DQRID : D111004.3
Start DateStart TimeEnd DateEnd Time Data Quality Metric
09/29/2011000010/06/20111500Incorrect
07/15/2011100007/15/20111400Incorrect
05/03/2012143006/12/20121930Incorrect
08/08/2011130009/15/20110000Incorrect
more
Subject:
SGP/RL/C1 - Bad shot count data
DataStreams:sgprlprofmerge1turnC1.c0, sgp10rlprofdep1turnC1.c1, sgp10rlprofasr1ferrC1.c1,
sgp10rlprofmr1turnC1.c1, sgprlC1.a0, sgp10rlprofext1ferrC1.c1
Description:
The number of laser pulses averaged per profile, or shot count, exhibited erratic behavior 
during the periods in question. The values reported in the sgprlC1.a0 datastream were 
incorrect and varied radically from profile to profile. Shot counts are used in the Merge 
VAP to compute photon count rates, which are then used by all the other RL VAPs. Thus, the 
shot count problem renders all of the RL VAPs bad or suspect during the periods in question.
It appears that the problem was caused as the signal on the line between two triggering 
units got noisier over time, causing the second unit to occasionally trigger on noise. The 
second unit triggers the Licel electronics. So the false triggering on the second unit 
caused false shot count readings. On 6 October 2011 the trigger level was adjusted by the 
on-site technician, and this solved the problem.


On 3 May 2012 the DG535 pulse generator, which is used to trigger the Licel data 
recorders, was swapped out with a spare. After installation of the spare, the system started 
recording erroneous values of shot counts. The problem was fixed on 12 June 2012 when the 
on-site tech increased trigger level on the DG535.
Suggestions: 
There is not much one can do. The shot counts were not being reported correctly and 

