Mount Sutton, Quebec - Ground Level Ozone Study

Ground level ozone and meteorological parameters were measured at the Mount Sutton research site from October 1986-June 2008. The main objectives of these measurements were:

1. to characterize high elevation (845 m.a.s.l.) ozone levels in this rural region; and 2. to determine long term ozone trends, particularly background levels.

Ozone was measured with a commercial Thermo Environmental Instruments Model 49 instrument based on the principle of ultraviolet absorption by Ozone. Calibrations were performed approximately every 3-4 months and were referenced directly to the National Institute of Standards and Technology (NIST), in Gaithersburg, Maryland, U.S.A.. Calibrations were usually within 1% of the mean calibration factor and it is estimated that the final hourly corrected O3 mixing ratios are accurate to within ± 2% or ± 1 ppb, whichever is greater. Meteorological instrumentation was mounted on a tower on the roof of the sampling hut. Measurements were made of temperature and relative humidity, pressure, total ultraviolet radiation, total spectrum solar radiation, precipitation, wind speed and wind direction. Ozone measurements at this site continued after 2008 under the auspices of the Canadian Air and Precipitation Monitoring Network (CAPMoN). The CAPMoN measurements are made under the name Roundtop Ridge and the data are available through the CAPMoN data files.