TWP/MET/C3 - WIND DIRECTION SENSOR #2 MISALIGNED

Wind direction sensor #2 was misaligned and off by 15 degrees.

• Wind #2 direction vector average(wind2_dir_vec_avg)
• Wind #2 direction standard deviation(wind2_dir_sd)

• Wind #2 direction standard deviation(wind2_dir_sd)
• Wind #2 direction vector average(wind2_dir_vec_avg)

TWP/SMET/C3 - Intermittent Pressure Sensor Failure

The Barometric Pressure sensor was intermittently failing at TWP site C3 Darwin.  At times 
there were large pressure fluctuations occurring on the order of 24 mb in a few minutes. 
 Times of large pressure fluctuations are readily apparent in the data.  At these times 
the data should be carefully analyzed before determining it's usefulness.  In between the 
periods of large fluctuations the readings appear to be stable.  It is still suggested 
that independent pressure data be obtained for comparison before use.

• Barometric Pressure(atmos_pressure)

• Barometric Pressure(atmos_pressure)

TWP/SMET/C3 - Data reported at 15sec rather than 60s intervals

Data in these data streams should be reports at 60sec intervals, but
the logger program running during this time had the interval set to
15s.  Users will have to average the 15sec data to get 60sec data.

• Vapor pressure mean(vappress_mean)
• External voltage(external_voltage)
• Temperature minimum(temp_min)
• Precipitation standard deviation(precip_sd)
• base time(base_time)
• Precipitation mean(precip_mean)
• Barometric Pressure(atmos_pressure)
• Wind #1 direction vector average(wind1_dir_vec_avg)
• Wind #2 speed maximum(wind2_spd_max)
• Wind #2 speed standard deviation(wind2_spd_sd)
• Wind #1 speed minimum(wind1_spd_min)
• lat(lat)
• Wind #1 speed arithmetic average(wind1_spd_arith_avg)
• Dummy altitude for Zeb(alt)
• Logger panel temperature(logger_temp)
• Std Dev of Air Temperature(temp_sd)
• Vapor pressure standard deviation(vappress_sd)
• Relative humidity maximum(relh_max)
• Mean Air Temperature or Hardware Error(temp_mean)
• lon(lon)
• Wind #1 speed maximum gust(wind1_spd_max_gust)
• Std Dev of Relative Humidity or Hardware Error Code(relh_sd)
• Mean Relative Humidity(relh_mean)
• Time offset of tweaks from base_time(time_offset)
• Relative humidity minimum(relh_min)
• Wind #2 direction standard deviation(wind2_dir_sd)
• Bit data. See details.(bit_data)
• Wind #2 direction vector average(wind2_dir_vec_avg)
• Wind #1 speed standard deviation(wind1_spd_sd)
• Wind #2 speed minimum(wind2_spd_min)
• Battery Voltage(internal_voltage)
• Wind #1 speed vector average(wind1_spd_vec_avg)
• Temperature maximum(temp_max)
• precipitation minimum(precip_min)
• Wind #2 speed arithmetic average(wind2_spd_arith_avg)
• Wind #2 speed vector average(wind2_spd_vec_avg)
• Wind #1 speed maximum(wind1_spd_max)
• Precipitation maximum(precip_max)
• Wind #1 direction standard deviation(wind1_dir_sd)
• Wind #2 speed maximum gust(wind2_spd_max_gust)

