Gov. Jay Inslee says he's signing an executive order that sets into motion a process to determine how to reduce carbon pollution in Washington state.

Inslee said at a news conference Tuesday that climate change is one of the greatest challenges facing the state, and that the time to act is now.

A carbon emissions reduction task force will be formed and will come up with proposals that would be introduced in the 2015 legislative session.

Inslee says there's no doubt that a 2008 state law requires that the state to reduce greenhouse gas emissions.