8 June every year
World Oceans Day has been unofficially celebrated every 8 June since its original proposal in 1992 by Canada at the Earth Summit in Rio de Janeiro, Brazil. It was officially recognized by the United Nations in 2008. Since then it has been coordinated internationally by The Ocean Project with greater success and global participation each year.
The theme for this year i.e. 2015 is Healthy oceans, healthy planet.