• Time offset of tweaks from base_time(time_offset)
• Precipitation maximum(precip_max)
• Battery Voltage(internal_voltage)
• Wind #1 speed minimum(wind1_spd_min)
• Wind #2 speed maximum(wind2_spd_max)
• Wind #1 direction standard deviation(wind1_dir_sd)
• Wind #2 speed minimum(wind2_spd_min)
• Wind #1 speed maximum(wind1_spd_max)
• Mean Air Temperature or Hardware Error(temp_mean)
• Temperature maximum(temp_max)
• Barometric Pressure(atmos_pressure)
• Relative humidity maximum(relh_max)
• Mean Relative Humidity(relh_mean)
• Wind #1 direction vector average(wind1_dir_vec_avg)
• Wind #1 speed standard deviation(wind1_spd_sd)
• Std Dev of Relative Humidity or Hardware Error Code(relh_sd)
• Relative humidity minimum(relh_min)
• Bit data. See details.(bit_data)
• Temperature minimum(temp_min)
• Dummy altitude for Zeb(alt)
• Wind #2 speed maximum gust(wind2_spd_max_gust)
• Precipitation standard deviation(precip_sd)
• Wind #1 speed maximum gust(wind1_spd_max_gust)
• lon(lon)
• Wind #2 direction standard deviation(wind2_dir_sd)
• Wind #2 speed standard deviation(wind2_spd_sd)
• External voltage(external_voltage)
• lat(lat)
• Wind #2 speed arithmetic average(wind2_spd_arith_avg)
• Logger panel temperature(logger_temp)
• precipitation minimum(precip_min)
• Vapor pressure mean(vappress_mean)
• Vapor pressure standard deviation(vappress_sd)
• Wind #1 speed vector average(wind1_spd_vec_avg)
• Wind #2 direction vector average(wind2_dir_vec_avg)
• Precipitation mean(precip_mean)
• Wind #2 speed vector average(wind2_spd_vec_avg)
• base time(base_time)
• Wind #1 speed arithmetic average(wind1_spd_arith_avg)
• Std Dev of Air Temperature(temp_sd)

TWP/SMET/C3 - Rain blocked pressure port

Atmospheric pressure values were suspect due to anomolous readings during heavy rain 
events.  Suspect blockage of port due to rainfall.  New logger and enclosure corrected problem.

• Barometric Pressure(atmos_pressure)

TWP/SMET/C3 - Data missing due to Logger Change

All Data from this site are missing during this time period due to a change of the 
collection system, logger and enclosure.  Data resumed after change.

• External voltage(external_voltage)
• lat(lat)
• Time offset of tweaks from base_time(time_offset)
• Precipitation maximum(precip_max)
• Wind #2 speed arithmetic average(wind2_spd_arith_avg)
• Battery Voltage(internal_voltage)
• Wind #1 speed minimum(wind1_spd_min)
• Logger panel temperature(logger_temp)
• Wind #2 speed maximum(wind2_spd_max)
• precipitation minimum(precip_min)
• Wind #1 direction standard deviation(wind1_dir_sd)
• Wind #2 speed minimum(wind2_spd_min)
• Wind #1 speed maximum(wind1_spd_max)
• Mean Air Temperature or Hardware Error(temp_mean)
• Temperature maximum(temp_max)
• Vapor pressure mean(vappress_mean)
• Barometric Pressure(atmos_pressure)
• Vapor pressure standard deviation(vappress_sd)
• Mean Relative Humidity(relh_mean)
• Relative humidity maximum(relh_max)
• Wind #1 direction vector average(wind1_dir_vec_avg)
• Wind #1 speed standard deviation(wind1_spd_sd)
• Wind #1 speed vector average(wind1_spd_vec_avg)
• Wind #2 direction vector average(wind2_dir_vec_avg)
• Std Dev of Relative Humidity or Hardware Error Code(relh_sd)
• Relative humidity minimum(relh_min)
• Bit data. See details.(bit_data)
• Precipitation mean(precip_mean)
• Wind #2 speed vector average(wind2_spd_vec_avg)
• base time(base_time)
• Temperature minimum(temp_min)
• Dummy altitude for Zeb(alt)
• Wind #2 speed maximum gust(wind2_spd_max_gust)
• Precipitation standard deviation(precip_sd)
• Wind #1 speed maximum gust(wind1_spd_max_gust)
• Wind #1 speed arithmetic average(wind1_spd_arith_avg)
• lon(lon)
• Wind #2 direction standard deviation(wind2_dir_sd)
• Wind #2 speed standard deviation(wind2_spd_sd)
• Std Dev of Air Temperature(temp_sd)

TWP/SMET/C3 - Negative rainfall rates

Due to limitations of the Zeno dataloggers all voltage measurements
from the optical rain gauge (ORG) were converted to rainfall rates. 
This resulted in negative values for rain rates.  Any value below
0.10 mm/hr should be considered to be 0 mm/hr.  New dataloggers 
alleviated this problem.

• Precipitation mean(precip_mean)
• Precipitation maximum(precip_max)
• Precipitation standard deviation(precip_sd)
• precipitation minimum(precip_min)

TWP/SMET/C3 - Data non-representative

Tower mast was lowered for inspection.  Data during this time is non-representative.

