HFE/MWR/M1 - Insufficient calibration stability

The noise diode temperature suddenly jumped to > 60 C after a power outage. Following 
additional power problems the noise diode injection temperature drifted fast and the 
radiometer was not able to calibrate properly.

Data during the indicated time periods are poorly calibrated and sometimes erratic. Users 
should be aware that the accuracy of the measurements is dramatically degraded. 

Users can use the microwave profiler (MWRP) data to supplement the MWR data.

• Sky brightness temperature at 31.4 GHz(tbsky31)
• Noise injection temp at nominal temperature at 31.4 GHz(tnd_nom31)
• Noise injection temp at 23.8 GHz adjusted to tkbb(tnd23)
• MWR column precipitable water vapor(vap)
• Temperature correction coefficient at 31.4 GHz(tc31)
• Temperature correction coefficient at 23.8 GHz(tc23)
• Noise injection temp at nominal temperature at 23.8 GHz(tnd_nom23)
• Averaged total liquid water along LOS path(liq)
• Mixer kinetic (physical) temperature(tkxc)
• (tknd)
• Sky brightness temperature at 23.8 GHz(tbsky23)
• Noise injection temp at 31.4 GHz adjusted to tkbb(tnd31)

• Noise injection temp at nominal temperature at 23.8 GHz(tnd_nom23)
• Noise injection temp at 31.4 GHz adjusted to tkbb(tnd31)
• Total water vapor along zenith path using tip-derived brightness temperatures(vaptip)
• Total liquid water along zenith path using tip-derived brightness temperatures(liqtip)
• Noise injection temp at 23.8 GHz derived from this tip(tnd23I)
• 23.8 GHz sky brightness temperature derived from tip curve(tbsky23tip)
• Temperature correction coefficient at 23.8 GHz(tc23)
• Mixer kinetic (physical) temperature(tkxc)
• Temperature correction coefficient at 31.4 GHz(tc31)
• 31.4 GHz sky brightness temperature derived from tip curve(tbsky31tip)
• Noise injection temp at 31.4 GHz derived from this tip(tnd31I)
• Noise injection temp at nominal temperature at 31.4 GHz(tnd_nom31)
• Noise injection temp at 23.8 GHz adjusted to tkbb(tnd23)
• (tknd)

HFE/MET/M1 -  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.

• Wind speed arithmetic average(wind_spd_arith_avg)
• Wind speed arithmetic maximum(wind_spd_arith_max)
• Wind speed arithmetic minimum(wind_spd_arith_min)
• Vector-averaged Wind Speed(wind_spd_vec_avg)
• Wind speed arithmetic standard deviation(wind_spd_arith_sd)

HFE/MWRHF/M1 - 150-GHz data drop out

The sky brightness temperature at 150 GHz (tbsky150) dropped to zero at 12:29 GMT on 
20080804 and stayed flat lined until 23:40 GMT on 20081002.

• Sky brightness temperature (150 GHz)(tbsky150)

HFE/AOS/M1 - No sub 1 micron data

The aerosol size switching impactors were stuck in the sub 10 micron mode. So all aerosol 
is sub 10 um.

