NIM/TSI/M1 - Reprocess: Data processing problem

Due to the high aerosol conditions at Niamey, the TSI appeared to be beyond the limits of 
processing the color JPEG image into cloud fraction values. Several attempts to adjust 
the sky filter values used to process the images did not yielded the desired results. The 
processed images indicate an opaque sky cover, even in the absence of clouds.

The problem was corrected by removing the neutral density filter from the lens and 
re-adjusting the sky filter values.

The data can be reprocessed.

• PNG data stream - documentation not supported(png)

• Pixel count: number total thin(count.thin)
• Pixel count: number thin in horizon area(region.horizon.count.thin)
• Pixel count: number total opaque(count.opaque)
• Pixel count: number opaque in horizon area(region.horizon.count.opaque)
• Pixel count: number opaque in zenith circle(region.zenith.count.opaque)
• Sunshine meter(sunny)
• Pixel count: number opaque in sun circle(region.sun.count.opaque)
• Pixel count: number thin in sun circle(region.sun.count.thin)
• Percent opaque cloud(percent.opaque)
• Percentage thin cloud(percent.thin)
• Pixel count: number thin in zenith circle(region.zenith.count.thin)

NIM/MWRP/M1 - Instrument noise problem

There are spikes and elevated noise in MWRP data. The origine of the spikes is RF 
interference from various sources.  All brightness temperatures are affected, but in particular 
the 5 K-band channels. LWP retrievals are noisy and affected by spikes as a result.

• Raw data stream - documentation not supported(raw)

• Retrieved cloud liquid water content(liquidWaterContent)
• Derived relative humidity(relativeHumidity)
• Derived virtual temperature(virtualTemperature)
• Interpolated water vapor mixing ratio(waterVaporMixingRatio)
• Retrieved liquid water path using only 23.835 and 30.0 GHz(liquidWaterPath2)
• Surface air temperature for last 5 minutes of previous hour(temperature)
• Retrieved water vapor density(waterVaporDensity)
• Interpolated dewpoint temperature(dewpointTemperature)
• Retrieved liquid water path(liquidWaterPath)
• Retrieved total precipitable water vapor using only 23.835 and 30.0 GHz(totalPrecipitableWater2)
• Microwave brightness temperature(brightnessTemperature)
• Total precipitable water vapor, from microwave radiometer(totalPrecipitableWater)

• Raw data stream - documentation not supported(raw)

NIM/MWR/M1 - Instrument noise problem/RF interference

Data are affected by intermittent spikes that become more frequent starting in March 2006. 
Spikes affect data mostly around 9 AM and 18:00 PM. The origin of the spikes is probably 
RF interference.

• Mean total liquid water amount along LOS path(liq)
• Mean 23.8 GHz sky brightness temperature(tbsky23)
• Mean total water vapor amount along LOS path(vap)
• 31.4 GHz sky signal(sky31)
• Mean 31.4 GHz sky brightness temperature(tbsky31)
• 23.8 GHz sky signal(sky23)

• Raw data stream - documentation not supported(Raw data stream - documentation not supported)

• 31.4 GHz sky signal(tipsky31)
• 31.4 GHz sky brightness temperature derived from tip curve(tbsky31tip)
• 23.8 GHz sky brightness temperature derived from tip curve(tbsky23tip)
• Total water vapor along zenith path using tip-derived brightness temperatures(vaptip)
• 23.8 GHz sky signal(tipsky23)
• Total liquid water along zenith path using tip-derived brightness temperatures(liqtip)

NIM/MWRP/M1 - 51.25 GHz channel calibration drifted

After a power outage on May 5 the 51.25 GHz had a slight change in the calibration. The 
resulting LWP computed by using all 6 channels increased of about 0.025 mm (25 g/m2).

• Microwave brightness temperature(brightnessTemperature)

NIM/MWR/M1 - Reprocessed: Recalibration to correct for occasional overheating.

