DQRID : D160720.2
Start DateStart TimeEnd DateEnd Time Data Quality Metric
04/23/20160954Open Ended0954Suspect
more
Subject:
ASI/AETH/M1 - Negative black carbon mass
DataStreams:asiaosaethM1.00, asiaosaeth1spotM1.a1
Description:
Due to a design flaw - separate plumbing lines on the sample and reference lines - in a 
small laboratory volume differences in the RH between these two lines will oscillate when 
the laboratory A/C cycles on and off. This is a known problem with the Aethelometer model 
(AE-31) currently deployed in the MAOS.
Suggestions: 
To help suppress these oscillation, two approaches are available for the end user to 

do: (i) use a 3-pt running average on the original data or (ii) a 3-pt boxcar average. 
While the former will retain the 5-min time resolution, the independence of adjacent data 
measurements will be lost. In the latter, each averaged data point will be independent 
from the previous measurement, but the temporal resolution will be reduced to 15 -minutes. 
Application of either averaging approach greatly diminishes the oscillations.
Measurements:asiaosaeth1spotM1.a1:
  • sample_flow_rate
  • optical_attenuation
  • reference_intensity
  • time_offset
  • spot_size_area
  • base_time
  • bypass_fraction
  • wavelength
  • sample_dark
  • equivalent_black_carbon
  • sample_intensity
  • specific_attenuation_sigma
  • reference_dark
more
asiaosaethM1.00:
  • Raw data stream - documentation not supported
more

Close this window