NSA/METTWR/C2 - Chilled Mirror grounding and timing issues

From beginning of data stream, the chilled mirror data was intermittent at best.  Problems 
with grounding and timing issues between logging instruments caused data to be incorrect 
and at times missing.

• VPCMH
• CMHDP
• SatVPCMH
• CMHRH
• CMHTemp

NSA/METTWR/C2 - Data Incorrect during Maintenance

The 10m tower was lowered for 2-year change-out of the met sensors.  Data during this time 
is not representative.

• RefTemp_AVG
• RH2m_STD
• DP5m_STD
• Wind speed, vector-averaged(WinSpeed_U_WVT)
• Relative humidity, average, at 2-m height(RH5m_AVG)
• QLIVolt_AVG
• VP5m_STD
• WinDir_SDU_WVT
• Temperature, air, average, at 2-m height(T2m_AVG)
• T2m_STD
• Wind speed, mean(WinSpeed_S_WVT)
• Temperature, dew point, average, at 5-m height(DP5m_AVG)
• VP2m_STD
• T5m_STD
• Pressure, vapor, at 2-m height(VP2m_AVG)
• RH5m_STD
• SatVPCMH
• Relative humidity, average, at 2-m height(RH2m_AVG)
• Pressure, vapor, at 5-m height(VP5m_AVG)
• DP2m_STD
• Temperature, dew point, average, at 2-m height(DP2m_AVG)
• Wind direction, vector-averaged(WinDir_DU_WVT)
• Temperature, air, average, at 5-m height(T5m_AVG)

NSA/METTWR/C2 -  All Data Missing or Incorrect during Maintenance

All data incorrect or missing due to change of the Serial Data multiplexer and the Vaisala 
QLI data collector during these times.

• RH2m_STD
• RefTemp_AVG
• Relative humidity, average, at 2-m height(RH5m_AVG)
• QLIVolt_AVG
• VP5m_STD
• PWcod15mi
• Precipitation Rate(PCPRate)
• CMHTemp
• T5m_STD
• VPCMH
• CMHDP
• Pressure, vapor, at 5-m height(VP5m_AVG)
• DP2m_STD
• Temperature, dew point, average, at 2-m height(DP2m_AVG)
• Wind direction, vector-averaged(WinDir_DU_WVT)
• PWCod1hr
• batt_volt
• CumSnow
• Wind speed, vector-averaged(WinSpeed_U_WVT)
• DP5m_STD
• CumH2O
• WinDir_SDU_WVT
• CMHRH
• Temperature, air, average, at 2-m height(T2m_AVG)
• T2m_STD
• Wind speed, mean(WinSpeed_S_WVT)
• Temperature, dew point, average, at 5-m height(DP5m_AVG)
• VP2m_STD
• Pressure, atmospheric(AtmPress)
• Pressure, vapor, at 2-m height(VP2m_AVG)
• PWSAlarm
• RH5m_STD
• SatVPCMH
• InstPWCod
• Relative humidity, average, at 2-m height(RH2m_AVG)
• Visibility, 1 minute average(AvgVis1mi)
• Temperature, air, average, at 5-m height(T5m_AVG)
• Visibility, 10 minute average(AvgVis10m)

NSA/METTWR/C2 - PWS Data Suspect

Data from the PWS is suspect during these times due to problems when the system was 
re-calibrated.  System was corrected.

• PWCod1hr
• CumSnow
• PWSAlarm
• CumH2O
• PWcod15mi
• InstPWCod
• Visibility, 1 minute average(AvgVis1mi)
• Precipitation Rate(PCPRate)
• Visibility, 10 minute average(AvgVis10m)

NSA/METTWR/C2 - Instrument problem

CMH and PWS stopped reporting.  Communication cable found to be broken.

