With the oceans facing threats such as plastic pollution and global warming, World Oceans Day aims to raise awareness with a series of events. A healthy world ocean is critical to our survival, organizers say.
People across the globe on Saturday gathered to clean up beaches and celebrate the importance of oceans in honor of World Oceans Day.
More than 1,000 events have been scheduled.
Many people attended beach cleanups or information sessions, while others made art installations and attended ocean-themed exhibitions.
The oceans cover about 70% of the Earth's surface and provide 70% of the oxygen we breathe.
The giant swathes of water also absorb around a third of all man-made CO2, and 90% of the excess heat created by those emissions goes into the sea.
Artists Gepetta and Salvabarche in Milan made an installation to raise awareness for sustainable fishing
Among the problems the ocean is facing, plastic pollution is one of the biggest.
According to the United Nations, 13,000,000 tonnes of plastic find their way into the ocean every year, which kills 100,000 marine animals annually.
Most plastics in the ocean are expected to remain intact for decades or even centuries after use, but those that erode end up as microplastics, which are then consumed by fish and end up in the global food chain, the UN said.
Read more: Plastic waste and its environmental impact
Next oceans report 'fairly grim'
The UN Intergovernmental Panel on Climate Change, which released a landmark report in October 2018 warning of the effects of global temperature rises, is due to publish its latest assessment on the state of oceans in September.
"The IPCC report will be fairly grim," Lisa Speer, director of the international oceans program at the Natural Resources Defence Council, told French news agency AFP.
The last IPCC assessment, in 2014, predicted that sea levels could rise as much as one meter (3.3 feet) by the end of the century.
But newer studies using more varied scenario planning have said that current warming trends could see the ocean rise as much as two meters by 2100.
Dan Laffoley from the International Union for the Conservation of Nature said there were four main threats facing the world's oceans: surface warming, ocean heating, deoxygenation and acidification.
"We scientists are taken aback by the scale, depth and speed of the change," he said.