70
 20060821  1728  B1354516    0.70    0.70    0.70
 20060822  0524  B1354619    0.50    0.60    0.60
 20060822  1728  B1364377    0.40    0.40    0.40
 20060823  0533  B1354309    0.30    0.30    0.30
 20060823  1730  B1354527    0.70    0.70    0.70
 20060824  0533  B1354230    0.60    0.60    0.60
 20060824  1812  B1354587    0.70    0.70    0.70
 20060825  0517  B1354614    0.70    0.70    0.70
 20060825  1730  B1354630    0.60    0.60    0.60
 20060826  0537  B1334114    0.90    0.90    0.90
 20060826  1734  B1354246    0.70    0.70    0.70
 20060827  0508  B1354534    0.70    0.70    0.70
 20060827  1729  B1354618    0.60    0.60    0.60
 20060828  0517  B1354115    0.40    0.40    0.40
 20060828  1738  B1354206    0.50    0.60    0.60
 20060829  0516  B1354617    0.50    0.60    0.60
 20060829  1717  B1354622    0.50    0.60    0.60
 20060830  0511  B1354314    0.40    0.50    0.50
 20060830  1732  B1354537    0.60    0.70    0.70
 20060831  1802  B1354239    0.60    0.80    0.80
 20060905  1724  B1354626    0.60    0.60    0.60
 20060906  0522  B1354525    0.60    0.80    0.80
 20060906  1734  B1354107    0.50    0.50    0.50
 20060907  0537  B1354543    0.70    0.70    0.70
 20060907  1803  B1354586    0.80    0.80    0.80
 20060908  0531  B1354519    0.60    0.60    0.60
 20060908  1728  B1354224    0.60    0.60    0.60
 20060909  0534  B1354532    0.70    0.80    0.80
 20060909  1732  B1354513    0.80    0.90    0.90
 20060910  0516  B1354125    0.60    0.70    0.60
 20060910  1727  B1354110    0.40    0.50    0.50
 20060911  0528  B1354235    0.90    0.90    0.90
 20060911  1849  B1354514    0.70    0.70    0.70
 20060912  0525  B1354124    0.60    0.70    0.70
 20060913  0534  B1344478    0.50    0.50    0.50
 20060914  0520  B1354226    0.70    0.70    0.70
 20060915  0529  B1344459    0.40    0.50    0.50
 20060916  0532  B1344469    0.50    0.40    0.50
 20060916  1732  B1354106    0.50    0.60    0.60
 20060917  0527  B1354210    0.70    0.70    0.70
 20060918  0533  B1354087    0.60    0.60    0.60
 20060919  0526  B1354097    0.70    0.50    0.60
 20060920  0516  B1344462    0.50    0.40    0.50
 20060920  1810  B1354536    0.70    0.70    0.70
 20060921  0534  B1354112    0.50    0.60    0.60
 20060921  1800  B1344502    0.40    0.40    0.40
 20060922  0525  B1354531    0.70    0.80    0.80
 20060922  1736  B1354541    0.70    0.70    0.70
 20060923  0519  B1354101    0.50    0.60    0.60
 20060923  1738  B1354576    0.70    0.50    0.70
 20060924  0536  B1354095    0.60    0.60    0.60
 20060925  0536  B1354098    0.60    0.60    0.60
 20060925  1755  B1354100    0.50    0.50    0.50
 20060926  0531  B1334691    0.70    0.70    0.70
 20060926  1742  B1354108    0.40    0.50    0.50

• Surface dew point temperature(dp)
• Relative humidity inside the instrument enclosure(rh)

NSA/SONDE/C1 - Increased precision for alt, dp, pres, rh, tdry

The output precision of the following variables was increased 20060929:

   alt	changed from 1m to 0.1m
   dp	changed from 0.1degC to 0.01degC
   pres changed from 0.1 hPa to 0.01 hPa
   RH	changed from 1%RH to 0.01%RH
   tdry changed from .1degC to 0.01degC

Note that the increase in precision does not necessarily imply an increase
in accuracy.  Users are cautioned to continue to use their best scientific
judgement when using these or any other data.

• Dummy altitude for Zeb(alt)
• Dry bulb temperature(tdry)
• Surface dew point temperature(dp)
• Retrieved pressure profile(pres)
• Relative humidity inside the instrument enclosure(rh)

NSA/MWRP/C1 - Reprocessed: Re-calibration

After being re-installed the radiometer was calibrated with liquid nitrogen.
Data between 8/8 and 9/6 have been reprocessed to apply the revised calibrations.

• Level of free convection pressure(levelFreeConvectionPres)
• Derived virtual temperature(virtualTemperature)
• Lifting condensation level pressure(liftingCondensationLevelPres)
• Equilibrium level pressure(equilibriumLevelPres)
• Expected root-mean-square error in precipitable water retrieval using only
  23.835 and 30.0 GHz(totalPrecipitableWater2RmsError)
• Surface water vapor density at instrument(surfaceWaterVaporDensity)
• Retrieved cloud liquid water content(liquidWaterContent)
• Retrieved liquid water path using only 23.835 and 30.0 GHz(liquidWaterPath2)
• Equilibrium level(equilibriumLevel)
• Zenith-pointing infrared temperature at 10um(infraredTemperature)
• Convective Available Potential Energy(cape)
• Expected root-mean-square error in liquid water path retrieval(liquidWaterPathRmsError)
• Expected root-mean-square error in water vapor density retrieval(waterVaporDensityRmsError)
• Internal blackbody reference temperature(blackbodyTemperature)
• Retrieved liquid water path(liquidWaterPath)
• Microwave brightness temperature(brightnessTemperature)
• Interpolated water vapor mixing ratio(waterVaporMixingRatio)
• Lifting condensation level(liftingCondensationLevel)
• Level of free convection(levelFreeConvection)
• Expected root-mean-square error in liquid water content retrieval(liquidWaterContentRmsError)
• Interpolated dewpoint temperature(dewpointTemperature)
• Expected root-mean-square error in liquid water path retrieval using only 23.835
  and 30.0 GHz(liquidWaterPath2RmsError)
• Total precipitable water vapor, from microwave radiometer(totalPrecipitableWater)
• Retrieved water vapor density(waterVaporDensity)
• Expected root-mean-square error in precipitable water retrieval(totalPrecipitableWaterRmsError)
• Cloud base height(cloudBaseHeight)
• Retrieved total precipitable water vapor using only 23.835 and 30.0 GHz(totalPrecipitableWater2)

