While the first two metrics, 4MDA8 and NDGT70 reflect peak ozone levels, SOMO35 represents mid-high ozone levels summed annually, and 3MMDA1 and AVGMDA8 represent high ozone levels over a 3 — 6 month season.
The other three metrics: SOMO35 (representative of mid-high ozone levels), and 3MMDA1 and AVGMDA8 (sensitive to high ozone levels) are summed annually or averaged seasonally.