PYE/SKYRAD/M1 - Reprocessed: Installation problems

The installation of the SKYRAD instrument was not without problems.  During all or part of 
the time period specified the calibrations were incorrect or incomplete, the downwelling 
diffuse and direct normal leads were switched, and the shadowband was severely out of 
alignment.

These data have been reprocessed to apply corrections as follows:

1) NIP & PSP-diffuse leads swapped 20050214-20050412.1645
     - swapped the NIP and PSP columns in the raw data files
     - backed out the original, incorrect calibrations 
     - applied correct calibrations
2) PSP-diffuse calibration error 050214-050215
     - backed out the original, incorrect calibration
     - applied correct calibrations
3) PSP-DS cal error 050214-050215
     - backed out the original, incorrect calibration
     - applied correct calibration
4) NIP cal error 050214-050215 and 050218-050401
     - backed out the original, incorrect calibrations
     - applied correct calibration

The reprocessed data were archived in February, 2007.

Users are encouraged to still use these data with caution only after a thorough quality 
review to be certain the data meet their requirements.

• Downwelling Shortwave Diffuse Hemisp. Irrad., Ventilated Pyranometer, Minima(down_short_diffuse_hemisp_min)
• Downwelling Shortwave Diffuse Hemisp. Irrad., Ventilated Pyranometer, Maxima(down_short_diffuse_hemisp_max)
• Irradiance, longwave, downwelling, hemispheric, shaded pyrgeometer2(down_long_hemisp_shaded2)
• inst_down_long_shaded1_case_temp
• Irradiance, longwave, downwelling, hemispheric, shaded pyrgeometer1(down_long_hemisp_shaded1)
• down_long_hemisp_shaded2_min
• inst_down_long_shaded2_dome_temp
• Temperature, Sky Infra-Red(sky_ir_temp)
• Irradiance, longwave, downwelling, hemispheric, thermopile (Shaded Pyrgeometer1)(inst_down_long_hemisp_shaded1_tp)
• Downwelling Shortwave Hemispheric Irradiance, Ventilated Pyranometer, Minima(down_short_hemisp_min)
• Irradiance, longwave, downwelling, hemispheric, thermopile (Shaded Pyrgeometer2)(inst_down_long_hemisp_shaded2_tp)
• sky_ir_temp_max
• short_direct_normal_std
• down_long_hemisp_shaded1_min
• down_long_hemisp_shaded1_std
• sky_ir_temp_std
• sky_ir_temp_min
• inst_down_long_shaded2_case_temp
• down_long_hemisp_shaded2_max
• down_short_diffuse_hemisp_std
• Radiation, shortwave, downwelling diffuse hemispheric irradiance, 1-min avg(down_short_diffuse_hemisp)
• down_long_hemisp_shaded2_std
• Radiation, shortwave, downwelling total hemispheric irradiance, 1-min avg(down_short_hemisp)
• inst_down_long_shaded1_dome_temp
• down_short_hemisp_std
• Downwelling Shortwave Hemispheric Irradiance, Ventilated Pyranometer, Maxima(down_short_hemisp_max)
• Radiation, shortwave, direct normal irradiance, 1-min avg(short_direct_normal)
• down_long_hemisp_shaded1_max
• Shortwave Direct Normal Irradiance, Pyrheliometer, Minima(short_direct_normal_min)
• Shortwave Direct Normal Irradiance, Pyrheliometer, Maxima(short_direct_normal_max)

• inst_down_long_shaded1_dome_resist
• inst_diffuse
• inst_sky_ir_signal
• Irradiance, longwave, downwelling, hemispheric, thermopile (Shaded Pyrgeometer2)(inst_down_long_hemisp_shaded2_tp)
• inst_direct_normal
• inst_down_long_shaded2_dome_resist
• inst_down_long_shaded1_case_resist
• Irradiance, longwave, downwelling, hemispheric, thermopile (Shaded Pyrgeometer1)(inst_down_long_hemisp_shaded1_tp)
• inst_global
• inst_down_long_shaded2_case_resist

PYE/TSI/M1 - Misalignment

The TSI was not aligned with true north.

• region.zenith.count
• region.horizon.count.thin
• Cloud amount, opaque (percent)(percent.opaque)
• region.horizon.count.opaque
• region.zenith.count.thin
• region.sun.count.thin
• count.unknown
• Cloud amount, thin (percent)(percent.thin)
• region.horizon.count
• count.sky
• count.thin
• count.sub.horz
• region.sun.count
• region.sun.count.opaque
• count.opaque
• count.box
• region.zenith.count.opaque
• count.mask
• count.sub.proczen

• JPEG data stream - documentation not yet available

• MPEG data stream - documentation not yet available

• Cloud decision images, Total Sky Imager, PNG format(png)

PYE/SKYRAD/M1 - Reprocessed: IRT configuration and calibration

The configuration of the IRT was inadvertently set to default and the program of the data 
loggers were changed to that used at TWP.C3.  This caused the calibration of the data to 
be wrong. It was corrected by reconfiguring the IRT and changing the conversion factors 
in the data logger program.

These data have been reprocessed to apply correct calibrations and the reprocessed data 
were archived in February, 2007.

