AE43 Aethalometer
The AE43 is a multi-wavelength aethalometer used for measuring black carbon aerosol concentrations in the atmosphere.
Data Format
- File format: CSV file
- Sampling frequency: 1 minute
- File naming pattern:
[!ST|!CT|!FV]*[!log]_AE43*.dat
- Timestamp column: StartTime
- Configuration tracking: Uses SetupID for configuration management
Measurement Parameters
The AE43 provides black carbon concentration measurements at seven wavelengths:
- BC1-BC7: Black carbon concentrations at different wavelengths (ng/m³)
Data Processing
Data Reading
- Parses timestamps from the StartTime column
- Automatically identifies and selects the latest configuration data (SetupID)
- Extracts black carbon concentration data for seven wavelengths
- Groups data by SetupID to handle configuration changes
- Includes Status column for quality control
Quality Control
-
Instrument Status Check:
- Filters data based on instrument status codes:
- Status = 1: Tape advance (tape advance, fast calibration, warm-up)
- Status = 2: First measurement – obtaining ATN0
- Status = 3: Stopped
- Status = 4: Flow low/high by more than 0.5 LPM or F1 < 0 or F2/F1 outside 0.2 – 0.75 range
- Status = 16: Calibrating LED
- Status = 32: Calibration error (at least one channel OK)
- Status = 384: Tape error (tape not moving, end of tape)
- Status = 1024: Stability test
- Status = 2048: Clean air test
- Status = 4096: Optical test
- Removes data points with other status codes indicating instrument problems
- Filters data based on instrument status codes:
-
Value Range Check:
- Removes physically impossible values (negative or > 20000 ng/m³)
-
Data Representativeness:
- Requires at least 50% of expected data points in each 1-hour window
- Ensures temporal consistency of measurements
-
Complete Record Requirement:
- Ensures data completeness across all wavelengths
Output Data
The processed data contains the following columns:
- Time index: Data acquisition time
- BC1-BC7: Black carbon concentrations at seven wavelengths (ng/m³)
Notes
- The AE43 provides real-time black carbon concentration measurements, useful for distinguishing between biomass burning and fossil fuel combustion contributions
- Supports data filtering based on instrument status codes
- Automatically handles configuration changes and duplicate timestamps
- Maintains data integrity across configuration changes using SetupID