Capping a very eventful last couple days that included a prestigious honor from the Clinton Global Initiative, participating in the People's Climate March in New York City, and accepting the position of U.N. Messenger of Peace, Leonardo DiCaprio today addressed delegates at the United Nations Headquarters, urging the international body to act on the climate crisis. 

The 39-year-old opened his speech by declaring that he's not an expert, but a concerned citizen wanting to help solve the environmental threats presented by climate change.  

"As an actor I pretend for a living. I play fictitious characters often solving fictitious problems," he said. "I believe humankind has looked at climate change in that same way: as if it were a fiction, happening to someone else’s planet, as if pretending that climate change wasn’t real would somehow make it go away."

After listing off a variety of worrisome environmental shifts already underway around the globe, DiCaprio decried those who continue to label climate change as weak science. 

"None of this is rhetoric, and none of it is hysteria. It is fact," he said. "The scientific community knows it, industry and governments know it, even the United States military knows it. The chief of the U.S. Navy’s Pacific Command, Admiral Samuel Locklear, recently said that climate change is our single greatest security threat.

"My friends, this body — perhaps more than any other gathering in human history — now faces that difficult task," he added. "You can make history ... or be vilified by it."

In addition to his speech, DiCaprio also made two other moves this morning, expanding his social media reach by joining the photo-sharing site Instagram and helping to launch a new website called Moment for Action., launched by 25 environmental organizations, (including Sierra Club, WWF, Oceana, and the Leonardo DiCaprio Foundation), offers both a petition to urge world leaders on climate change action, inspiring stories from individuals involved in solving the issue, and a fantastic video explaining the science behind the crisis. There's also an "Action Hub" where you can pledge to help organizations involved in everything from habitat conservation to solar energy dissemination. DiCaprio used Instagram to highlight the solar-focused 100%for100% campaign. 
Want to get involved? Jump here. Need an inspiring message to get you there? Check out DiCaprio's excellent U.N. address below.

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Michael d'Estries ( @michaeldestries ) covers science, technology, art, and the beautiful, unusual corners of our incredible world.

DiCaprio addresses United Nations, shares new climate action site
Newly minted U.N. Messenger of Peace tells delegates that 'now is the time for action' on climate change.