TWP/SMET/C1 - Wind speed calibration errors

Wind speed calibration factors were reversed between wind speed sensors 1 (upper) and 2 
(lower). Results in less than 1% error, but correction factors may be used.

To correct wind speed #1 (upper) add 0.03 m/s.
To correct wind speed #2 (lower) subtract 0.03 m/s.

• Lower sensor, wind speed vector average(lo_spd_vec_avg)
• Upper sensor, wind speed maximum(up_spd_max)
• Upper sensor, wind speed arithmetic average(up_spd_arith_avg)
• Lower sensor, wind speed standard deviation(lo_spd_sd)
• Upper sensor, wind speed minimum(up_spd_min)
• Upper sensor, wind speed standard deviation(up_spd_sd)
• Lower sensor, wind speed arithmetic average(lo_spd_arith_avg)
• Lower sensor, wind speed minimum(lo_spd_min)
• Upper sensor, wind speed vector average(up_spd_vec_avg)
• Lower sensor, wind speed maximum(lo_spd_max)

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

TWP/SMET/C1 - Processing error results in missing data field

The bit_data variable is missing from the twpsmet60sC1.b1
data from 4/1/01-9/30/01 due to a processing error.  These
data are in the queue for reprocessing at low priority.

• Bit data. See details.(bit_data)

TWP/SMET/C1/C2 - Switch to new Data Header Formats not timely

On April 1, 2001 at 00:00:00 new data header with consistent variable naming conventions, 
etc were to be used for all sites, all data streams.  At the TWP sites the time of the 
movement to the new convention did not occur precisely at 00:00:00.  The following data 
files contain between 40 seconds and 20 minutes of data from 4/1/02 in the old format.  The 
delayed format change did not affect data quality in any way.

twpsmet60sC1.a1.20010401.000001.cdf
twpsmet60sC1.b1.20010401.000001.cdf
twpsmet60sC2.a1.20010401.000000.cdf
twpsmet60sC2.b1.20010401.000000.cdf

• Battery Voltage(internal_voltage)
• base time(base_time)
• Logger panel temperature(logger_temp)
• Tipping bucket raingauge count total(tbrg_count_total)
• Std Dev of Relative Humidity or Hardware Error Code(relh_sd)
• Lower sensor, wind speed minimum(lo_spd_min)
• Lower sensor, wind direction vector average(lo_dir_vec_avg)
• Upper sensor, wind speed arithmetic average(up_spd_arith_avg)
• precipitation minimum(precip_min)
• Precipitation maximum(precip_max)
• Dummy altitude for Zeb(alt)
• Lower sensor, wind direction standard deviation(lo_dir_sd)
• Upper sensor, wind speed minimum(up_spd_min)
• Upper sensor, wind direction standard deviation(up_dir_sd)
• Upper sensor, wind direction vector average(up_dir_vec_avg)
• Tipping bucket raingauge total(tbrg_total)
• Vapor pressure standard deviation(vappress_sd)
• Mean Relative Humidity(relh_mean)
• Mean Air Temperature or Hardware Error(temp_mean)
• Lower sensor, wind speed standard deviation(lo_spd_sd)
• Upper sensor, wind speed standard deviation(up_spd_sd)
• time(time)
• lon(lon)
• Upper sensor, wind speed vector average(up_spd_vec_avg)
• lat(lat)
• Lower sensor, wind speed maximum(lo_spd_max)
• Precipitation mean(precip_mean)
• Std Dev of Air Temperature(temp_sd)
• Lower sensor, wind speed arithmetic average(lo_spd_arith_avg)
• Time offset of tweaks from base_time(time_offset)
• Vapor pressure mean(vappress_mean)
• Precipitation standard deviation(precip_sd)
• Barometric Pressure(atmos_pressure)
• Lower sensor, wind speed vector average(lo_spd_vec_avg)
• Upper sensor, wind speed maximum(up_spd_max)