they varied radially from beam to beam. All channels were affected.
Measurements:sgp10rlprofext1ferrC1.c1:
  • aod_1_max_ht
  • extinction_from_backscatter_error
  • extinction_high
  • extinction_married1
  • extinction_low_error
  • aod_bscat_error
  • extinction_low_resolution
  • Sa_1
  • Sa_2
  • aod_married1_profile
  • shots_summed
  • aod_bscat
  • extinction_high_resolution
  • aod_married1
  • aod_married1_error
  • extinction_high_error
  • extinction_from_backscatter
  • aod_1_profile
  • backscatter
  • extinction_married1_mask
  • extinction_1_error
  • extinction_1_resolution
  • aod_bscat_profile
  • aod_1_error
  • smoothed_backscatter
  • aod_bscat_max_ht
  • extinction_low
  • extinction_married1_error
  • backscatter_error
  • smoothed_backscatter_error
  • tweaks
  • aod_married1_max_ht
  • extinction_1
  • aod_1
  • extinction_high_olap_corrected_error
  • extinction_high_olap_corrected
more
sgprlprofmerge1turnC1.c0:
  • elastic_counts_high_glue_coef_slope
  • nitrogen_counts_high_glue_coef_offset
  • parameters_nitrogen_low
  • nitrogen_counts_low_glue_coef_offset
  • cbh
  • water_counts_low_glue_coef_slope
  • elastic_counts_high
  • electronic_background_water_analog_high
  • electronic_background_water_analog_low
  • water_counts_low_glue_coef_offset
  • liquid_counts_high
  • parameters_nitrogen_high
  • solar_offset_nudge_lw
  • water_counts_high_glue_coef_offset
  • electronic_background_t1_analog_high
  • electronic_background_t2_analog_high
  • solar_offset_nudge_nh
  • electronic_background_elastic_analog_low
  • parameters_t1_high
  • solar_offset_nudge_nl
  • solar_background_nitrogen_low
  • elastic_counts_low_glue_coef_offset
  • t2_counts_high_glue_coef_slope
  • parameters_t2_high
  • nitrogen_counts_high_glue_coef_slope
  • t1_counts_high_glue_coef_offset
  • t2_counts_high
  • water_counts_low
  • electronic_background_depolarization_analog_high
  • water_counts_high_glue_coef_slope
  • t1_counts_high_glue_coef_slope
  • shots_summed
  • depolarization_counts_high_glue_coef_slope
  • elastic_counts_high_glue_coef_offset
  • t2_counts_high_glue_coef_offset
  • solar_background_elastic_low
  • solar_offset_nudge_t1
  • parameters_depolarization_high
  • solar_offset_nudge_t2
  • parameters
  • electronic_background_liquid_analog_high
  • liquid_counts_high_glue_coef_offset
  • parameters_water_low
  • elastic_counts_low_glue_coef_slope
  • merge_flags_high
  • electronic_background_nitrogen_analog_high
  • n2_cloud_check_value
  • elastic_counts_low
  • parameters_elastic_low
  • electronic_background_nitrogen_analog_low
  • water_counts_high
  • parameters_elastic_high
  • solar_offset_nudge_dh
  • nitrogen_counts_high
  • liquid_counts_high_glue_coef_slope
  • depolarization_counts_high_glue_coef_offset
  • solar_offset_nudge_eh
  • solar_offset_nudge_el
  • solar_offset_nudge_wl
  • merge_flags_low
  • t1_counts_high
  • solar_offset_nudge_wh
  • parameters_water_high
  • cloud_value_check
  • nitrogen_counts_low_glue_coef_slope
  • electronic_background_elastic_analog_high
  • nitrogen_counts_low
  • solar_background_water_low
  • parameters_liquid_high
  • depolarization_counts_high
more
sgp10rlprofasr1ferrC1.c1:
  • cal_asr_1
  • scale_add_lo
  • vert_scale_hi_2
  • cal_asr_error_low
  • asr_error_high
  • cal_factor_lo
  • cal_asr_low
  • bscat_err
  • scale_add_hi
  • asr_low
  • diff_trans_aerosol_corr
  • hi_cal_type
  • asr_1_error
  • tweaks
  • vert_scale_hi
  • cal_asr_1_error
  • shots_summed
  • asr_1
  • cal_asr_high
  • cal_asr_error_high
  • asr_error_low
  • cloud_mask
  • asr_high
  • scale_add_hi_2
  • corr_bscat
  • cal_factor_hi
more
sgp10rlprofmr1turnC1.c1:
  • mixing_ratio_low
  • vertical_resolution_bright_mode
  • mixing_ratio_1_error
  • pwv_rl_err
  • mixing_ratio_3
  • mixing_ratio_2
  • mixing_ratio_2_error
  • mixing_ratio_1
  • wv_rl_max_height
  • mixing_ratio_high
  • mixing_ratio_error_high
  • tweaks
  • calib_high_low
  • shots_summed
  • mixing_ratio_3_error
  • vertical_resolution_normal_mode
  • calib_factor
  • relative_humidity_over_ice
  • relative_humidity
  • diff_trans_aerosol_corr
  • pwv_rl_fraction
  • mixing_ratio_error_low
  • pwv_rl
more
sgprlC1.a0:
  • liquid_analog_high
  • liquid_counts_high
  • nitrogen_counts_high
  • shots_summed_elastic_low
  • shots_summed_water_low
  • t2_counts_high
  • t1_analog_high
  • depolarization_analog_high
  • depolarization_counts_high
  • water_counts_high
  • elastic_analog_low
  • shots_summed_depolarization_high
  • shots_summed_t2_high
  • shots_summed_elastic_high
  • water_analog_high
  • shots_summed_nitrogen_high
  • shots_summed_liquid_high
  • elastic_counts_high
  • shots_summed_t1_high
  • shots_summed_water_high
  • elastic_analog_high
  • elastic_counts_low
  • t2_analog_high
  • water_counts_low
  • t1_counts_high
  • shots_summed
  • nitrogen_counts_low
  • nitrogen_analog_low
  • n2_cloud_check_value
  • nitrogen_analog_high
  • cloud_value_check
  • water_analog_low
  • shots_summed_nitrogen_low
more
sgp10rlprofdep1turnC1.c1:
  • cloud_base_height
  • depolarization_ratio
  • cloud_depth
  • attenuation_flag
  • tweaks
  • cloud_top_height
  • calibration_factor
  • shots_summed
  • cloud_optical_thickness_aer
  • cloud_optical_thickness_n2
  • depolarization_ratio_error
  • cloud_mask
more

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