slv.measurements.mobile.calibration.CAL_SOURCES#

slv.measurements.mobile.calibration.CAL_SOURCES = ('pipeline', 'manual_cal', 'uncalibrated')#

Provenance tag carried by every TRAX observation in cal_source:

  • pipeline: pipeline-calibrated value (CH4d_ppm_cal from the calibrated level).

  • manual_cal: the lgr_ugga_manual_cal instrument (installed 2023-11-18, when the on-board tank was removed; a tank ran again in 2024 and the last pipeline calibration is 2024-08-20); the pipeline applies no calibration, so this is the analyzer’s raw CH4d_ppm.

  • uncalibrated: raw CH4d_ppm from the lgr_ugga qaqc level inside a window listed in trax_uncalibrated_windows.csv (tank empty, no valid reference). Same treatment as manual_cal; the LGR’s gain was within 0.5% of unity on either side of every window.