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/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/SKYRAD/M1 - IRT bias

The sky temperatures exhibited a positive bias compared to AERI, especially when < 230K. 
This is indicative of an incorrect emissivity setting (to compensate for the gold mirror) 
or a poor calibration. A similar problem with the same instrument occurred during the FKB 
deployment that was attributed to water vapor.

• Sky Infra Red Temperature Minima(sky_ir_temp_min)
• Sky Infra-Red Temperature(sky_ir_temp)
• Sky Infra Red Temperature Maxima(sky_ir_temp_max)

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/MWRP/M1 - Reprocess: Bias in LWP retrievals

Since local radiosondes were not available, radiosondes from a different site were used to 
develop retrieval coefficients. LWP retrievals are biased in the summer months 
(June-September).  Data in May and December are not affected.

Additional analysis will be conducted to derive new retrieval coefficients and the data 
will be reprocessed.

• Retrieved liquid water path(liquidWaterPath)
• Retrieved liquid water path using only 23.835 and 30.0 GHz(liquidWaterPath2)

HFE/MFRSR/M1 - Shading problem

It looks like there could be a shading problem beginning on 20080826 that lasts until 
20081013.  Affected data range from sunrise until about 0400 UTC.

• Nominal calibration factor, applied to filter6 data(nominal_calibration_factor_filter6)
• Narrowband Hemispheric Irradiance, Filter 1(hemisp_narrowband_filter1)
• cosine correction, south to north, filter5(cosine_correction_sn_filter5)
• Ratio of direct_normal_narrowband_filter3 to diffuse_hemisp_narrowband_filter3(direct_diffuse_ratio_filter3)
• Ratio of direct_normal_narrowband_filter4 to diffuse_hemisp_narrowband_filter4(direct_diffuse_ratio_filter4)
• Ratio of direct_normal_broadband to diffuse_hemisp_broadband(direct_diffuse_ratio_broadband)
• cosine correction, west to east, filter6(cosine_correction_we_filter6)
• Logger panel temperature(logger_temp)
• Normalized filter function data, filter 6, measured transmittance value obtained
  during bench calibrations(normalized_transmittance_filter6)
• Cosine correction applied to direct_horizontal_narrowband_filter3(computed_cosine_correction_filter3)
• time(time)
• Nominal calibration factor, applied to filter5 data(nominal_calibration_factor_filter5)
• Ratio of direct_normal_narrowband_filter2 to diffuse_hemisp_narrowband_filter2(direct_diffuse_ratio_filter2)
• lat(lat)
• Ratio of direct_normal_narrowband_filter5 to diffuse_hemisp_narrowband_filter5(direct_diffuse_ratio_filter5)
• cosine correction, south to north, filter1(cosine_correction_sn_filter1)
• Normalized filter function data, filter 3, wavelength value obtained during
  bench calibrations(wavelength_filter3)
• Cosine correction applied to direct_horizontal_narrowband_filter5(computed_cosine_correction_filter5)
• Alltime Narrowband Hemispheric Irradiance, Filter 5(alltime_hemisp_narrowband_filter5)
• Offset subtracted from upwelling hemispheric broadband data(offset_broadband)
• Normalized filter function data, filter 5, measured transmittance value obtained
  during bench calibrations(normalized_transmittance_filter5)
• Cosine correction applied to direct_horizontal_narrowband_filter2(computed_cosine_correction_filter2)
• Normalized filter function data, filter 6, wavelength value obtained during
  bench calibrations(wavelength_filter6)
• Alltime Narrowband Hemispheric Irradiance, Filter 6(alltime_hemisp_narrowband_filter6)
• Narrowband Diffuse Hemispheric Irradiance, Filter 5(diffuse_hemisp_narrowband_filter5)