• Aerosol backwards-hemispheric light scattering coefficient, red channel, 1 um
  size cut, wet three wavelength nephelometer(Bbs_R_Wet_1um_Neph3W_2)
• Aerosol backwards-hemispheric light scattering coefficient, blue channel, 1 um
  size cut, wet three wavelength nephelometer(Bbs_B_Wet_1um_Neph3W_2)
• Aerosol backwards-hemispheric light scattering coefficient, green channel, 1 um
  size cut, wet three wavelength nephelometer(Bbs_G_Wet_1um_Neph3W_2)
• Aerosol total light scattering coefficient, red channel, 1 um size cut,
  reference three wavelength nephelometer(Bs_R_Dry_1um_Neph3W_1)
• Absorption Coefficient Red, corrected for flow and sample area, 3 wavelength
  PSAP, 1 um size cut(Ba_R_Dry_1um_PSAP3W_1)
• Aerosol total light scattering coefficient, red channel, 1 um size cut, wet
  three wavelength nephelometer(Bs_R_Wet_1um_Neph3W_2)
• Aerosol backwards-hemispheric light scattering coefficient, green channel, 1 um
  size cut, reference three wavelength nephelometer(Bbs_G_Dry_1um_Neph3W_1)
• Aerosol total light scattering coefficient, green channel, 1 um size cut, wet
  three wavelength nephelometer(Bs_G_Wet_1um_Neph3W_2)
• Aerosol total light scattering coefficient, blue channel, 1 um size cut, wet
  three wavelength nephelometer(Bs_B_Wet_1um_Neph3W_2)
• Aerosol total light scattering coefficient, blue channel, 1 um size cut,
  reference three wavelength nephelometer(Bs_B_Dry_1um_Neph3W_1)
• Aerosol total light scattering coefficient, green channel, 1 um size cut,
  reference three wavelength nephelometer(Bs_G_Dry_1um_Neph3W_1)
• Aerosol backwards-hemispheric light scattering coefficient, red channel, 1 um
  size cut, reference three wavelength nephelometer(Bbs_R_Dry_1um_Neph3W_1)
• Absorption Coefficient Green, corrected for flow and sample area, 3 wavelength
  PSAP, 1 um size cut(Ba_G_Dry_1um_PSAP3W_1)
• Absorption Coefficient Blue, corrected for flow and sample area, 3 wavelength
  PSAP, 1 um size cut(Ba_B_Dry_1um_PSAP3W_1)
• Aerosol backwards-hemispheric light scattering coefficient, blue channel, 1 um
  size cut, reference three wavelength nephelometer(Bbs_B_Dry_1um_Neph3W_1)
• Aerosol light absorption coefficient, green channel, 1 um size cut(Ba_G_Dry_1um_PSAP1W_1)

HFE/AOS/M1 - Humidifier failure

The humidifier either wasn't scanning or the wet nephelometer was flooded with water.

• Aerosol total light scattering coefficient, red channel, 1 um size cut, wet
  three wavelength nephelometer(Bs_R_Wet_1um_Neph3W_2)
• Aerosol total light scattering coefficient, green channel, 1 um size cut, wet
  three wavelength nephelometer(Bs_G_Wet_1um_Neph3W_2)
• Aerosol backwards-hemispheric light scattering coefficient, red channel, 10 um
  size cut, wet three wavelength nephelometer(Bbs_R_Wet_10um_Neph3W_2)
• Aerosol backwards-hemispheric light scattering coefficient, red channel, 1 um
  size cut, wet three wavelength nephelometer(Bbs_R_Wet_1um_Neph3W_2)
• Aerosol backwards-hemispheric light scattering coefficient, blue channel, 1 um
  size cut, wet three wavelength nephelometer(Bbs_B_Wet_1um_Neph3W_2)
• Aerosol total light scattering coefficient, blue channel, 1 um size cut, wet
  three wavelength nephelometer(Bs_B_Wet_1um_Neph3W_2)
• Aerosol total light scattering coefficient, green channel, 10 um size cut, wet
  three wavelength nephelometer(Bs_G_Wet_10um_Neph3W_2)
• Aerosol backwards-hemispheric light scattering coefficient, green channel, 1 um
  size cut, wet three wavelength nephelometer(Bbs_G_Wet_1um_Neph3W_2)
• Aerosol backwards-hemispheric light scattering coefficient, green channel, 10 um
  size cut, wet three wavelength nephelometer(Bbs_G_Wet_10um_Neph3W_2)
• Aerosol total light scattering coefficient, blue channel, 10 um size cut, wet
  three wavelength nephelometer(Bs_B_Wet_10um_Neph3W_2)
• Aerosol total light scattering coefficient, red channel, 10 um size cut, wet
  three wavelength nephelometer(Bs_R_Wet_10um_Neph3W_2)
• Aerosol backwards-hemispheric light scattering coefficient, blue channel, 10 um
  size cut, wet three wavelength nephelometer(Bbs_B_Wet_10um_Neph3W_2)

HFE/AOS/M1 - CPC data missing

The CPC wasn't installed until July 22nd when the mentor visited the site.

• Condensation Nuclei Concentration Number(N_CPC_1)

HFE/AOS/M1 - CCN missing

A power regulator on the CCN circuit board failed. The mentor replaced it and it was up 
and working on 7/25/2008.

