More than 200 picnickers gathered on the lawn outside Queen's University as part of a global day of action on climate change.
Marches, events and rallies have been organised in more than 90 cities around the world as part of a global protest calling on governments to accelerate climate action.
It comes as heads of state travel to New York tomorrow to attend UN Secretary Ban Ki-Moon's historic Climate Summit.
Campaigners are calling on world leaders to take ambitious action to curb emissions and stop climate change making people hungry.
More than 2,000 marches were held around the world yesterday, and more than 100,000 people were thought to have attended the New York rally, making it the largest ever turnout of people to press for action over climate change.
The Hollywood actor Leonardo DiCaprio was attending, having been appointed as a UN representative on climate change last week.