POINT MEASUREMENTS OF TROPOSPHERIC TRACE GASES AT TENERIFE BY A LASER-ABSORPTION TECHNIQUE

Field measurements of trophospheric trace gases have been performed at the Izana Observatory, Tenerife. The campaign was primarily orientat ed towards obtaining tropospheric OH concentrations. These concentrati ons are very low and generally do not exceed several 10(6) particles p er cm3 due to the high reactivity of OH. The detection method is based upon optical absorption spectroscopy and is therefore a multicomponen t device because different tropospheric compounds absorb in the same s pectral region which is used to monitor OH. The present results show t he quality with which measurements of such small concentrations can be carried out in ambient air and give a general proof of the suitabilit y of the Izana Observatory for such measurements.