• AOS CCN temperature at middle of column(CCN_T_TEC2)
• Size of upper limit of each CCN bin(CCN_UpperSizeLimit)
• AOS bin number of lowest channel of OPC include in summation of N_CCN(N_CCN_bin_number)
• AOS CCN temperature of the optical particle counter(CCN_T_OPC)
• AOS CCN volumetric flowrate of sample air(CCN_Q_sample)
• AOS CCN temperature of sample air at entrance to instrument(CCN_T_inlet)
• AOS CCN temperature of the nafion humidifier(CCN_T_nafion)
• AOS CCN temperature at bottom of column(CCN_T_TEC3)
• CCN Propotional valve voltage(CCN_ProportionalValveVoltage)
• AOS CCN sample pressure(CCN_P_sample)
• AOS CCN sample supersaturation calculated by model)(CCN_ss_calc)
• CCN temperature gradient(CCN_Temperature_Gradient)
• Hexadecimal flag, non-zero value means instrument is not operating stably(CCN_temp_unstable_flag)
• AOS CCN temperature of sample air entering the column(CCN_T_sample)
• AOS CCN volumetric flowrate of sheath air(CCN_Q_sheath)
• AOS CCN standard deviation of difference (CCN_T_TEC1 - CCN_T_TEC3)(CCN_dT_TEC3_TEC1_StdDev)
• First stage monitor voltage(CCN_FirstStageMonitorVoltage)
• AOS CCN temperature at top of column(CCN_T_TEC1)
• AOS CCN OPC laser current(CCN_laser_current)
• AOS number concentration of CCN(N_CCN)
• AOS CCN sample saturation setpoint value reported by instrument(CCN_ss_set)
• AOS CCN number concentration by bin(N_CCN_dN)

HFE/AOS/M1 - PSAP data missing

The PSAP was disconnected during this time period.

• Absorption Coefficient Red, corrected for flow and sample area, 3 wavelength
  PSAP, 1 um size cut(Ba_R_Dry_1um_PSAP3W_1)
• Aerosol light absorption coefficient, green channel, 10 um size cut(Ba_G_Dry_10um_PSAP1W_1)
• Absorption Coefficient Green, corrected for flow and sample area, 3 wavelength
  PSAP, 1 um size cut(Ba_G_Dry_1um_PSAP3W_1)
• Absorption Coefficient Blue, corrected for flow and sample area, 3 wavelength
  PSAP, 1 um size cut(Ba_B_Dry_1um_PSAP3W_1)
• Absorption Coefficient Green, corrected for flow and sample area, 3 wavelength
  PSAP, 10 um size cut(Ba_G_Dry_10um_PSAP3W_1)
• Aerosol light absorption coefficient, green channel, 1 um size cut(Ba_G_Dry_1um_PSAP1W_1)
• Absorption Coefficient Blue, corrected for flow and sample area, 3 wavelength
  PSAP, 10 um size cut(Ba_B_Dry_10um_PSAP3W_1)
• Absorption Coefficient Red, corrected for flow and sample area, 3 wavelength
  PSAP, 10 um size cut(Ba_R_Dry_10um_PSAP3W_1)

HFE/MWRHF/M1 - Frosting/Condensation

The heater module was installed on 6/4/2008. Before this time there is condensation on the 
window during night time and early morning. On 8/18 the heater appears to have failed 
and nighttime condensation re-occurred on the radome during conditions of high humidity.

Users can identify the segments affected by observing a smooth steady increase in the 
brightness temperature (BT). BT values can increase to more than 250 K and then smoothly 
decrease. The RH during these events is usually above 70%. Users should disregard data 
affected by condensation.

• Sky brightness temperature (150 GHz)(tbsky150)
• Sky brightness temperature (90 GHz)(tbsky90)

HFE/MWRHF/M1 - Calibration updates

The MWRHF calibration algorithm updates the calibration parameters every time a new 
successful tip curve is acquired. 

This results in small jumps (1-2 K) in the brightness temperatures each time calibration 
is updated. During times of frequent calibrations the data appear discontinuous with short 
data segments interrupted by small jumps.

• Sky brightness temperature (150 GHz)(tbsky150)
• Sky brightness temperature (90 GHz)(tbsky90)

HFE/MWRHF/M1 - Rain sensor failure

The rain sensor failed and the rain flag was always on.  When the rain flag is on the 
radiometer does not perform tip curves. The rain sensor was replaced 8/4.

• Rain flag(rain_flag)

HFE/MET/M1 - Intermittent barometer failure

Intermittent barometer failure occurred throughout the deployment.  We were unable to 
pinpoint the cause of the failure.  Typically one or two minutes of missing data occurred 
every few days.

