CAMBRIDGE, Mass. (AP) – Al Gore returned to his alma mater to help Harvard University launch its new greenhouse gas reduction effort.

The former vice president and 1969 Harvard graduate, told a campus audience on Wednesday that it’s time to find ways to make better use of knowledge to save the global environment.

Riffing off Harvard’s Latin motto of “truth,” he said the challenge is to find truth in the climate crisis and “use that as a basis of a new concept of who we are.”

Gore, who has shared the Nobel Peace Prize and starred in the Academy Award-winning global warming documentary “An Inconvenient Truth,” also received an annual service award.

Harvard has a goal of reducing its greenhouse gas emissions 30 percent by 2016.