Conservation group Greenpeace warned that the environmental impact of the Fukushima nuclear crisis five years ago on nearby forests is just beginning to be seen.
The Eiffel Tower turned green Sunday for the opening of the Paris climate conference, marking the launch of an art project that will see "virtual trees" grow on the landmark to support reforestation.
Thousands turned out for climate change marches across the Asia-Pacific region, part of a weekend of action across the globe to demand results from next week's historic Paris summit.
Prime Minister Justin Trudeau will meet leaders of Canada's provinces and territories to hash out a cohesive climate strategy a week before key international talks in Paris.
French President Francois Hollande called for the creation of an "environmental security council" to verify and enforce measures to be adopted at a year-end UN climate summit.