Since pressure data is typically invariant over 1 minute, linear interpolation should be 
fine to fill in missing data.

• Barometric Pressure(atmos_pressure)

HFE/MET/M1 - Intermittent PWD data

The Present Weather Detector had intermittent missing values throughout this deployment.  
Missing values occurred almost everyday, usually just one or two minutes per day.

• 1 minute average water intensity(pwd_avg_H2O_int_1_min)
• 15 min present weather code(pwd_pw_code_15_min)
• Average 10 min visibility(pwd_avg_vis_10_min)
• Average 1 min visibility(pwd_avg_vis_1_min)
• 1 hour present weather code(pwd_pw_code_1_hr)
• Instantaneous present weather code(pwd_pw_code_inst)
• Cumulative water(pwd_cumul_water)
• Present weather detector error code(pwd_err_code)
• Present weather detector ID(pwd_id)
• Cumulative snow(pwd_cumul_snow)

HFE/MET/M1 - ORG Measuring Ice Crystals or Fog

The ORG was measuring consistent values for long periods of time.  Typically this is 
indicative of fog, ice crystals in the air or poor performance of the lens heaters.

• Precipitation rate standard deviation(precip_rate_sd)
• Precipitation rate minimum(precip_rate_min)
• Precipitation rate mean(precip_rate_mean)
• Precipitation rate maximum(precip_rate_max)

HFE/MET/M1 - Induced voltage on wind speed sensor cable

The cable for the wind monitor is not a twisted pair shielded cable.  This caused an 
induced voltage on the wind sensor wires from the wind direction measurement excitation 
voltage.  A small offset is added into the wind speeds.  This value varies.  Most frequently 
the values of 0.49, 0.588 and 0.686 m/s were added into the wind speed.  On 11/27/2008 the 
value jumped to 0.98 m/s for most of the day.

• Wind speed arithmetic average(wind_spd_arith_avg)
• Wind speed arithmetic maximum(wind_spd_arith_max)
• Wind speed arithmetic minimum(wind_spd_arith_min)
• Vector-averaged Wind Speed(wind_spd_vec_avg)
• Wind speed arithmetic standard deviation(wind_spd_arith_sd)

HFE/MWRHF/M1 - Elevated noise in 150 GHz data

The noise level of the 150 GHz channel was about 4 times higher than expected, likely due 
to failure of the noise diode.  Disregard the 150 GHz data.

• Sky brightness temperature (150 GHz)(tbsky150)

HFE/MWR/M1 - Missing data

Data are missing and unrecoverable.

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

• 31.4 GHz goodness-of-fit coefficient(r31)
• 31.4 GHz sky signal(tipsky31)
• Noise injection temp at 23.8 GHz derived from this tip(tnd23I)
• Mixer kinetic (physical) temperature(tkxc)
• 31.4 GHz sky brightness temperature derived from tip curve(tbsky31tip)
• Ambient temperature(tkair)
• Time offset of tweaks from base_time(time_offset)
• Noise injection temp at nominal temperature at 31.4 GHz(tnd_nom31)
• Actual Azimuth(actaz)
• Water on Teflon window (1=WET, 0=DRY)(wet_window)
• 23.8 GHz blackbody+noise injection signal(bbn23)
• time(time)
• Blackbody kinetic temperature(tkbb)
• Noise injection temp at nominal temperature at 23.8 GHz(tnd_nom23)
• Noise injection temp at 31.4 GHz adjusted to tkbb(tnd31)
• Total water vapor along zenith path using tip-derived brightness temperatures(vaptip)
• 23.8 GHz goodness-of-fit coefficient(r23)
• Total liquid water along zenith path using tip-derived brightness temperatures(liqtip)
• 23.8 GHz sky brightness temperature derived from tip curve(tbsky23tip)
• base time(base_time)
• Temperature correction coefficient at 23.8 GHz(tc23)
• Temperature correction coefficient at 31.4 GHz(tc31)
• lon(lon)
• Noise injection temp at 31.4 GHz derived from this tip(tnd31I)
• 31.4 GHz blackbody(bb31)
• Noise injection temp at 23.8 GHz adjusted to tkbb(tnd23)
• 31.4 GHz blac2body+noise injection signal(bbn31)
• Dummy altitude for Zeb(alt)
• (tknd)
• Actual elevation angle(actel)
• 23.8 GHz Blackbody signal(bb23)
• lat(lat)
• 23.8 GHz sky signal(tipsky23)