• sky_ir_temp_std
• sky_ir_temp_min
• sky_ir_temp_max
• Temperature, Sky Infra-Red(sky_ir_temp)

• Raw data stream - documentation not supported

• inst_sky_ir_signal

PYE/MET/M1 - Data questionable

During the listed time period, the AMF was in the beginning phase of deployment.  Data 
during this time may not be representative and should be used with caution.

• Vapor pressure mean(vappress_mean)
• up_wind_dir_sd
• Wind speed, lower, 1-min avg(lo_wind_spd_arith_avg)
• precip_sd
• relh_sd
• Wind speed, lower, 1-min minimum(lo_wind_spd_min)
• Relative humidity mean(relh_mean)
• Precipitation maximum(precip_max)
• lo_wind_spd_sd
• up_wind_spd_sd
• Precipitation mean(precip_mean)
• Wind speed, lower, 1-min vector avg(lo_wind_spd_vec_avg)
• Wind direction, vector, lower, 1-min avg(lo_wind_dir_vec_avg)
• temp_sd
• Wind speed, upper, 1-min vector avg(up_wind_spd_vec_avg)
• Atmospheric pressure(atmos_pressure)
• Wind speed, upper, 1-min avg(up_wind_spd_arith_avg)
• Precipitation minimum(precip_min)
• alt
• Wind speed, lower, 1-min maximum(lo_wind_spd_max)
• internal_voltage
• Wind direction, vector, upper, 1-min avg(up_wind_dir_vec_avg)
• Wind speed, upper, 1-min maximum(up_wind_spd_max)
• Temperature mean(temp_mean)
• lo_wind_dir_sd
• logger_temp
• vappress_sd
• Wind speed, upper, 1-min minimum(up_wind_spd_min)

PYE/TSI/M1 - water in lens

The lower half of the TSI images were blurry due to water in the camera lens and/or 
filter. The problem was corrected when both were cleaned.

• sun.strength
• region.zenith.count
• region.horizon.count.thin
• Cloud amount, opaque (percent)(percent.opaque)
• region.horizon.count.opaque
• region.zenith.count.thin
• region.sun.count.thin
• count.unknown
• Cloud amount, thin (percent)(percent.thin)
• region.horizon.count
• count.sky
• count.thin
• count.sub.horz
• region.sun.count
• region.sun.count.opaque
• count.opaque
• count.box
• region.zenith.count.opaque
• count.mask
• count.sub.proczen

• JPEG data stream - documentation not yet available

• MPEG data stream - documentation not yet available

• Cloud decision images, Total Sky Imager, PNG format(png)

• C-Band Polarimetric Radar Data for Darwin, from BOM (RAW)(raw)

PYE/SONDE/M1 - Broken RH sensor

One of the RH sensors on this radiosonde was bad.  The RH oscillates rapidly between near 
0 and ambient up to approximately 11 km.  The near-zero values are incorrect.

• Humidity, relative(rh)
• Dewpoint Temperature(dp)

PYE/SONDE/M1 - Bad temperature and RH

The temperature appears to be approximately 10 degC too high during the entire sounding.  
This also causes the RH to be too low.  Most likely the problem was a bad temperature 
sensor.

• Humidity, relative(rh)
• Dry Bulb Temperature(tdry)
• Dewpoint Temperature(dp)

PYE/SONDE/M1 - Bad RH sensor

The RH sensor heating circuit failed on this sounding.  RH values during the first part of 
the sounding oscillate between a reasonable value and a very low value.  It appears that 
(a) the heating was out of phase, and (b) incorrect values were being reported during 
the first 10 minutes or so of flight.

• Humidity, relative(rh)
• Dewpoint Temperature(dp)

PYE/SONDE/M1 - Bad RH sensor

Two problems here - failure of the RH sensor heating circuit and a bad RH sensor.

• Humidity, relative(rh)
• Dewpoint Temperature(dp)

PYE/SKYRAD/M1 - IRT bias

The SKYRAD IRT measured lower sky temperatures than the AERI.  This may have been due to a 
dirty mirror or lens.

• sky_ir_temp_std
• sky_ir_temp_min
• sky_ir_temp_max
• Temperature, Sky Infra-Red(sky_ir_temp)

PYE/SKYRAD/M1 - Reprocess: Longwave Calibration error

Modified pyrgeometer calibration procedures were implemented beginning in December 2003.  
These modified procedures introduced a calibration bias in the longwave data.  The 
previous procedures were re-implemented at all sites between December 2005 and February 2006 to 
restore proper calibrations.                                                             
                The data collected while the incorrect procedures were in place are 
being reprocessing to remove the calibration bias.  Note, this also affected standard 
deviation, maximum and minimum data fields.

