Greenpeace volunteers pose for a group portrait before performing an 'ocean wave' in Douala, Cameroon at an event in the lead-up to World Oceans Day.

From Santiago to Bangkok, London to Johannesburg, Greenpeace volunteers and supporters create human waves across 23 countries to call for the protection of our seas and the creation of a network of ocean sanctuaries covering 30% of international waters by 2030.