Is it just a coincidence that this year, Earth Week starts on 4/20, which for many on the west coast is "National Pot Smoking Day"? Regardless, this is an opportunity to voice the best, brightest and greenest ideas for how to save the planet from certain doom—and make a few points about our global priorities in the process.

The big news last week, that could mark the end of our generations of delusion about carbon dioxide, was the EPA's announcement that carbon dioxide, along with methane, nitrous oxide, hydrofluorocarbons, perfluorocarbons and sulfur hexafluoride, are indeed heat-trapping gases that speed the greenhouse effect. It was a long time in coming, especially in light of the fact that the first murmurs about carbon dioxide's nefarious side came out in 1896 with Swedish thinker Svante Arrhenius' paper titled "On The Influence Of Carbonic Acid In The Air Upon The Temperature Of The Ground."

But we won't dwell on all our hubristic and consumptive impulses that led the earth to this point. Rather, we'll spark conversations on the Transition Movement, going off-grid, the elusive green mind, China's brown air, cars that are smarter than you are, and just when and how sea levels will start to lap at your front door.

It's all this week on Big Think.