Today is Ash Wednesday, marking the beginning of Lent — the 40-day period of self-denial for Christians that ends on Easter, when you’re given the go-ahead to snarf down Cadbury eggs to your heart’s content. A few standard vices that people temporarily quit include sweets, sex, Big Macs, $5 lattes, and Katy Perry music videos.

But this year, Catholics all over the world are making a statement with their abstinence by giving up food and carbon-intensive habits to raise awareness for climate change. One of the main goals of the climate justice fast, organized in part by the Global Catholic Climate Movement, is to urge political leaders to commit to climate change action.

Yep, no meals and no joy rides in the family Hummer for 40 days. You may worry about the health implications of the whole “no meals” thing, but man does not live on bread alone — and also, this isn’t a continuous fast. It’s a chain of one-day fasts that will spread across the globe: Each of the 45 countries that signed up for the climate justice fast were assigned a day to abstain. Peru, the site of the most recent U.N. climate talks, is starting the fast-ivities today. And just in case you want to support your Catholic, climate-caring friends — or just avoid them while they’re hangry — the U.S. will participate on March 16.

We don’t recommend forgoing food for 40 days (or, in fact, skipping more than a couple meals), but the idea of a “carbon fast” has a real nice ring to it. Hail yeah, Mary.

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