• Precipitation maximum(precip_max)
• Wind #2 speed arithmetic average(wind2_spd_arith_avg)
• Wind #1 speed minimum(wind1_spd_min)
• Wind #2 speed maximum(wind2_spd_max)
• precipitation minimum(precip_min)
• Wind #1 direction standard deviation(wind1_dir_sd)
• Mean Air Temperature or Hardware Error(temp_mean)
• Wind #1 speed maximum(wind1_spd_max)
• Wind #2 speed minimum(wind2_spd_min)
• Temperature maximum(temp_max)
• Vapor pressure mean(vappress_mean)
• Barometric Pressure(atmos_pressure)
• Vapor pressure standard deviation(vappress_sd)
• Mean Relative Humidity(relh_mean)
• Relative humidity maximum(relh_max)
• Wind #1 direction vector average(wind1_dir_vec_avg)
• Wind #1 speed standard deviation(wind1_spd_sd)
• Wind #1 speed vector average(wind1_spd_vec_avg)
• Wind #2 direction vector average(wind2_dir_vec_avg)
• Std Dev of Relative Humidity or Hardware Error Code(relh_sd)
• Relative humidity minimum(relh_min)
• Precipitation mean(precip_mean)
• Wind #2 speed vector average(wind2_spd_vec_avg)
• Temperature minimum(temp_min)
• Wind #2 speed maximum gust(wind2_spd_max_gust)
• Precipitation standard deviation(precip_sd)
• Wind #1 speed maximum gust(wind1_spd_max_gust)
• Wind #1 speed arithmetic average(wind1_spd_arith_avg)
• Wind #2 direction standard deviation(wind2_dir_sd)
• Wind #2 speed standard deviation(wind2_spd_sd)
• Std Dev of Air Temperature(temp_sd)

TWP/SMET/C3 - Instrument logger problem, Sensor failure

The wind_lower direction sensor failed on 4/14 and disagrees significantly with the 
wind_upper direction.  The wind_lower sensor reports a constant value around 0-15 degrees since 
it failed.  Testing showed that excitation channel two on the logger was the problem.  
Logger was replaced by spare.

• Wind #2 direction standard deviation(wind2_dir_sd)
• Wind #2 direction vector average(wind2_dir_vec_avg)

TWP/SMET/C3 - Data not representative

Tower was lowered for radiometer change and characterization.  Wind, temp and RH data not 
representative of local conditions.

• Wind #2 speed arithmetic average(wind2_spd_arith_avg)
• Wind #1 speed minimum(wind1_spd_min)
• Wind #2 speed maximum(wind2_spd_max)
• Wind #1 direction standard deviation(wind1_dir_sd)
• Mean Air Temperature or Hardware Error(temp_mean)
• Wind #1 speed maximum(wind1_spd_max)
• Wind #2 speed minimum(wind2_spd_min)
• Temperature maximum(temp_max)
• Vapor pressure mean(vappress_mean)
• Vapor pressure standard deviation(vappress_sd)
• Mean Relative Humidity(relh_mean)
• Relative humidity maximum(relh_max)
• Wind #1 direction vector average(wind1_dir_vec_avg)
• Wind #1 speed standard deviation(wind1_spd_sd)
• Wind #1 speed vector average(wind1_spd_vec_avg)
• Std Dev of Relative Humidity or Hardware Error Code(relh_sd)
• Wind #2 direction vector average(wind2_dir_vec_avg)
• Relative humidity minimum(relh_min)
• Wind #2 speed vector average(wind2_spd_vec_avg)
• Temperature minimum(temp_min)
• Wind #2 speed maximum gust(wind2_spd_max_gust)
• Wind #1 speed maximum gust(wind1_spd_max_gust)
• Wind #2 speed standard deviation(wind2_spd_sd)
• Wind #2 direction standard deviation(wind2_dir_sd)
• Wind #1 speed arithmetic average(wind1_spd_arith_avg)
• Std Dev of Air Temperature(temp_sd)

TWP/SMET/C3 - Towrr lowered for sensor comparisons, data not representative

The tower was lowered for radiometer change and comparisons.  During the time period the 
data listed was not representative.