• Irradiance, longwave, downwelling, hemispheric, shaded pyrgeometer2(down_long_hemisp_shaded2)
• Irradiance, longwave, downwelling, hemispheric, shaded pyrgeometer1(down_long_hemisp_shaded1)

PYE/SKYRAD/M1 - Datalogger program error affected downwelling longwave

The excitation delays used in measuring the PIR1 case thermistor, "Case1", and the PIR2 
dome thermistor, "Dome2", were discovered to have been incorrectly set to 0 in the Skyrad 
datalogger program when the new CR23X based Skyrad loggers were installed.  The result of 
no delay in these measurements results in an error in the measured resistance of the 
thermistors, Case1 and Dome2, and thus the calculated PIR1 and PIR2 irradiances.  The 
absolute value of the errors are inversely proportial to temperature.

At Pt Reyes, we are unable to determine if the excitation delay problem was present.  The 
first Skyrad datalogger program installed at PYE was correct but later versions modified 
and uploaded in March and April of 2005 may have had the Delay0 problem.

The problem also can not be determined from the data.  Pt. Reyes temperature fluctuations 
throughout the year are maritime and fall into a relatively narrow range in 2005 between 
2.5-20C.  The Delay0 problem introduces larger errors into PIR1 and PIR2 irradiance 
calculations as the temperature drops.  At the lowest temperature at Pt Reyes in 2005 (approx 
2.5C occurring in March) the largest PIR1 error would be -.48 W/m2 and PIR2 +.38 W/m2.  
The scale of these errors are smaller than the resolution of the instrument and are lost 
in the normal variation of the instrument readings. Cursory review of the thermistor data 
during cold periods does not show any discernable biases.  Furthermore, the data logger 
programming "error" due to the Delay0 problem is an order of magnitude less than the total 
estimated measurement uncertainty of the pyrgeometer data from any ARM installation (+/- 
5 W/sq m for 4-coeff and +/- 10 W/sq m for 2-coeff calibrations).

Due to these issues, no Delay0 corrections will be applied to PYE Skyrad data.

• inst_down_long_shaded2_case_temp
• down_long_hemisp_shaded2_max
• down_long_hemisp_shaded2_std
• inst_down_long_shaded1_dome_temp
• Irradiance, longwave, downwelling, hemispheric, shaded pyrgeometer2(down_long_hemisp_shaded2)
• Irradiance, longwave, downwelling, hemispheric, shaded pyrgeometer1(down_long_hemisp_shaded1)
• down_long_hemisp_shaded2_min
• inst_down_long_shaded1_case_temp
• inst_down_long_shaded2_dome_temp
• Irradiance, longwave, downwelling, hemispheric, thermopile (Shaded Pyrgeometer1)(inst_down_long_hemisp_shaded1_tp)
• down_long_hemisp_shaded1_max
• Irradiance, longwave, downwelling, hemispheric, thermopile (Shaded Pyrgeometer2)(inst_down_long_hemisp_shaded2_tp)
• down_long_hemisp_shaded1_min
• down_long_hemisp_shaded1_std

• inst_down_long_shaded2_dome_resist
• inst_down_long_shaded1_case_resist
• inst_down_long_shaded1_dome_resist
• Irradiance, longwave, downwelling, hemispheric, thermopile (Shaded Pyrgeometer1)(inst_down_long_hemisp_shaded1_tp)
• Irradiance, longwave, downwelling, hemispheric, thermopile (Shaded Pyrgeometer2)(inst_down_long_hemisp_shaded2_tp)
• inst_down_long_shaded2_case_resist

PYE/SMET/M1 - Reprocess: ORG Data has very small rainrate values

The ORG data is collected via analog signal and not digital.  Therefore, we
   continuously collect data even when no rain is occurring.  We also capture
   small events such as leaves, large bugs, dust, etc blowing through the
   measurement path.  Because this discrete event occurs quickly the value is
   usually captured for 1 or 2 seconds.  This value is then averaged to the
   minute producing rainrate on the order of .009 mm/hr or less.  These values
   are not indicative of rain and should be removed from the record or summing
   over long periods can bias the climate record.  We are reprocessing the data
   to remove these small values and are adjusting the collection program to
   remove them before ingest.

• precip_sd
• Precipitation mean(precip_mean)
• Precipitation minimum(precip_min)
• Precipitation maximum(precip_max)

PYE/SMET/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, upper, 1-min maximum(up_wind_spd_max)
• Wind speed, upper, 1-min vector avg(up_wind_spd_vec_avg)
• lo_wind_spd_sd
• Wind speed, lower, 1-min avg(lo_wind_spd_arith_avg)
• up_wind_spd_sd
• Wind speed, lower, 1-min vector avg(lo_wind_spd_vec_avg)
• Wind speed, lower, 1-min minimum(lo_wind_spd_min)
• Wind speed, upper, 1-min avg(up_wind_spd_arith_avg)
• Wind speed, lower, 1-min maximum(lo_wind_spd_max)
• Wind speed, upper, 1-min minimum(up_wind_spd_min)

PYE/VCEIL/M1 - Reprocess: Incorrect serial_number and sum_backscatter fields

Attribute serial_number: In most cases, this field is not representative of the actual 
serial number of the instrument because the value did not change when an instrument changed 
locations or was replaced with a spare.
   
Variable sum_backscatter: An out-of-range condition for the "sum of detected and 
normalized backscatter" was reported as 0 instead of missing (-9999). The valid range is 0 - 
0.0999 /srad.

• sum_backscatter