• Normalized filter function data, filter 5, wavelength value obtained during
  bench calibrations(wavelength_filter5)
• base time(base_time)
• cosine correction, south to north, filter3(cosine_correction_sn_filter3)
• Direct Normal Narrowband Irradiance, Filter 6(direct_normal_narrowband_filter6)
• Alltime Narrowband Hemispheric Irradiance, Filter 4(alltime_hemisp_narrowband_filter4)
• Normalized filter function data, filter 4, measured transmittance value obtained
  during bench calibrations(normalized_transmittance_filter4)
• lon(lon)
• Narrowband Direct Horizontal Irradiance, Filter 1(direct_horizontal_narrowband_filter1)
• cosine correction, west to east, filter3(cosine_correction_we_filter3)
• Nominal calibration factor, applied to broadband data(nominal_calibration_factor_broadband)
• Normalized filter function data, filter 1, measured transmittance value obtained
  during bench calibrations(normalized_transmittance_filter1)
• Normalized filter function data, filter 1, wavelength value obtained during
  bench calibrations(wavelength_filter1)
• Narrowband Direct Horizontal Irradiance, Filter 2(direct_horizontal_narrowband_filter2)
• Cosine correction of filter6 diffuse, assuming Rayleigh sky at 45 deg zenith
  angle(diffuse_correction_filter6)
• Narrowband Diffuse Hemispheric Irradiance, Filter 1(diffuse_hemisp_narrowband_filter1)
• Narrowband Direct Horizontal Irradiance, Filter 3(direct_horizontal_narrowband_filter3)
• Solar zenith angle(solar_zenith_angle)
• Normalized filter function data, filter 3, measured transmittance value obtained
  during bench calibrations(normalized_transmittance_filter3)
• Narrowband Diffuse Hemispheric Irradiance, Filter 4(diffuse_hemisp_narrowband_filter4)
• Direct Normal Broadband Irradiance broadband scale applied(direct_normal_broadband)
• Direct Normal Narrowband Irradiance, Filter 3(direct_normal_narrowband_filter3)
• Cosine of Solar Zenith Angle(cosine_solar_zenith_angle)
• cosine correction, west to east, filter4(cosine_correction_we_filter4)
• Offset subtracted from upwelling hemispheric filter5 data(offset_filter5)
• Alltime Narrowband Hemispheric Irradiance, Filter 1(alltime_hemisp_narrowband_filter1)
• cosine correction, west to east, filter2(cosine_correction_we_filter2)
• Cosine correction of broadband diffuse, assuming Rayleigh sky at 45 deg zenith
  angle(diffuse_correction_broadband)
• cosine correction, south to north, filter6(cosine_correction_sn_filter6)
• Narrowband Diffuse Hemispheric Irradiance, Filter 6(diffuse_hemisp_narrowband_filter6)
• Direct Normal Narrowband Irradiance, Filter 5(direct_normal_narrowband_filter5)
• Narrowband Hemispheric Irradiance, Filter 2(hemisp_narrowband_filter2)
• Normalized filter function data, filter 4, wavelength value obtained during
  bench calibrations(wavelength_filter4)
• Ratio of direct_normal_narrowband_filter6 to diffuse_hemisp_narrowband_filter6(direct_diffuse_ratio_filter6)
• Normalized filter function data, filter 2, measured transmittance value obtained
  during bench calibrations(normalized_transmittance_filter2)
• cosine correction, south to north, broadband channel(cosine_correction_sn_broadband)
• Normalized filter function data, filter 2, wavelength value obtained during
  bench calibrations(wavelength_filter2)
• Offset subtracted from upwelling hemispheric filter6 data(offset_filter6)
• Cosine correction applied to direct_horizontal_narrowband_filter6(computed_cosine_correction_filter6)
• Diffuse Hemispheric Broadband Irradiance (Approximate), MFRSR(diffuse_hemisp_broadband)
• Narrowband Diffuse Hemispheric Irradiance, Filter 3(diffuse_hemisp_narrowband_filter3)
