Top Carnival Corp. executives are due back in court to explain what the world's largest cruise line is doing to reduce ocean pollution.

A hearing is set Wednesday in Miami federal court for an update on what steps Carnival is taking. Chairman Micky Arison, who also owns the Miami Heat, and CEO Arnold Donald are both expected to be there.

Earlier this year, Carnival admitted violating probation from a 2016 criminal pollution case as its ships continued to cause environmental harm around the world since then and was hit with a $20 million penalty. That comes on top of a $40 million fine imposed in the original case.

Carnival operates more than 100 ships across its nine cruise brands and sails to more than 700 destinations.