The world's frozen areas lost an average of about 87,000 square kilometers (33,000 square miles) a year from 1979 to 2016, and the period of annual freeze has shrunk by more than a week over the nearly four-decade period.
Twenty-four countries and the E.U. have agreed to create three marine parks, which would ban fishing and other industrial activity. But to become a reality, China must also agree.
