"The 11th Hour” is a saying that refers to the last possible moment when change is possible. It's also the title of a movie being released in the USA next week on the topic of environment and climate change.

Produced and narrated by Leonardo DiCaprio, The 11th Hour looks at how we have gotten to the point we have, the impact of humanity on Earth's ecosystems, what the future likely holds if we continue with a "business as usual" approach  - and what we can do to change that from happening.

Leonardo DiCaprio is sure to be a big drawcard for the movie, but he's also assembled a distinguished panel of over 50 scientists and influential people who present their views throughout the documentary. These people include Kenny Ausubel, founder of the Bioneers Network, James Woolsey (Former CIA head), physicist Stephen Hawking and former Soviet Prime Minister Mikhail Gorbachev.

Here's a preview of The 11th Hour:

I'd heard that Leonardo DiCaprio was a "greenie", but often with celebrities the environmental streak is rather thin and shallow. That doesn't seem to be the case with Leonardo - here's an interesting recent interview with the actor.

Regardless of how green any of these celebs really are, they are doing a great service by bringing these issues to the forefront. It does bug me to see people pointing at aspects in their lifestyle that aren't so environmentally friendly with such venom. We're all in this together and making changes as we can is important and should be applauded; however big or small those changes may be.

While many who will see The 11th Hour will already be "converted", hopefully we can all drag someone else along who to see it who is undecided on the issue of global warming or just doesn't get the seriousness of the issue. The 11th Hour is a great follow up to Al Gore's An Inconvenient Truth and will certainly help build on the momentum that Mr. Gore's movie generated.

The movie isn't all gloom and doom by any means; it does offer a message of hope. I  particularly liked this quote towards the end of the preview: "What a great time to be born, what a great time to be alive, because this generation gets to completely change the world."

That's optimism :)

Although release date in the USA is August 17, I'm not sure when The 11th Hour will start screening in Australia; so if you're one of the lucky folks who get to see it on release day, I'd love to read your thoughts on the documentary!

By the way, another great movie with DiCaprio is Blood Diamonds. While a fictional piece, it's based on the very real issue of what are known as conflict diamonds -  diamonds mined under terrible conditions and sold in order to finance war. It's a disturbing movie but really drives home the point that our desire for precious stone and metal jewelry isn't only bad for the environment, it's helped finance the killing of thousands and the displacement of millions of people.