NSA/MWR/C2 - Missing data

Data are missing and unrecoverable.

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

• Blackbody kinetic temperature(tkbb)
• 31.8 GHz sky brightness temperature derived from tip curve(tbskytip31)
• Water on Teflon window (1=WET, 0=DRY)(wet_window)
• Noise injection temp at 23.8 GHz derived from this tip(tnd23I)
• Total water vapor along zenith path using tip-derived brightness temperatures(vaptip)
• lon(lon)
• Total liquid water along zenith path using tip-derived brightness temperatures(liqtip)
• Dummy altitude for Zeb(alt)
• 31.4 GHz blackbody(bb31)
• Actual Azimuth(actaz)
• Temperature correction coefficient at 23.8 GHz(tc23)
• 31.4 GHz sky signal(tipsky31)
• 23.8 GHz sky brightness temperature derived from tip curve(tbskytip23)
• Ambient temperature(tkair)
• 23.8 GHz blackbody+noise injection signal(bbn23)
• Noise injection temp at nominal temperature at 31.4 GHz(tnd_nom31)
• (tknd)
• 23.8 GHz goodness-of-fit coefficient(r23)
• Mixer kinetic (physical) temperature(tkxc)
• Noise injection temp at 23.8 GHz adjusted to tkbb(tnd23)
• 31.4 GHz blac2body+noise injection signal(bbn31)
• 23.8 GHz sky signal(tipsky23)
• Actual elevation angle(actel)
• lat(lat)
• 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 derived from this tip(tnd31I)
• 31.4 GHz goodness-of-fit coefficient(r31)
• Time offset of tweaks from base_time(time_offset)
• base time(base_time)
• 23.8 GHz Blackbody signal(bb23)
• Temperature correction coefficient at 31.4 GHz(tc31)

NSA/MWR/C1 - Spikes in air temperature readings

During this month there are occasional negative spikes in the Tkair variable. The problem 
may be corrosion in the temperature sensor or the infiltration of water from melting snow.
The dewblower was replaced and a new sensor installed

• Ambient temperature(tkair)

• Ambient temperature(tkair)

NSA/MWR/C2 - Possible bias on measurements

This instrument was refurbished at the the vendor's facility in 2008 and then sent to the 
SGP for side-by-side comparison with another MWR. During the time the instrument was at 
the SGP, it was noticed that the 23.8-GHz measurements were slightly warmer than those 
from radiometer SN10 operating at the SGP Central Facility. A comparison with radiosonde 
measurements confirmed the slight change in the measurements.

An explanation of the bias and comparison with radiosonde measurements and radiometer SN 
10 is given in the mentor's monthly data  review  for the month of April 2008.

Since there aren't radiosondes at NSA.C2, it is difficult to work around this problem. 
Based on comparison at the SGP, the bias in the 23.8-GHz channel was quantified to be ~1.5 
K. Users can attempt to subtract this amount from the 23.8-GHz measurements. 
Alternatively, use the retrieved PWV and LWV keeping in mind that there is a possible overestimation 
of PWV of ~1 mm.

On 11/16/2009 after a hardware failure of the radiometer a spare radiometer (SN15) was 
installed at the site.

• Sky brightness temperature at 23.8 GHz(tbsky23)

• 23.8 GHz sky brightness temperature derived from tip curve(tbskytip23)

NSA/MWR/C1 - Missing surface air temperature data

Some wires in the dewblower were not correctly configured.

• Ambient temperature(tkair)

• Ambient temperature(tkair)