NSA/SONDE/C1 - Incorrect surface values of T and RH

The radiosonde was launched too quickly after being removed from the ground check set.  As 
a result, the system did not equilibrate with the local ground conditions and the 
automatically entered surface values are incorrect.

• Dry bulb temperature(tdry)
• Surface dew point temperature(dp)
• Relative humidity inside the instrument enclosure(rh)

NSA/MWR/C1 - Rain sensor always on

The rain sensor was always on between 10/5 and 10/23 2006.
The user should be aware that not all data flagged as rainy are actually rainy. The 
problem was caused by a shift in the sensitivity of the rain sensor and was corrected by 
changing the sensor threshold in the configuration file.

• Water on Teflon window (1=WET, 0=DRY)(wet_window)

• Water on Teflon window (1=WET, 0=DRY)(wet_window)

NSA/SONDE/C1 - RH sensor failure

It appears that one of the two RH sensors on this radiosonde was affected by ice after 
emerging from a low cold cloud.  As a result the reported RH values oscillate by about 10 
percent until the alternate heating cycle stops.  I suspect the lower value is more close 
to correct, but can't be absolutely sure.

• Surface dew point temperature(dp)
• Relative humidity inside the instrument enclosure(rh)

NSA/MWRP/C1 - Reprocessed: K-Band calibration drift

At the beginning of November, the K-band channel calibration started to drift. The MWRP 
brightness temperatures were about 1.5 K higher than the MWR-measured brightness 
temperatures. By the half of the month the differences were more than 2 K to become about 4 K by 
the end of November. On Nov 27 new calibration coefficients were derived and uploaded.

Data for 20061101-20061127 have been reprocessed with the revised calibrations and are 
available from the ARM Archive effective January 2007.

• Level of free convection pressure(levelFreeConvectionPres)
• Lifting condensation level(liftingCondensationLevel)
• Lifting condensation level pressure(liftingCondensationLevelPres)
• Level of free convection(levelFreeConvection)
• Derived relative humidity(relativeHumidity)
• Retrieved cloud liquid water content(liquidWaterContent)
• Retrieved liquid water path using only 23.835 and 30.0 GHz(liquidWaterPath2)
• Convective Available Potential Energy(cape)
• Interpolated dewpoint temperature(dewpointTemperature)
• Total precipitable water vapor, from microwave radiometer(totalPrecipitableWater)
• Retrieved water vapor density(waterVaporDensity)
• Retrieved liquid water path(liquidWaterPath)
• Microwave brightness temperature(brightnessTemperature)
• Interpolated water vapor mixing ratio(waterVaporMixingRatio)
• Retrieved total precipitable water vapor using only 23.835 and 30.0 GHz(totalPrecipitableWater2)

NSA/SONDE/C1 - Incorrect surface RH value

For an unknown reason the surface RH was reported a 0%.  Becuase these values are entered 
automatically by the system, this is NOT likely an operator error.  Examination of the 
raw data shows that the surface RH at launch time was approximately 81.2 %RH.

• Surface dew point temperature(dp)
• Relative humidity inside the instrument enclosure(rh)

NSA/MWRP/C1 - Incorrect surface measurements

Surface measurements are spiking and not comparing well with the co-located METTWR 
measurements.

On 2/13 site operators cleaned a filter in the heater housing resolving the problem.

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

NSA/SONDE/C1 - Temperature sensor broke at launch

The temperature sensor on this sonde broke at launch.  As a result all the thermodynamic 
data are incorrect.  The wind data are OK, though there will be some uncertainty in the 
altitude values.  This sounding was done at a non-standard time and it isn't clear whether 
it was delayed for some reason or a RHUBC sounding.  In either case, there is no fix.

• Dummy altitude for Zeb(alt)
• Dry bulb temperature(tdry)
• Surface dew point temperature(dp)
• Relative humidity inside the instrument enclosure(rh)
• Ascent Rate(asc)

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.

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

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.

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

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

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

The LN2 calibration on 3/15 showed a large drift of the V-band calibration parameters. The 
radiometer was calibrated again in June and was sent out for repairs in July 2007.

Between 3/15 and 7/13 2007 the V-band data are incorrect and should be disregarded. The 
failure affects the retrieved vertical profiles of temperature and humidity as well.

Please note that the hardware failure affected the 7 V-band channels only (51-60 GHz). 
Channels in the frequency range between 20 and 30 GHz are not affected. Integrated liquid 
water (LWP) and water vapor (PWV) are not affected since they use K-band channels only.

• Derived virtual temperature(virtualTemperature)
• air temperature (NGM250 predicted)(temperature)
• Retrieved water vapor density(waterVaporDensity)
• Derived relative humidity(relativeHumidity)
• Microwave brightness temperature(brightnessTemperature)
• Interpolated water vapor mixing ratio(waterVaporMixingRatio)