This blog is part of our Inspired Ethonomics  series. Patti Prairie is the CEO of Brighter Planet, a startup whose purpose is to help manage our environmental footprint, you can follow via their blog 
We at Brighter Planet regularly come across rankings  of green  airlines , but it's not always easy to tell which metrics they're based on. Like anything else in the climate change arena, if you want to cut through the rhetoric and hand waving, you have to go right to the data. Naturally, that's just what we did.
We took 9.2 million flight records from a government database and ran them through our climate emissions engine. (Fun fact: this processing, including cross-tabulation and indexing, takes about 15 minutes on a standard household computer.) We analyzed these flight segments accounting for over a dozen characteristics, including aircraft size, seat class and pitch, engine type, fuel efficiency (unlike automobiles, this involves a different third-degree polynomial function for each representative aircraft model), capacity, freight payload, and revenue.
Our goal for this analysis was to determine how much *fuel* was used by each passenger. From a climate standpoint, this is the key metric: since we know how much carbon is in each liter of jet fuel, we can deduce exactly how much greenhouse gas impact each passenger is responsible for.
The results were surprising.
Given all the hype about the routing efficiency and modern fleet attributes of the new-era "budget" airlines, you'd think they'd dominate the top of the list. But in reality, only JetBlue makes the cut--indeed, it comes in first place. The other major discount shops, Airtran and Southwest, come in dead last on our list, producing 60% and 40% more emissions per passenger, respectively, than JetBlue.
Continental, one of the big-five "old guard" airlines, ended up in second place; impressive considering a legacy fleet and timetable. Virgin America's chief Richard Branson, a vocal climate activist, led his airline to a respectable third place.
Brighter Planet (www.brighterplanet.com) helps people manage their environmental footprint. The clean-energy start-up is pioneering fresh green solutions that are accessible to everyone, fit one's lifestyle, and are fun to share. To date, more than 150,000 customers have used the company's climate change solutions, the Brighter Planet Visa debit and credit cards and Offsets by Brighter Planet, to invest in reputable American renewable energy projects.
This is the first post in a series we'll be doing about a new era of climate action, one that is driven by data and values hard information over corporate slogans and press releases. Have an idea for us? Something to investigate? Shoot us a note at email@example.com.