Plastic in the ocean is predicted to triple by 2025 if present-day practices don't change.
A recent report from the U.K. Government Office for Science says about 70 percent of all litter in the ocean is plastic. The study says plastic doesn't decompose but instead breaks down into smaller pieces and ends up on beaches or in animals' digestive tracts.
And plastic isn't the only problem. The report lists chemical pollution, rising temperatures and rising sea levels as some of the biggest challenges for marine environments.
Researchers behind the report say a major part of fighting the threats is to increase awareness about the issue. And they say more work needs to be done to learn about the ocean and the affects of climate change.
Additional reporting from Newsy affiliate CNN.