TWP/VCEIL/C1 - Ceilometer clock drift

During this period the ceilometer was using a software version that
provided time stamps that were based on the ceilometer clock and
not the computer clock that was continually sychronized with GPS.
This lead to times that were erroneous by as much as 2 minutes. For
most applications 2 minutes is an acceptable error, but for some
applications this may be a problem.

• Flag indicating aeri retrieval status(status_flag)
• Warning and alarm status bits(status_string)
• lat(lat)
• range(range)
• Degrees from vertical (0 to +90)(tilt_angle)
• lon(lon)
• Time offset of tweaks from base_time(time_offset)
• Dummy altitude for Zeb(alt)
• Lowest cloud base height detected.(first_cbh)
• Percentage of nominal factory setting (0 to 999%)(receiver_sensitivity)
• Third cloud base height(third_cbh)
• Laser temperature(laser_temperature)
• Backscatter sum(sum_backscatter)
• Millivolts at internal ADC input(window_contamination)
• Aerosol backscatter coefficient at 355 nm(backscatter)
• Vertical visibility(vertical_visibility)
• base time(base_time)
• Percentage of nominal factory setting (0 to 999%)(laser_pulse_energy)
• GPS raw data filename(filename)
• Detection status. See details(detection_status)
• Altitude of highest signal(alt_highest_signal)
• 6 character string describing instrument measurement parameters(measurement_parameters)
• Millivolts at internal ADC input (0 to 2500)(background_light)
• Second lowest cloud base height(second_cbh)

• null(Raw data stream - documentation not supported)

• lat(lat)
• Aerosol backscatter coefficient at 355 nm(backscatter)
• Laser temperature(laser_temperature)
• Second lowest cloud base height(second_cbh)
• Lowest cloud base height detected.(first_cbh)
• GPS raw data filename(filename)
• Backscatter sum(sum_backscatter)
• Millivolts at internal ADC input(window_contamination)
• range(range)
• Time offset of tweaks from base_time(time_offset)
• Percentage of nominal factory setting (0 to 999%)(receiver_sensitivity)
• Dummy altitude for Zeb(alt)
• Detection status. See details(detection_status)
• Percentage of nominal factory setting (0 to 999%)(laser_pulse_energy)
• Vertical visibility(vertical_visibility)
• Degrees from vertical (0 to +90)(tilt_angle)
• base time(base_time)
• 6 character string describing instrument measurement parameters(measurement_parameters)
• Altitude of highest signal(alt_highest_signal)
• Millivolts at internal ADC input (0 to 2500)(background_light)
• Warning and alarm status bits(status_string)
• Flag indicating aeri retrieval status(status_flag)
• Third cloud base height(third_cbh)
• lon(lon)

TWP/VCEIL/C1 - Extended data gap

There is no ceilometer data for this period.

• Third cloud base height(third_cbh)
• Laser temperature(laser_temperature)
• Flag indicating aeri retrieval status(status_flag)
• Millivolts at internal ADC input(window_contamination)
• Backscatter sum(sum_backscatter)
• Aerosol backscatter coefficient at 355 nm(backscatter)
• Vertical visibility(vertical_visibility)
• Warning and alarm status bits(status_string)
• lat(lat)
• base time(base_time)
• Percentage of nominal factory setting (0 to 999%)(laser_pulse_energy)
• range(range)
• GPS raw data filename(filename)
• Degrees from vertical (0 to +90)(tilt_angle)
• Detection status. See details(detection_status)
• Altitude of highest signal(alt_highest_signal)
• lon(lon)
• Time offset of tweaks from base_time(time_offset)
• Lowest cloud base height detected.(first_cbh)
• Dummy altitude for Zeb(alt)
• 6 character string describing instrument measurement parameters(measurement_parameters)
• Millivolts at internal ADC input (0 to 2500)(background_light)
• Percentage of nominal factory setting (0 to 999%)(receiver_sensitivity)
• Second lowest cloud base height(second_cbh)

• lat(lat)
• Vertical visibility(vertical_visibility)
• Aerosol backscatter coefficient at 355 nm(backscatter)
• Laser temperature(laser_temperature)
• Degrees from vertical (0 to +90)(tilt_angle)
• base time(base_time)
• Second lowest cloud base height(second_cbh)
• 6 character string describing instrument measurement parameters(measurement_parameters)
• Lowest cloud base height detected.(first_cbh)
• Millivolts at internal ADC input(window_contamination)
• Backscatter sum(sum_backscatter)
• GPS raw data filename(filename)
• Altitude of highest signal(alt_highest_signal)
• Millivolts at internal ADC input (0 to 2500)(background_light)
• Warning and alarm status bits(status_string)
• range(range)
• Time offset of tweaks from base_time(time_offset)
• Third cloud base height(third_cbh)
• Flag indicating aeri retrieval status(status_flag)
• Percentage of nominal factory setting (0 to 999%)(receiver_sensitivity)
• Dummy altitude for Zeb(alt)
• Detection status. See details(detection_status)
• lon(lon)
• Percentage of nominal factory setting (0 to 999%)(laser_pulse_energy)

TWP/VCEIL/C1 - Degraded Ceilometer Window

Data from the ceilometer during this period is suspect. From 10/28
until about 2/4 the instrument had a deteriorated window.  This
caused the ceilometer to only be able to see cloud heights up to
about 2 km.

• Third cloud base height(third_cbh)
• Aerosol backscatter coefficient at 355 nm(backscatter)
• Lowest cloud base height detected.(first_cbh)
• Second lowest cloud base height(second_cbh)

• Third cloud base height(third_cbh)
• Lowest cloud base height detected.(first_cbh)
• Aerosol backscatter coefficient at 355 nm(backscatter)
• Second lowest cloud base height(second_cbh)

TWP/C1 - Incorrect elevation reported in Manus Data

Bill Clements reports 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)