TWP/MWR/C3 - Sun in field of view of radiometer

Each day from approximately 10/15 to 11/9 around local noon, there is an increase in the 
brightness temperature due to the sun being in the field of view of the radiometer.

• MWR column precipitable water vapor(vap)
• Averaged total liquid water along LOS path(liq)
• Sky brightness temperature at 31.4 GHz(tbsky31)
• Sky brightness temperature at 23.8 GHz(tbsky23)

• 31.8 GHz sky brightness temperature derived from tip curve(tbskytip31)
• Total water vapor along zenith path using tip-derived brightness temperatures(vaptip)
• Total liquid water along zenith path using tip-derived brightness temperatures(liqtip)
• 23.8 GHz sky signal(tipsky23)
• 31.4 GHz sky signal(tipsky31)
• 23.8 GHz sky brightness temperature derived from tip curve(tbskytip23)

TWP/MWR/C1/C2 - Sun in the field of view

Every day between around noon local time (usually between 1 and 2 AM UTC time) there is an 
increase in the brightness temperatures due to the sun in the field of view of the 
radiometer.

• 31.4 GHz sky signal(sky31)
• Sky brightness temperature at 23.8 GHz(tbsky23)
• MWR column precipitable water vapor(vap)
• 23.8 GHz sky signal(sky23)
• Sky brightness temperature at 31.4 GHz(tbsky31)
• Averaged total liquid water along LOS path(liq)

• MWR column precipitable water vapor(vap)
• 31.4 GHz sky signal(sky31)
• Sky brightness temperature at 23.8 GHz(tbsky23)
• Sky brightness temperature at 31.4 GHz(tbsky31)
• Averaged total liquid water along LOS path(liq)
• 23.8 GHz sky signal(sky23)

• 23.8 GHz sky brightness temperature derived from tip curve(tbskytip23)
• 31.8 GHz sky brightness temperature derived from tip curve(tbskytip31)
• Total liquid water along zenith path using tip-derived brightness temperatures(liqtip)
• Total water vapor along zenith path using tip-derived brightness temperatures(vaptip)

• 31.4 GHz sky signal(tipsky31)
• 23.8 GHz sky signal(tipsky23)

TWP/SMET/C2 - Wind Speed data contain offset due to induced voltage

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.

• Upper sensor, wind speed vector average(up_spd_vec_avg)
• Upper sensor, wind speed minimum(up_spd_min)
• Lower sensor, wind speed minimum(lo_spd_min)
• Upper sensor, wind speed maximum(up_spd_max)
• Lower sensor, wind speed arithmetic average(lo_spd_arith_avg)
• Lower sensor, wind speed maximum(lo_spd_max)
• Lower sensor, wind speed vector average(lo_spd_vec_avg)
• Lower sensor, wind speed standard deviation(lo_spd_sd)
• Upper sensor, wind speed arithmetic average(up_spd_arith_avg)
• Upper sensor, wind speed standard deviation(up_spd_sd)

TWP/MWR/C2 - Incorrect ambient temperature during rain

The ambient temperature was approximately 15 degree higher than what it should be when it 
was raining and the heater came. On Jan 9 2009 the dewblower was replaced which solved 
the problem.

The increased ambient temperature (tkair) was happening during times of rain and users 
should always disregard MWR data during rain events.  Therefore this DQR is colored 
transparent.

• Ambient temperature(tkair)

• Ambient temperature(tkair)

TWP/MWR/C1 - Ambient temperature data missing

The ambient temperature readings (tkair) suddenly failed. The sensor was replaced on Feb 
6.

• Ambient temperature(tkair)

• Ambient temperature(tkair)

TWP/SMET/C3 - Reprocess: Station Pressure values reported in hPa instead of kPa.

An incorrect program was entered into the datalogger.  This program did not convert the 
station pressure from hPa to kPa.  This made the values larger by a factor of 10 and caused 
the QC bit to be tripped.

• Barometric Pressure(atmos_pressure)

TWP/SONDE/C2 - Suspect RH values

RH values only are suspect for the duration of this radiosonde flight, exhibiting a 
"sawtooth" pattern.

• Relative humidity inside the instrument enclosure(rh)

TWP/SMET/C1 - Optical Rain Gage Inoperative

Beginning on 02/07/2009, the trending between the TBRG and ORG began to look poor, one 
recording precip when the other was not and vice versa.  After a while the ORG quit 
registering any precip at all.  ORG was replaced.

