Real Time SAOZ Data available here
Consolidated V3 SAOZ Data available here

For more information about the SAOZ please contact Dr. Andrea Pazmiño

The SAOZ (Système d’Analyse par Observation Zénithale; Pommereau and Goutail, 1988) is guest instrument at the PEARL Ridge Lab on loan from the Service d’Aeronomie (now LATMOS) of the Centre National de la Recherche Scientifique (CNRS) in France.  It has been operated at PEARL since 2005 for the annual ACE/OSIRIS Arctic Validation Campaigns, initially each spring and then year-round from 2015 onwards. The instrument is an automated, zenith-sky-viewing UV-Visible spectrometer that operates in a similar manner as the GBSs to measure atmospheric gases using scattered sunlight.  SAOZ instruments are widely used around the world as a network, and are specifically designed for making stratospheric measurements in polar regions. SAOZ makes measurements of UV and visible spectra (300-600 nm wavelength range with a resolution of about 1.3 nm).  It looks directly upwards (e.g., zenith-viewing) to make its observations primarily when the sun is close to the horizon (at solar zenith angles greater than 81 degrees), providing very good sensitivity to gases in the stratosphere.

Figure 1:  SAOZ installed on the roof at the PEARL Ridge Lab.  It is tied down tightly to prevent it getting damaged during severe wind and snow storms.  Photo Credit: Paul Loewen

The Differential Optical Absorption Spectroscopy (DOAS) method is used for retrieving stratospheric gas column amounts of ozone and NO2 from the SAOZ measurements in a similar way to that used for the GBS systems.  These results have been used to validate measurements from the Canadian Atmospheric Chemistry Experiment (ACE) and Optical Spectrograph and InfraRed Imager System (OSIRIS) satellites and many European satellite instruments.  Most of the SAOZ instruments are part of the worldwide Network for Detection of Atmospheric Composition Change (NDACC).  More information on the SAOZ instrument and its network can be found here.