Brewer Instruments 16 & 178
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* Verion 1.0 is based on the calibration of the instrument as
* described by De Backer and De Muer [JGR, 96, 20711-20719, 1991]
* and confirmed by calibration visit in Sep 1994
* Calibration level adjusted following SL readings


* Verion 1.0 is based on the calibration of the instrument as
* described by De Backer and De Muer [JGR, 96, 20711-20719, 1991]
* and confirmed by calibration visit in Sep 1994
* result calibration visit IOS in May 2003 taken into account
* result calibration visit IOS in May 2006 taken into account
* Calibration level adjusted following SL readings

Dobson Instrument #040
----------------------

Staring from 1971

* Verion 1.0 includes the adjustments following WMO calibrations
* up to June 2000 (IC MOHp2000-I)
* Calibration level adjusted following SL readings
* Data are corrected for SO2 influence
* [De Muer and De Backer, JGR, 95, 11903-11911, 1990]