• Wind #2 speed arithmetic average(wind2_spd_arith_avg)
• Wind #1 speed minimum(wind1_spd_min)
• Wind #2 speed maximum(wind2_spd_max)
• Wind #1 direction standard deviation(wind1_dir_sd)
• Mean Air Temperature or Hardware Error(temp_mean)
• Wind #1 speed maximum(wind1_spd_max)
• Wind #2 speed minimum(wind2_spd_min)
• Temperature maximum(temp_max)
• Vapor pressure mean(vappress_mean)
• Vapor pressure standard deviation(vappress_sd)
• Mean Relative Humidity(relh_mean)
• Relative humidity maximum(relh_max)
• Wind #1 direction vector average(wind1_dir_vec_avg)
• Wind #1 speed standard deviation(wind1_spd_sd)
• Wind #1 speed vector average(wind1_spd_vec_avg)
• Std Dev of Relative Humidity or Hardware Error Code(relh_sd)
• Wind #2 direction vector average(wind2_dir_vec_avg)
• Relative humidity minimum(relh_min)
• Wind #2 speed vector average(wind2_spd_vec_avg)
• Temperature minimum(temp_min)
• Wind #2 speed maximum gust(wind2_spd_max_gust)
• Wind #1 speed maximum gust(wind1_spd_max_gust)
• Wind #2 speed standard deviation(wind2_spd_sd)
• Wind #2 direction standard deviation(wind2_dir_sd)
• Wind #1 speed arithmetic average(wind1_spd_arith_avg)
• Std Dev of Air Temperature(temp_sd)

TWP/SMET/C3 - Upper wind sensor failure

A lightning strike destroyed the upper (#1) wind sensor.

• Wind #1 direction vector average(wind1_dir_vec_avg)
• Wind #1 speed minimum(wind1_spd_min)
• Wind #1 speed maximum(wind1_spd_max)
• Wind #1 speed standard deviation(wind1_spd_sd)
• Wind #1 speed maximum gust(wind1_spd_max_gust)
• Wind #1 speed arithmetic average(wind1_spd_arith_avg)
• Wind #1 speed vector average(wind1_spd_vec_avg)
• Wind #1 direction standard deviation(wind1_dir_sd)

TWP/SMET/C3 - RH Values Artificially High

Lightning strike caused RH readings to be higher than reasonable (130%).

• Vapor pressure standard deviation(vappress_sd)
• Mean Relative Humidity(relh_mean)
• Relative humidity maximum(relh_max)
• Vapor pressure mean(vappress_mean)
• Std Dev of Relative Humidity or Hardware Error Code(relh_sd)
• Relative humidity minimum(relh_min)

TWP/SMET/C3 - Instrument failure

A lightning strike caused a failure in the ORG.  Rainfall was being continually recorded.

• Precipitation mean(precip_mean)
• Precipitation maximum(precip_max)
• Precipitation standard deviation(precip_sd)
• precipitation minimum(precip_min)

TWP/SMET/C3 - ORG data noisy due to degraded ground

SMET Rain Data began to be noisy during December 2005 and the problem slowly became worse 
over time so that in February 2006 the ORG was reporting with a constant background value 
of around 0.10 mm/hr rain rate.  ORG voltage showed a near constant value above the 85mV 
threshold.  The ground for the ORG had become degraded and was lost due to corrosion.

• Precipitation mean(precip_mean)
• Precipitation maximum(precip_max)
• Precipitation standard deviation(precip_sd)
• precipitation minimum(precip_min)

TWP/SMET/C3 - Reprocess: Windspeed2 calibration error

The lower anemometer was replaced afer being removed in anticipation of cyclone Monica. 
The calibration coefficient was not changed during this period so the wind speeds are a 
little low (0.2%).

• Wind #2 speed vector average(wind2_spd_vec_avg)
• Wind #2 speed arithmetic average(wind2_spd_arith_avg)
• Wind #2 speed maximum gust(wind2_spd_max_gust)
• Wind #2 speed minimum(wind2_spd_min)
• Wind #2 speed maximum(wind2_spd_max)
• Wind #2 speed standard deviation(wind2_spd_sd)

TWP/SMET/C3 - Anemometer Readings Incorrect

The Anemometer readings were incorrect due to the tower being lowered for maintenance.