• PWCod1hr
• CumSnow
• CumH2O
• PWcod15mi
• CMHRH
• Precipitation Rate(PCPRate)
• CMHTemp
• VPCMH
• CMHDP
• PWSAlarm
• SatVPCMH
• InstPWCod
• Visibility, 1 minute average(AvgVis1mi)
• Visibility, 10 minute average(AvgVis10m)

NSA/METTWR/C2 - Tower Lowered

The tower was lowered to install the GroundMFR.  Data from the T/RH probes and the wind 
speed and direction sensors are not representative during the time period.

• RH2m_STD
• Wind speed, vector-averaged(WinSpeed_U_WVT)
• DP5m_STD
• Relative humidity, average, at 2-m height(RH5m_AVG)
• WinDir_SDU_WVT
• VP5m_STD
• Temperature, air, average, at 2-m height(T2m_AVG)
• T2m_STD
• Wind speed, mean(WinSpeed_S_WVT)
• Temperature, dew point, average, at 5-m height(DP5m_AVG)
• VP2m_STD
• T5m_STD
• Pressure, vapor, at 2-m height(VP2m_AVG)
• RH5m_STD
• Relative humidity, average, at 2-m height(RH2m_AVG)
• Pressure, vapor, at 5-m height(VP5m_AVG)
• DP2m_STD
• Temperature, dew point, average, at 2-m height(DP2m_AVG)
• Wind direction, vector-averaged(WinDir_DU_WVT)
• Temperature, air, average, at 5-m height(T5m_AVG)

NSA/METTWR/C2 - Incorrect Maximum for Precip Values

The max values for cumulative rain sum of 99 mm and the rain rate of 999 mm/hr are 
incorrect.  In communication with the manufacturer it has been found that the manual was in 
error.  The actual max values of the cumulative rain sum is 99.99 mm and the rain rate is 
999.99 mm/hr.

• CumH2O
• Precipitation Rate(PCPRate)

NSA/METTWR/C2 - CMH Data Missing During Calibration

The CMH was removed for it's bi-annual cleaning and calibration.

• VPCMH
• CMHDP
• SatVPCMH
• CMHRH
• CMHTemp

NSA/METTWR/C2 - Tower Lowered, Data Not Representative

The tower was lowered to remove equipment.  The data from the wind sensors and T/RH probes 
were not representative.

• RH2m_STD
• Wind speed, vector-averaged(WinSpeed_U_WVT)
• DP5m_STD
• Relative humidity, average, at 2-m height(RH5m_AVG)
• WinDir_SDU_WVT
• VP5m_STD
• Temperature, air, average, at 2-m height(T2m_AVG)
• T2m_STD
• Wind speed, mean(WinSpeed_S_WVT)
• Temperature, dew point, average, at 5-m height(DP5m_AVG)
• VP2m_STD
• T5m_STD
• Pressure, vapor, at 2-m height(VP2m_AVG)
• RH5m_STD
• Relative humidity, average, at 2-m height(RH2m_AVG)
• Pressure, vapor, at 5-m height(VP5m_AVG)
• DP2m_STD
• Temperature, dew point, average, at 2-m height(DP2m_AVG)
• Wind direction, vector-averaged(WinDir_DU_WVT)
• Temperature, air, average, at 5-m height(T5m_AVG)

NSA/METTWR/C2 - Wind speed values artificially low

Wind speed values were artificially low due to snow/ice accumulation on the anemometer 
cups during blizzard conditions.  The heaters on the cups were not able to keep up with 
conditions.

• Wind speed, vector-averaged(WinSpeed_U_WVT)
• Wind speed, mean(WinSpeed_S_WVT)

NSA/METTWR/C2 - CMH Data incorrect

CMH data was incorrect due to blockage of intake by heavy, wet snow during blizzard 
conditions.

• VPCMH
• CMHDP
• SatVPCMH
• CMHRH
• CMHTemp

NSA/METTWR/C2 - PWS data incorrect

The Present Weather Sensor measurement optics were blocked by heavy, wet snow during 
blizzard conditions.