• Direct Normal Narrowband Irradiance, Filter 4(direct_normal_narrowband_filter4)
• Offset subtracted from upwelling hemispheric filter1 data(offset_filter1)
• Detector Temperature(head_temp)
• Cosine correction applied to direct_horizontal_narrowband_filter1(computed_cosine_correction_filter1)
• Narrowband Diffuse Hemispheric Irradiance, Filter 2(diffuse_hemisp_narrowband_filter2)
• Second Detector Temperature(head_temp2)
• Direct Normal Narrowband Irradiance, Filter 1(direct_normal_narrowband_filter1)
• Direct Normal Narrowband Irradiance, Filter 2(direct_normal_narrowband_filter2)
• Offset subtracted from upwelling hemispheric filter2 data(offset_filter2)
• Air mass(airmass)
• Narrowband Direct Horizontal Irradiance, Filter 5(direct_horizontal_narrowband_filter5)
• Cosine correction of filter2 diffuse, assuming Rayleigh sky at 45 deg zenith
  angle(diffuse_correction_filter2)
• cosine correction, west to east, broadband channel(cosine_correction_we_broadband)
• Nominal calibration factor, applied to filter2 data(nominal_calibration_factor_filter2)
• Nominal calibration factor, applied to filter1 data(nominal_calibration_factor_filter1)
• Hemispheric Irradiance, MFRSR(hemisp_broadband)
• Cosine correction of filter5 diffuse, assuming Rayleigh sky at 45 deg zenith
  angle(diffuse_correction_filter5)
• cosine correction, west to east, filter1(cosine_correction_we_filter1)
• Alltime Narrowband Hemispheric Irradiance, Filter 2(alltime_hemisp_narrowband_filter2)
• Narrowband Direct Horizontal Irradiance, Filter 4(direct_horizontal_narrowband_filter4)
• Alltime Hemispheric Broadband Irradiance(alltime_hemisp_broadband)
• Elevation Angle(elevation_angle)
• Azimuth angle(azimuth_angle)
• Alltime Narrowband Hemispheric Irradiance, Filter 3(alltime_hemisp_narrowband_filter3)
• cosine correction, south to north, filter2(cosine_correction_sn_filter2)
• Cosine correction applied to direct_horizontal_narrowband_filter4(computed_cosine_correction_filter4)
• cosine correction, west to east, filter5(cosine_correction_we_filter5)
• Cosine correction applied to direct_horizontal_broadband(computed_cosine_correction_broadband)
• Cosine correction of filter3 diffuse, assuming Rayleigh sky at 45 deg zenith
  angle(diffuse_correction_filter3)
• Ratio of direct_normal_narrowband_filter1 to diffuse_hemisp_narrowband_filter1(direct_diffuse_ratio_filter1)
• Nominal calibration factor, applied to filter3 data(nominal_calibration_factor_filter3)
• Narrowband Hemispheric Irradiance, Filter 3(hemisp_narrowband_filter3)
• Narrowband Direct Horizontal Irradiance, Filter 6(direct_horizontal_narrowband_filter6)
• Cosine correction of filter1 diffuse, assuming Rayleigh sky at 45 deg zenith
  angle(diffuse_correction_filter1)
• angle of incidence during cosine bench measurements(bench_angle)
• Time offset of tweaks from base_time(time_offset)
• Offset subtracted from upwelling hemispheric filter4 data(offset_filter4)
• Narrowband Hemispheric Irradiance, Filter 6(hemisp_narrowband_filter6)
• Narrowband Hemispheric Irradiance, Filter 5(hemisp_narrowband_filter5)
• Cosine correction of filter4 diffuse, assuming Rayleigh sky at 45 deg zenith
  angle(diffuse_correction_filter4)
• Offset subtracted from upwelling hemispheric filter3 data(offset_filter3)
• Direct Horizontal Broadband Irradiance, broadband scale applied(direct_horizontal_broadband)
• Data Logger Supply Voltage(logger_volt)
• Dummy altitude for Zeb(alt)
• Nominal calibration factor, applied to filter4 data(nominal_calibration_factor_filter4)
• Narrowband Hemispheric Irradiance, Filter 4(hemisp_narrowband_filter4)
• cosine correction, south to north, filter4(cosine_correction_sn_filter4)

