Preliminary results

21 september 2003 was one of the perfect days for a Langley calibration. The figure below shows Langley regressions for all instrument channels (horizontal: airmass, vertical: instrument counts). The atmospheric composition was so stable that almost all measurements were within 1 instrument count of the Langley fit. Such a perfect result can only be obtained outside the turbid and variable boundary layer, i.e. at a high-altitude site in the free troposphere.