FKB/MWRP/M1 - Reprocess: Incorrect calibration

The software was started with the wrong calibration data.

• Retrieved liquid water path(liquidWaterPath)
• Retrieved cloud liquid water content(liquidWaterContent)
• Retrieved total precipitable water vapor using only 23.835 and 30.0 GHz(totalPrecipitableWater2)
• air temperature (NGM250 predicted)(temperature)
• Interpolated water vapor mixing ratio(waterVaporMixingRatio)
• Lifting condensation level(liftingCondensationLevel)
• Derived relative humidity(relativeHumidity)
• Total precipitable water vapor, from microwave radiometer(totalPrecipitableWater)
• Lifting condensation level pressure(liftingCondensationLevelPres)
• Derived virtual temperature(virtualTemperature)
• Level of free convection(levelFreeConvection)
• Microwave brightness temperature(brightnessTemperature)
• Expected root-mean-square error in liquid water path retrieval using only 23.835
  and 30.0 GHz(liquidWaterPath2RmsError)
• Retrieved liquid water path using only 23.835 and 30.0 GHz(liquidWaterPath2)
• Retrieved water vapor density(waterVaporDensity)
• Level of free convection pressure(levelFreeConvectionPres)
• Expected root-mean-square error in liquid water content retrieval(liquidWaterContentRmsError)
• Expected root-mean-square error in liquid water path retrieval(liquidWaterPathRmsError)

FKB/MWRP/M1 - LN2 Calibration-

Between 1100 and 1500 there were two calibration attempts.

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

FKB/MWRP/M1 - Reprocessed: Updated 30-GHz calibration coefficient

On 9/17 the instrument was calibrated with liquid nitrogen. For the 30-GHz channel the 
results of calibration were not optimal and were causing a negative bias in the retrieved 
LWP.

On 10/9 the 30-GHz calibration parameters were updated with values derived from tip 
curves.

Data between 9/17 and 10/9 were reprocessed to correct the 30-GHz calibration.  
Reprocessed data were archived 20080122.

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

FKB/MWRP/M1 - Heavy rain and fog at the site

The months of November and December have been very rainy and wet at the AMF site. During 
rain events the radiometer does not work properly because of water accumulating on the 
window. In addition condensation and fog will affect the data causing very high brightness 
temperatures. Although the instrument is equipped with rain detection system to flag bad 
data, it is important that the user pays extra attention to the quality of the data during 
periods of continuous rain, drizzle or fog by applying the quality checks and screening 
for high brightness temperatures.

• Retrieved liquid water path(liquidWaterPath)
• Interpolated dewpoint temperature(dewpointTemperature)
• Retrieved cloud liquid water content(liquidWaterContent)
• Retrieved total precipitable water vapor using only 23.835 and 30.0 GHz(totalPrecipitableWater2)
• air temperature (NGM250 predicted)(temperature)
• Microwave brightness temperature(brightnessTemperature)
• Interpolated water vapor mixing ratio(waterVaporMixingRatio)
• Total precipitable water vapor, from microwave radiometer(totalPrecipitableWater)
• Derived relative humidity(relativeHumidity)
• Derived virtual temperature(virtualTemperature)
• Retrieved liquid water path using only 23.835 and 30.0 GHz(liquidWaterPath2)
• Retrieved water vapor density(waterVaporDensity)

FKB/MWRP/M1 - Possible slight drift of V-band calibration

During the month of November and December the bias between model computations and 
measurements for the 51.25 and 52.28 GHz channels has slightly increased to about 3 K. This might 
be due to a slight drift in the calibration of these channels.

The calibration error associated with these data is increased, to 2-3 K, for these two 
months. See this plot for a comparison of measurements (solid lines) and model (red 
dots) for the 51.25 (black), 52.28 (blue) and 53.85-GHz (green) channels.

• Microwave brightness temperature(brightnessTemperature)

FKB/MWRP/M1 - Periodic decrease in the 30-GHz brightness temperature

Starting around 12/19 until the end of December, the 30-GHz brightness temperature started 
to show a periodic oscillation between 9 and 11 AM GMT. The cause of this is probably 
thermal instability of the radiometer since it does correspond with some larger 
oscillations of the mixer temperature. During this time external temperatures displayed large 
variations going from -10 C at night to about +5 C during the day. The corresponding liquid 
water path retrievals are affected showing periodic negative values.

Liquid water path retrievals between 12/19 and 12/31 are the most affected variable since 
they are largely affected by the 30-GHz channel. A time series plot of the data will 
clearly show the periodic fluctuation of the LWP variable.

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

FKB/TSI/M1 - Reprocess: Missing time annotation

The time annotation in the MPeg movie is missing.

• (MPEG data stream - documentation not yet available)