Harvard University has reduced its greenhouse gas emissions by 30 percent, completing a goal it set back in 2008 to cut its levels regardless of growth, President Drew Faust said Thursday.

In a letter to the university community, Faust said the feat was accomplished by an “extraordinary collaboration among staff, students and faculty, and I am grateful for their commitment.’’

Harvard’s goal was to reduce its 2006 emissions levels 30 percent by 2016, Faust said. The goal took into account campus growth over that period, a university spokesman said.

“Our work, however, has just begun,’’ Faust wrote in the letter.

The university has convened a task force to determine the next phase of its climate commitment, and the group will make its recommendations by the end of the academic year.

The school is also funding a three-year course and research project “to study off-site emissions reductions projects,’’ the spokesman said.

“Harvard must continue to drive progress related to climate change, sharing what is known, expanding what is known, and acting on what is known,’’ Faust wrote.

“Climate change is a threat to our future, and it deserves nothing less than our best efforts in the present.’’

Dylan McGuinness can be reached at dylan.mcguinness@globe.com. Follow him on Twitter at @DylMcGuinness.