• Upper sensor, wind speed maximum(up_spd_max)
• base time(base_time)
• Lower sensor, wind speed arithmetic average(lo_spd_arith_avg)
• Lower sensor, wind speed maximum(lo_spd_max)
• precipitation minimum(precip_min)
• Battery Voltage(internal_voltage)
• Precipitation standard deviation(precip_sd)
• Upper sensor, wind speed minimum(up_spd_min)
• Upper sensor, wind direction standard deviation(up_dir_sd)
• Upper sensor, wind speed vector average(up_spd_vec_avg)
• Time offset of tweaks from base_time(time_offset)
• Tipping bucket raingauge total(tbrg_total)
• Lower sensor, wind direction vector average(lo_dir_vec_avg)
• Dummy altitude for Zeb(alt)
• Logger panel temperature(logger_temp)
• Upper sensor, wind speed standard deviation(up_spd_sd)
• Vapor pressure mean(vappress_mean)
• Lower sensor, wind speed minimum(lo_spd_min)
• Std Dev of Relative Humidity or Hardware Error Code(relh_sd)
• Barometric Pressure(atmos_pressure)
• Vapor pressure standard deviation(vappress_sd)
• lat(lat)
• time(time)
• Precipitation maximum(precip_max)
• Upper sensor, wind direction vector average(up_dir_vec_avg)
• Lower sensor, wind direction standard deviation(lo_dir_sd)
• Mean Relative Humidity(relh_mean)
• Mean Air Temperature or Hardware Error(temp_mean)
• Upper sensor, wind speed arithmetic average(up_spd_arith_avg)
• lon(lon)
• Lower sensor, wind speed standard deviation(lo_spd_sd)
• Tipping bucket raingauge count total(tbrg_count_total)
• Std Dev of Air Temperature(temp_sd)
• Lower sensor, wind speed vector average(lo_spd_vec_avg)
• Precipitation mean(precip_mean)

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

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

TWP/C1 - Incorrect elevation reported in Manus Data

(From Bill Clements) We have been using 6m MSL as the station
elevation of Momote (Manus).  This was based on information
posted near the station barometer in the Momote Weather Service
Office.  It turns out that the official WMO station elevation
for Momote is 4m MSL and the upper air elevation is 5m MSL.

All Manus instruments except the sonde station are at 4m MSL.
The sonde launching station is at 5m MSL.

• Dummy altitude for Zeb(alt)

• Dummy altitude for Zeb(alt)

• Dummy altitude for Zeb(alt)

• Dummy altitude for Zeb(alt)

• Dummy altitude for Zeb(alt)

TWP/SMET/C1 - Reprocess: Lower Wind Speed incorrect

The lower wind speed sensor (sensor #2) was reporting values 10 times above the actual 
value.  During an update to the logger configuration file the calibration multiplier was 
incorrectly entered.  The multiplier inserted was .97630 when it should have been .09763.  
This caused the readings from this sensor to be incorrect.

• Lower sensor, wind speed vector average(lo_spd_vec_avg)
• Lower sensor, wind speed arithmetic average(lo_spd_arith_avg)
• Lower sensor, wind speed minimum(lo_spd_min)
• Lower sensor, wind speed standard deviation(lo_spd_sd)
• Lower sensor, wind speed maximum(lo_spd_max)

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

TWP/SMET/C1 - 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 minimum(precip_min)
• Precipitation maximum(precip_max)
• Precipitation standard deviation(precip_sd)

TWP/SMET/C1 - 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 #1 speed maximum gust(wind1_spd_max_gust)
• Wind #2 speed minimum(wind2_spd_min)
• Wind #2 speed arithmetic average(wind2_spd_arith_avg)
• Wind #1 speed standard deviation(wind1_spd_sd)
• Wind #1 speed vector average(wind1_spd_vec_avg)
• Wind #2 speed vector average(wind2_spd_vec_avg)
• Wind #2 speed standard deviation(wind2_spd_sd)
• Wind #2 speed maximum(wind2_spd_max)
• Wind #1 speed maximum(wind1_spd_max)
• Wind #2 speed maximum gust(wind2_spd_max_gust)
• Wind #1 speed minimum(wind1_spd_min)
• Wind #1 speed arithmetic average(wind1_spd_arith_avg)