• Wind #2 speed arithmetic average(wind2_spd_arith_avg)
• Wind #1 speed minimum(wind1_spd_min)
• Wind #1 direction vector average(wind1_dir_vec_avg)
• Wind #1 speed standard deviation(wind1_spd_sd)
• Wind #2 speed maximum(wind2_spd_max)
• Wind #1 speed vector average(wind1_spd_vec_avg)
• Wind #2 direction vector average(wind2_dir_vec_avg)
• Wind #1 direction standard deviation(wind1_dir_sd)
• Wind #2 speed vector average(wind2_spd_vec_avg)
• Wind #2 speed maximum gust(wind2_spd_max_gust)
• Wind #1 speed maximum(wind1_spd_max)
• Wind #2 speed minimum(wind2_spd_min)
• Wind #1 speed maximum gust(wind1_spd_max_gust)
• Wind #1 speed arithmetic average(wind1_spd_arith_avg)
• Wind #2 direction standard deviation(wind2_dir_sd)
• Wind #2 speed standard deviation(wind2_spd_sd)

TWP/SMET/C3 - 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.

• Barometric Pressure(atmos_pressure)

TWP/SMET/C3 - Reprocess: Tipping bucket rain gauge added

A tipping bucket rain gauge was added to the SMET suite of instruments effective 20060926. 
 Two new variables (count and rain amount) were added at the end of the twpsmet60sC1.b1 
datastream.  When reprocessing of this datastream occurs these variables will be added 
with -9999 (missing) as the value for dates prior to gauge installation.

• base time(base_time)

TWP/SMET/C3 - Barometer Data Incorrect

The barometer data was incorrect or missing due to water intrusion.

• Barometric Pressure(atmos_pressure)

TWP/SMET/C3 - Data Incorrect Due to Water Intrusion

Data became erratic and unreasonable after water intrusion into the enclosure.

• Vapor pressure standard deviation(vappress_sd)
• Precipitation maximum(precip_max)
• Relative humidity maximum(relh_max)
• Mean Relative Humidity(relh_mean)
• Std Dev of Relative Humidity or Hardware Error Code(relh_sd)
• Relative humidity minimum(relh_min)
• precipitation minimum(precip_min)
• Precipitation mean(precip_mean)
• Temperature minimum(temp_min)
• Mean Air Temperature or Hardware Error(temp_mean)
• Temperature maximum(temp_max)
• Precipitation standard deviation(precip_sd)
• Vapor pressure mean(vappress_mean)
• Std Dev of Air Temperature(temp_sd)

TWP/SMET/C3 - Upper wind speed artificially slow

The upper wind measurement was consistently slower by around 0.5 - 1 m/s than the lower 
wind measurement.  The bearings on the upper wind measurement were binding.

• Wind #1 speed minimum(wind1_spd_min)
• Wind #1 speed maximum(wind1_spd_max)
• Wind #1 speed standard deviation(wind1_spd_sd)
• Wind #1 speed maximum gust(wind1_spd_max_gust)
• Wind #1 speed vector average(wind1_spd_vec_avg)

TWP/SMET/C3 - ORG overestimated rainfall

Optical rain gauge (ORG) measured approximately 10mm higher than two co-located tipping 
bucket rain gauges and a co-located disdrometer.  The ORG is typically higher but usually 
not by an order of magnitude.

• Precipitation mean(precip_mean)
• Precipitation maximum(precip_max)
• Precipitation standard deviation(precip_sd)
• precipitation minimum(precip_min)

TWP/SMET/C3 - Upper Wind Sensor Data Questionable

The wind_up vs. wind_low wind directions diverged, with the differences between the two 
eventually reached 45 degrees. The Upper sensor was found to be mis-aligned and loose.

• Wind #1 direction vector average(wind1_dir_vec_avg)
• Wind #1 speed minimum(wind1_spd_min)
• Wind #1 speed maximum(wind1_spd_max)
• Wind #1 speed standard deviation(wind1_spd_sd)
• Wind #1 speed maximum gust(wind1_spd_max_gust)
• Wind #1 speed arithmetic average(wind1_spd_arith_avg)
• Wind #1 speed vector average(wind1_spd_vec_avg)
• Wind #1 direction standard deviation(wind1_dir_sd)