Story highlights Clement studied the impact of rising sea levels on Native American tribes in Alaska before being reassigned

Clement was one of 50 Interior employees told early June that they would be involuntarily reassigned to other positions

Washington (CNN) The Interior Department employee who blew the whistle on the Trump administration for reassigning him from measuring climate change to a different department has resigned.

Joel Clement, who worked at Interior for more than seven years and continued on in his new accounting role for three months, said he left after losing all hope things would change.

"It was a really difficult decision. I felt strongly about serving in the civil service, and it's really hard to leave, but Secretary (Ryan) Zinke is really acting against all of the issues that are important to the health and safety of Americans and natural resources, he told CNN.

"The checkmarks in the cons column just kept adding up," Clement added.

Reached for comment, an Interior spokesperson said: "The Department does not comment on ongoing matters such as whistleblower complaints. We look forward to working with the Office of Special Counsel to address any questions they might have about this matter."

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