• PWCod1hr
• CumSnow
• PWSAlarm
• CumH2O
• PWcod15mi
• InstPWCod
• Visibility, 1 minute average(AvgVis1mi)
• Precipitation Rate(PCPRate)
• Visibility, 10 minute average(AvgVis10m)

NSA/METTWR/C2 - CMH Intake Fan Failure

Intake fan failing causing poor readings from the CMH.

• VPCMH
• CMHDP
• SatVPCMH
• CMHRH
• CMHTemp

NSA/METTWR/C2 - CMH Data Suspect

CMH data was suspect due to incorrect intake fan installed.  Proper spares were not on 
hand.

• VPCMH
• CMHDP
• SatVPCMH
• CMHRH
• CMHTemp

NSA/METTWR/C2 - CMH Data Suspect

CMH data was suspect due to blockage of intake by snow.

• VPCMH
• CMHDP
• SatVPCMH
• CMHRH
• CMHTemp

NSA/METTWR/C2 - Reprocess: Barometric Data Changed from hPa to kPa

Barometric pressure data was converted from hPa to kPa in order to standardize the 
measurement units among ARM sites and to conform to accepted standard units determined by the 
scientific community.

• Pressure, atmospheric(AtmPress)

NSA/METTWR/C2 - CMH data missing and/or incorrect during maintenance.

CMH measured data was missing and the derived variables were incorrect due to routine 
maintenance.

• VPCMH
• CMHDP
• SatVPCMH
• CMHRH
• CMHTemp

NSA/METTWR/C2 - PWS data missing/incorrect due to maintenance.

Present Weather Sensor data was missing or incorrect due to maintenance activities 
repeated approximately daily as we were trying to correct another problem.

• PWCod1hr
• CumSnow
• PWSAlarm
• CumH2O
• PWcod15mi
• InstPWCod
• Visibility, 1 minute average(AvgVis1mi)
• Precipitation Rate(PCPRate)
• CMHTemp
• Visibility, 10 minute average(AvgVis10m)

NSA/METTWR/C2 - Met data incorrect due to tower being lowered for maintenance.

Data from the tower is not representative of local conditions due to the tower being 
lowered for radiometer change.  Sensors not attached to the tower such as the Present Weather 
Sensor, the Chilled Mirror Hygrometer and the Barometer were not affected.

• RH2m_STD
• Wind speed, vector-averaged(WinSpeed_U_WVT)
• DP5m_STD
• Relative humidity, average, at 2-m height(RH5m_AVG)
• WinDir_SDU_WVT
• VP5m_STD
• Temperature, air, average, at 2-m height(T2m_AVG)
• T2m_STD
• Wind speed, mean(WinSpeed_S_WVT)
• Temperature, dew point, average, at 5-m height(DP5m_AVG)
• VP2m_STD
• T5m_STD
• Pressure, vapor, at 2-m height(VP2m_AVG)
• RH5m_STD
• Relative humidity, average, at 2-m height(RH2m_AVG)
• Pressure, vapor, at 5-m height(VP5m_AVG)
• DP2m_STD
• Temperature, dew point, average, at 2-m height(DP2m_AVG)
• Wind direction, vector-averaged(WinDir_DU_WVT)
• Temperature, air, average, at 5-m height(T5m_AVG)

NSA/METTWR/C2 - 2m Temp/RH sensor blocked with snow

The 2m RH, Dew Point and Vapor Pressure values are incorrect due to the intake of the 
aspirated shield being blocked with snow and ice.  The RH% values are artificially larger 
than the 5m and Chilled Mirror values.

• RH2m_STD
• Pressure, vapor, at 2-m height(VP2m_AVG)
• Relative humidity, average, at 2-m height(RH2m_AVG)
• DP2m_STD
• Temperature, dew point, average, at 2-m height(DP2m_AVG)
• VP2m_STD