• Logger panel temperature(logger_temp)
• Diffuse Narrowband Hemispheric Irradiance, Filter 5(diffuse_hemisp_narrowband_filter5_raw)
• Offset subtracted from upwelling hemispheric broadband data(offset_broadband)
• Diffuse Narrowband Hemispheric Irradiance, Filter 2(diffuse_hemisp_narrowband_filter2_raw)
• Narrowband Hemispheric Irradiance, Filter 2(hemisp_narrowband_filter2)
• Diffuse Narrowband Hemispheric Irradiance, Filter 4(diffuse_hemisp_narrowband_filter4_raw)
• base time(base_time)
• Narrowband Diffuse Hemispheric Irradiance, Filter 6(diffuse_hemisp_narrowband_filter6)
• Narrowband Direct Horizontal Irradiance, Filter 2(direct_horizontal_narrowband_filter2)
• Detector Temperature(head_temp)
• Alltime Narrowband Hemispheric Irradiance, Filter 3(alltime_hemisp_narrowband_filter3)
• Hemispheric Irradiance, MFRSR(hemisp_broadband)
• Alltime Narrowband Hemispheric Irradiance, Filter 2(alltime_hemisp_narrowband_filter2)
• Offset subtracted from upwelling hemispheric filter6 data(offset_filter6)
• Narrowband Hemispheric Irradiance, Filter 1(hemisp_narrowband_filter1)
• Narrowband Diffuse Hemispheric Irradiance, Filter 1(diffuse_hemisp_narrowband_filter1)
• Narrowband Hemispheric Irradiance, Filter 4(hemisp_narrowband_filter4_raw)
• Offset subtracted from upwelling hemispheric filter5 data(offset_filter5)
• Narrowband Hemispheric Irradiance, Filter 2(hemisp_narrowband_filter2_raw)
• Second Detector Temperature(head_temp2)
• Narrowband Hemispheric Irradiance, Filter 3(hemisp_narrowband_filter3_raw)
• Alltime Hemispheric Broadband Irradiance(alltime_hemisp_broadband)
• lon(lon)
• Narrowband Hemispheric Irradiance, Filter 3(hemisp_narrowband_filter3)
• Alltime Narrowband Hemispheric Irradiance, Filter 4(alltime_hemisp_narrowband_filter4)
• Alltime Narrowband Hemispheric Irradiance, Filter 5(alltime_hemisp_narrowband_filter5)
• Alltime Narrowband Hemispheric Irradiance, Filter 1(alltime_hemisp_narrowband_filter1)
• Diffuse Narrowband Hemispheric Irradiance, Filter 6(diffuse_hemisp_narrowband_filter6_raw)
• Narrowband Direct Horizontal Irradiance, Filter 6(direct_horizontal_narrowband_filter6)
• Narrowband Diffuse Hemispheric Irradiance, Filter 2(diffuse_hemisp_narrowband_filter2)
• Narrowband Direct Horizontal Irradiance, Filter 3(direct_horizontal_narrowband_filter3)
• Offset subtracted from upwelling hemispheric filter2 data(offset_filter2)
• Narrowband Direct Horizontal Irradiance, Filter 4(direct_horizontal_narrowband_filter4)
• time(time)
• Narrowband Hemispheric Irradiance, Filter 5(hemisp_narrowband_filter5)
• Alltime Narrowband Hemispheric Irradiance, Filter 6(alltime_hemisp_narrowband_filter6)
• Narrowband Direct Horizontal Irradiance, Filter 5(direct_horizontal_narrowband_filter5)
• Narrowband Hemispheric Irradiance, Filter 6(hemisp_narrowband_filter6)
• Hemispheric Broadband Irradiance(hemisp_broadband_raw)
• Narrowband Diffuse Hemispheric Irradiance, Filter 4(diffuse_hemisp_narrowband_filter4)
• Narrowband Diffuse Hemispheric Irradiance, Filter 3(diffuse_hemisp_narrowband_filter3)
• Dummy altitude for Zeb(alt)
• Narrowband Diffuse Hemispheric Irradiance, Filter 5(diffuse_hemisp_narrowband_filter5)
• Data Logger Supply Voltage(logger_volt)
• Diffuse Hemispheric Broadband Irradiance (Approximate), MFRSR(diffuse_hemisp_broadband)
• Narrowband Direct Horizontal Irradiance, Filter 1(direct_horizontal_narrowband_filter1)
• Narrowband Hemispheric Irradiance, Filter 6(hemisp_narrowband_filter6_raw)
• Diffuse Narrowband Hemispheric Irradiance, Filter 3(diffuse_hemisp_narrowband_filter3_raw)
• Narrowband Hemispheric Irradiance, Filter 1(hemisp_narrowband_filter1_raw)
• Offset subtracted from upwelling hemispheric filter3 data(offset_filter3)
• Narrowband Hemispheric Irradiance, Filter 4(hemisp_narrowband_filter4)
• Diffuse Narrowband Hemispheric Irradiance, Filter 1(diffuse_hemisp_narrowband_filter1_raw)
• Offset subtracted from upwelling hemispheric filter1 data(offset_filter1)
• Time offset of tweaks from base_time(time_offset)
• Diffuse Hemispheric Broadband Irradiance(diffuse_hemisp_broadband_raw)
• lat(lat)
• Offset subtracted from upwelling hemispheric filter4 data(offset_filter4)
• Direct Horizontal Broadband Irradiance, broadband scale applied(direct_horizontal_broadband)
• Narrowband Hemispheric Irradiance, Filter 5(hemisp_narrowband_filter5_raw)

• null(Raw data stream - documentation not supported)

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)