Lone Tree Council's Terry Miller, left, leads a group in a pro-environment pledge during the Global Climate Rally on Sunday at the Tridge. Participants assembled at the Tridge holding large 350 numbers, referring to 350 parts per million as the upper safety limit for atmospheric CO2. The group posed for pictures that could be shared via social media and chanted pro-environment phrases led by Miller and Saginaw Valley Sustainability Society's Pat Race.