TWP/MPL/C2 - laser diode failure

On Nov 20, 2001, following a data gap of several hours the MPL energy monitor reading 
showed an abrupt decrease of about 60%.  The laser energy continued to decrease to a reading 
of zero by Nov 23.  Cloud detection is satisfactory through Nov 21, but is not 
satisfactory after this time until the laser diode was replaced on Jan 08, 2002.  Data between the 
dates of 2001-11-22 and 2002-01-08 inclusive is not useful.

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• Range Heights (center of radar sample volume)(Heights)
• base time in epoch(base_time)
• MPL Cloth et al. Algorithm Significance Mask(SigniMaskMplCloth)
• Time offset from base_time(time_offset)

• Cloud base height (for first cloud above height threshold)(cloud_base_height)
• Height(height)
• Laser output energy per pulse(energy_monitor)
• Instrument Temperature(instrument_temp)
• Altitude of cloud top used in retrieval(cloud_top_height)
• Number of lidar pulses summed(shots_summed)
• Relative random error in backscatter profiles(random_error)
• Background signal(background_signal)
• Laser Temperature(laser_temp)
• Repetition Rate, or Trigger Frequency of the laser(pulse_rep)
• Cloud mask(cloud_mask_2)
• Cloud mask(cloud_mask_1)
• Time offset from base_time(time_offset)
• -180.0 - +180.0(alt)
• Detector Temperature(detector_temp)
• The update time of the historical baseline used for the cloud boundary
  determination of this sample(baseline_update_time)
• North Latitude(lat)
• lon(lon)
• base time in epoch(base_time)
• Aerosol volume backscattering coefficient at 355 nm(backscatter)
• Flag indicating whether the beam was extinguished at indicated cloud top(cloud_top_attenuation_flag)

• Laser output energy per pulse(energy_monitor)
• Time offset from base_time(time_offset)
• Laser Temperature(laser_temp)
• Sum of raw backscatter counts per bin prior to ANY corrections.(total_counts)
• Amount of time the actual laser pulse lags behind the sync trigger(laser_sync_offset)
• Voltage level which operates the thermistor(voltage_10)
• Amount of time the scalar lags behind the sync trigger(scalar_sync_offset)
• Repetition Rate, or Trigger Frequency of the laser(pulse_rep)
• Voltage level which operates the energy monitor(voltage_15)
• Time in nanoseconds for each range bin of multichannel scalar card.(range_bin_time)
• Amount of time laser pulse lags behind the scalar trigger(laser_scalar_sync_offset)
• Number of lidar pulses summed(shots_summed)
• Height(height)
• Angle of orientation with respect to true geographic north(transceiver_azimuth_angle)
• value represents earliest applicable date as yyyymmdd(property)
• lon(lon)
• Number of laser pulses summed during measurement interval(shots_sum)
• base time in epoch(base_time)
• Angle of inclination with respect to horizontal(transceiver_altitude_angle)
• Detector Temperature(detector_temp)
• Distance to the center of the corresponding range bin(range)
• Preliminary cloud base height above ground level(preliminary_cbh)
• Instrument Temperature(instrument_temp)
• -180.0 - +180.0(alt)
• Repetition rate, or Trigger Frequency of the laser(trigger_freq)
• Aerosol volume backscattering coefficient at 355 nm(backscatter)
• Deadtime correction factor(deadtime_correction)
• Distance from leading edge of first range bin to the center of each bin .(range_bins)
• North Latitude(lat)
• Background signal(background_signal)
• Subtract from range_bins to yield range(range_offset)
• Maximum altitude retrieved from multichannel scalar card.(max_altitude)
• Width of range-bins calculated from range_bin_time(range_bin_width)
• Filter Temperature(filter_temp)
• time_in_seconds_since_volume_start(time)
• Voltage level which operates the A/D card and the detector(voltage_05)

• lon(lon)
• Average cloud base height used in the retrieval(cbh)
• base time in epoch(base_time)
• Time offset from base_time(time_offset)
• North Latitude(lat)
• -180.0 - +180.0(alt)

• (Raw data stream - documentation not supported)

• MPL Cloth et al. Algorithm Cloud Mask(CloudMaskMplCloth)
• Time offset from base_time(time_offset)
• Range Heights (center of radar sample volume)(Heights)
• base time in epoch(base_time)

• (Raw data stream - documentation not supported)