• Precipitation mean(precip_mean)
• Precipitation maximum(precip_max)
• Precipitation standard deviation(precip_sd)
• precipitation minimum(precip_min)

TWP/MWR/C2 - Intermittent data

There are several short data gaps (usually 2 to 7 hours) in the data due to computer 
malfunction. The problem was solved by replacing the computer.

• 31.4 GHz sky signal(sky31)
• Noise injection temp at 31.4 GHz adjusted to tkbb(tnd31)
• Mixer kinetic (physical) temperature(tkxc)
• 23.8 GHz blackbody+noise injection signal(bbn23)
• Blackbody kinetic temperature(tkbb)
• lat(lat)
• Water on Teflon window (1=WET, 0=DRY)(wet_window)
• Temperature correction coefficient at 23.8 GHz(tc23)
• Sky brightness temperature at 23.8 GHz(tbsky23)
• 31.4 GHz blackbody(bb31)
• MWR column precipitable water vapor(vap)
• 23.8 GHz sky signal(sky23)
• Ambient temperature(tkair)
• IR Brightness Temperature(ir_temp)
• base time(base_time)
• Noise injection temp at nominal temperature at 23.8 GHz(tnd_nom23)
• 31.4 GHz blac2body+noise injection signal(bbn31)
• Noise injection temp at 23.8 GHz adjusted to tkbb(tnd23)
• Sky brightness temperature at 31.4 GHz(tbsky31)
• Averaged total liquid water along LOS path(liq)
• Noise injection temp at nominal temperature at 31.4 GHz(tnd_nom31)
• lon(lon)
• 23.8 GHz Blackbody signal(bb23)
• (tknd)
• Actual Azimuth(actaz)
• Time offset of tweaks from base_time(time_offset)
• Actual elevation angle(actel)
• Dummy altitude for Zeb(alt)
• Sky Infra-Red Temperature(sky_ir_temp)
• Temperature correction coefficient at 31.4 GHz(tc31)

• 31.4 GHz sky signal(tipsky31)
• lat(lat)
• Noise injection temp at 31.4 GHz derived from this tip(tnd31I)
• 31.4 GHz goodness-of-fit coefficient(r31)
• Actual Azimuth(actaz)
• 23.8 GHz sky signal(tipsky23)
• 31.4 GHz blac2body+noise injection signal(bbn31)
• 31.4 GHz blackbody(bb31)
• Noise injection temp at nominal temperature at 23.8 GHz(tnd_nom23)
• Ambient temperature(tkair)
• Dummy altitude for Zeb(alt)
• (tknd)
• base time(base_time)
• Blackbody kinetic temperature(tkbb)
• Noise injection temp at 23.8 GHz adjusted to tkbb(tnd23)
• Noise injection temp at 31.4 GHz adjusted to tkbb(tnd31)
• Water on Teflon window (1=WET, 0=DRY)(wet_window)
• 23.8 GHz goodness-of-fit coefficient(r23)
• Time offset of tweaks from base_time(time_offset)
• Temperature correction coefficient at 23.8 GHz(tc23)
• Actual elevation angle(actel)
• Noise injection temp at nominal temperature at 31.4 GHz(tnd_nom31)
• 23.8 GHz Blackbody signal(bb23)
• Noise injection temp at 23.8 GHz derived from this tip(tnd23I)
• lon(lon)
• 23.8 GHz blackbody+noise injection signal(bbn23)
• Mixer kinetic (physical) temperature(tkxc)
• Temperature correction coefficient at 31.4 GHz(tc31)

TWP/SMET/C3 - Reprocess: Temperature Biased low by 1.06 Degrees

The temperature of the SMET system was biased low by 1.06 Deg C due to a non-precision 
resistor being used int he measurement circuit.  The data will be reprocessed.  Saturation 
Vapor pressure and Vapor pressure will have to be reprocessed also.

Add 1.06 degrees to the temperature data.  

Correct Sat Vap Press using the Buck approximation:
   Es = 6.1121exp((17.502*T)/(240.97 + T) 
where T is the temperature in C.  

Correct Vapor pressure using: E = (RH*Es)/100

• Vapor pressure standard deviation(vappress_sd)
• Mean Air Temperature or Hardware Error(temp_mean)
• Vapor pressure mean(vappress_mean)
• Std Dev of Air Temperature(temp_sd)