The radiometer was intermittently thermally unstable resulting in poor calibrations for 
four brief time periods.  These data have been reprocessed to apply corrected calibrations. 
 The affected time periods were:

20060302-20060303
20060423-20060425
20060512-20060515
20060531-20060603

• 23.8 GHz blackbody+noise injection signal(bbn23)
• Noise injection temp at 31.4 GHz adjusted to tkbb(tnd31)
• Mixer kinetic (physical) temperature(tkxc)
• Mean total water vapor amount along LOS path(vap)
• Temperature correction coefficient at 23.8 GHz(tc23)
• 23.8 GHz Blackbody signal(bb23)
• Noise diode mount temperature(tknd)
• Noise injection temp at nominal temperature at 23.8 GHz(tnd_nom23)
• Noise injection temp at nominal temperature at 31.4 GHz(tnd_nom31)
• Mean 31.4 GHz sky brightness temperature(tbsky31)
• Blackbody kinetic temperature(tkbb)
• 23.8 GHz sky signal(sky23)
• Mean total liquid water amount along LOS path(liq)
• Mean 23.8 GHz sky brightness temperature(tbsky23)
• Temperature correction coefficient at 31.4 GHz(tc31)
• 31.4 GHz blackbody+noise injection signal(bbn31)
• 31.4 GHz sky signal(sky31)
• Noise injection temp at 23.8 GHz adjusted to tkbb(tnd23)
• 31.4 GHz Blackbody signal(bb31)

• 31.4 GHz blackbody+noise injection signal(bbn31)
• Mixer kinetic (physical) temperature(tkxc)
• Noise injection temp at 31.4 GHz adjusted to tkbb(tnd31)
• 31.4 GHz Blackbody signal(bb31)
• Noise injection temp at 23.8 GHz adjusted to tkbb(tnd23)
• 31.4 GHz goodness-of-fit coefficient(r31)
• 31.4 GHz sky signal(tipsky31)
• 31.4 GHz sky brightness temperature derived from tip curve(tbsky31tip)
• 23.8 GHz goodness-of-fit coefficient(r23)
• 23.8 GHz blackbody+noise injection signal(bbn23)
• Total water vapor along zenith path using tip-derived brightness temperatures(vaptip)
• Noise injection temp at nominal temperature at 31.4 GHz(tnd_nom31)
• Temperature correction coefficient at 31.4 GHz(tc31)
• Noise injection temp at nominal temperature at 23.8 GHz(tnd_nom23)
• 23.8 GHz Blackbody signal(bb23)
• 23.8 GHz sky brightness temperature derived from tip curve(tbsky23tip)
• 23.8 GHz sky signal(tipsky23)
• Total liquid water along zenith path using tip-derived brightness temperatures(liqtip)
• Temperature correction coefficient at 23.8 GHz(tc23)
• Blackbody kinetic temperature(tkbb)
• Noise diode mount temperature(tknd)

NIM/SKYRAD/M1 - Unknown problem with PIR1

Spikes in Shaded 1 occur frequently during this time period, resulting in differences b/t 
shaded1 and shaded2 exceeding 20W/m2.  Instrument connections were checked and a spare 
PIR instrument was tried in the place of PIR1 (shaded1).  After returning the original PIR1 
to its original location data again looked good and very close to PIR2.  Problem appears 
resolved but exact cure is unknown.

• Instantaneous Downwelling Pyrgeometer Dome Thermistor Resistance, Shaded
  Pyrgeometer2(inst_down_long_shaded2_dome_resist)
• Instantaneous Downwelling Pyrgeometer Thermopile, Shaded Pyrgeometer1(inst_down_long_hemisp_shaded1_tp)
• Instantaneous Downwelling Pyrgeometer Dome Thermistor Resistance, Shaded
  Pyrgeometer1(inst_down_long_shaded1_dome_resist)
• Instantaneous Downwelling Pyrgeometer Thermopile, Shaded Pyrgeometer2(inst_down_long_hemisp_shaded2_tp)
• Instantaneous Downwelling Pyrgeometer Case Thermistor Resistance, Shaded
  Pyrgeometer1(inst_down_long_shaded1_case_resist)
• Instantaneous Downwelling Pyrgeometer Case Thermistor Resistance, Shaded
  Pyrgeometer2(inst_down_long_shaded2_case_resist)

