Repeatability of the Seasonal Variations of Ozone near the Mesopause from Observations of the 11.072-GHz Line

Abstract

Ground-based observations of the 11.072-GHz line of ozone were made from January 2008 through the middle of September 2011 to estimate the maximum in the nighttime ozone in the upper mesosphere at an altitude of about 95 km for a region centered at 38°N, 290°E. The measurements show seasonal variation with a high degree of repeatability with peaks in ozone concentration about a month following each equinox. A significant increase in ozone concentration above the yearly trend occurred in 2010 from mid-November until the end of December, which the authors attribute to delay in the start of the meridional circulation for the austral summer of 2010.