• Downwelling Longwave Hemispheric Irradiance, Shaded Pyrgeometer1(down_long_hemisp_shaded1)
• Downwelling Longwave Hemispheric Irradiance, Shaded Pyrgeometer2, Maxima(down_long_hemisp_shaded2_max)
• Downwelling Longwave Hemispheric Irradiance, Shaded Pyrgeometer1, Minima(down_long_hemisp_shaded1_min)
• Instantaneous Downwelling Pyrgeometer Thermopile, Shaded Pyrgeometer2(inst_down_long_hemisp_shaded2_tp)
• Downwelling Longwave Hemispheric Irradiance, Shaded Pyrgeometer2, Standard
  Deviation(down_long_hemisp_shaded2_std)
• Downwelling Longwave Hemispheric Irradiance, Shaded Pyrgeometer1, Standard
  Deviation(down_long_hemisp_shaded1_std)
• Downwelling Longwave Hemispheric Irradiance, Shaded Pyrgeometer1, Maxima(down_long_hemisp_shaded1_max)
• Instantaneous Downwelling Pyrgeometer Dome Thermistor Temperature, Shaded
  Pyrgeometer2(inst_down_long_shaded2_dome_temp)
• Downwelling Longwave Hemispheric Irradiance, Shaded Pyrgeometer2, Minima(down_long_hemisp_shaded2_min)
• Downwelling Longwave Hemispheric Irradiance, Shaded Pyrgeometer2(down_long_hemisp_shaded2)
• Instantaneous Downwelling Pyrgeometer Dome Thermistor Temperature, Shaded
  Pyrgeometer1(inst_down_long_shaded1_dome_temp)
• Instantaneous Downwelling Pyrgeometer Thermopile, Shaded Pyrgeometer1(inst_down_long_hemisp_shaded1_tp)
• Instantaneous Downwelling Pyrgeometer Case Thermistor Temperature, Shaded
  Pyrgeometer2(inst_down_long_shaded2_case_temp)
• Instantaneous Downwelling Pyrgeometer Case Thermistor Temperature, Shaded
  Pyrgeometer1(inst_down_long_shaded1_case_temp)

• Raw data stream - documentation not supported(Raw data stream - documentation not supported)

NIM/TSI/M1 - Shadowband Misalignment

From installation, the shadowband was positioned south at solar noon until the vernal 
equinox when it began to migrate counter-clockwise until reaching east 37 days later on 4/26 
(about 9 days before mid-spring). The shadowband at solar noon continued to migrate until 
reaching its most northerly position (~15 deg) on the summer solstice (if everything was 
perfectly aligned, it probably would have been pointed north on this day). It then began 
to migrate clockwise and reached east again 56 days later on 8/16 (about 14 days after 
mid-summer). As expected, the shadowband reached its most southerly position on the 
autumnal equinox but was about 10 deg off of being due south. 

With the apparent alignment problem, I don't understand why the shadowband was mostly 
blocking the sun. When I started noticing this offset in May, I chose to leave it alone 
because I felt that adjusting the shadowband to where I thought it should be would cause it to 
not block the sun at either sunrise or sunset. 

The alignment was corrected on 9/29 (6 days after the day of the autumnal equinox).

• JPG data stream - documentation not supported(JPEG data stream - documentation not yet available)

• PNG data stream - documentation not supported(png)

• (MPEG data stream - documentation not yet available)

NIM/TSI/M1 - Shadowband glare

When the neutral density filter was removed from the lens, the reflection of the sun from 
the smooth shadowband strip became much brighter causing a glare in the image on clear 
days. To minimize this reflection, a rough surface (the "fuzzy" side of an adhesive velco 
strip) was placed along the length of the shadowband.

• Relative \'strength\' of direct sun(sun.strength)
• Pixel count: number total in sun circle(region.sun.count)
• Sunshine meter(sunny)

NIM/RWP/M1 - Reprocess: Wind direction offset

A strong wind storm on June 17, 2006 toppled the RWP antenna.  After repair and 
reinstallation, the wind direction reported by the instrument was rotated counterclockwise 90 
degrees, possibly because the antenna was installed rotated by 90 deg.  This condition 
continued through the remainder of deployment.

All wind direction values need to be increased by 90 degrees.

• model meridional wind velocity(v_wind)
• model zonal wind velocity(u_wind)