When news got out a few weeks ago that car-rental company Avis had purchased the popular car-sharing service Zipcar, many reacted warily, wondering if the deal would kill Zipcar’s grassroots ethos. Others found such negativity overblown, calling the move not only unsurprising but smart, on both Avis’ and Zipcar’s parts. Whatever the future of Zipcar (and it’s hard to imagine Avis changing its model in any significant way), it’s undeniably helped us reimagine our relationship with cars – and maybe, at the same time, with our neighbors, too.

Over the 13 years since Zipcar’s founding, more of us have realized that the mobility we desire doesn’t require owning a car. In fact, for many of us city dwellers, especially young, single, and/or not-very-high-income ones, a car can be more of a burden than a convenience, once you factor in the price of gas and insurance and the hassle and expense of finding parking.

That doesn’t mean that we have no use for driving, however. Whether you’re car-free by choice or by circumstance, you’ve no doubt experienced the occasional surge of longing for a vehicle, when it’s pouring rain and the bus is late, or when you realize, walking home from the grocery store with several heavy bags, that you vastly overestimated your own strength and stamina. Zipcar (and its earlier peers, like Flexcar, with which it eventually merged) showed us that you don’t need to own a car to use one. Cars, like bikes and buses, can be just another element of a multi-modal transportation system -- a system that offers people a range of transit options and makes it easy to combine them.

“The U.S. has always been car-centric. I don’t see car-sharing itself changing that,” says Nick Cole, CEO of car2go North America, one of the latest companies to arrive on the sharing scene. “Not everybody’s going to be able to afford a car … but there’s going to be a need for this transportation.”

Zipcar saw that need and inspired a wave of other car-sharing operations to improve and build upon its model.

Conventional wisdom has it that the path to alleviating global hunger and poverty requires farming in the developing world to become more like agriculture in the U.S. But with American farmers now dealing with ever-more-frequent natural disasters and crippling drought, maybe it’s time they learned from their counterparts in the Global South, who have been facing similar ecological challenges for at least a decade now.

That’s what Danielle Nierenberg realized after spending three years traveling the developing world, meeting with farmers from Bolivia to Botswana to find out how they’re adapting to the changing climate’s effect on their livelihoods. Providing farmers around the world with a way to interact and share their ideas in a wiki-style format -- an “innovation database,” Nierenberg calls it -- will be a major component of Food Tank, the new food-focused think tank Nierenberg started with fellow activist Ellen Gustafson.

While Nierenberg has done extensive on-the-ground research for the Worldwatch Institute, Gustafson looks for ways to fix our food system through entrepreneurship and social activism. She co-founded FEED Projects, which sells tote bags to finance school meals for 60 million children around the world. The two women, both in their early 30s, kept running into each other at agriculture conferences dominated by old white men, and eventually, Nierenberg says, they decided “to combine our forces as women in this movement who have a lot of ideas.”

Food Tank’s website launches today, and in addition to an idea-sharing tool, Nierenberg says she and Gustafson hope to make it a clearinghouse for the most important food and agriculture reports of recent years. “I know I have a hard time finding where all the good reports are,” Nierenberg says. “For activists and policymakers as well as farmers, it will be a valuable tool.”

Last Thursday, I braved the hordes crowding Seattle’s convention center to offer their opinions on a proposed coal-export terminal, proposed for construction just north of Bellingham, Wash., that would ship coal arriving on trains from the Powder River Basin overseas to Asia. Buzz about this event -- a public hearing intended to gather input on what should be studied for the project’s environmental impact statement -- had been building for weeks. Turnout at previous hearings in other towns exceeded expectations (over 450 people showed up in Friday Harbor, the seat of a rural island county with a population of less than 16,000), prompting organizers to reschedule the Seattle hearing so it could be held at a convention center ballroom with a 2,000-person capacity, instead of a community college.

At a rally and news conference before the official hearing, I saw all the old environmental-protest standbys: a giant fish, a giant inflatable inhaler, an inflatable Earth, a hand-lettered sign reading “No coal train, yes Coltrane,” and last but not least, a lady dressed as Santa Claus comforting someone dressed as a polar bear. And much of the following testimony came straight from Bleeding-Heart Environmentalism 101: appeals from white people to think seven generations into the future, anti-coal slogans sung painfully to the tune of Christmas carols, etc. (When a group called the “Raging Grannies” took to the mike to offer such a performance, I heard one of the few terminal supporters in attendance groan “oh, God …” as her stereotype of crazy treehuggers was confirmed with frightening accuracy.)

But to me, those clichés were really more of a distraction from the impressively diverse range of interests opposed to the terminal. A pastor, a Muslim woman, and a Jewish man each spoke of the obligation to protect and care for God’s creation. A young mother-to-be who shared fears for her unborn son. Pete Knutson, a commercial fisherman for 40 years who runs Loki Fish Company in Seattle, spoke on behalf of “all those marine livelihoods” that would be affected not only by the huge increase in barge traffic carrying coal from the terminal out to sea, but also by the “deadliest catch of all” -- the ocean acidification caused by increased carbon emissions.

A few weeks ago, a series of mishaps hit Molly, 24, all at once: a roach-infested apartment, a sudden breakup, and she found herself sleeping in a friend’s basement, searching desperately for an affordable place she could move into with little notice. Easier said than done, as she lives in Seattle.

At the bus stop one day, Molly noticed a building of “aPodments” -- a trademarked brand of microhousing that has sprung up in Seattle over the last year like mushrooms after a rainstorm. (One local blog counts at least 15 projects constructed or in the works in just one neighborhood.) She called to inquire on a Friday and moved in on Monday. She has a three-month lease and pays $595 per month (utilities and internet included) for a furnished, dorm-sized room with a private bathroom, refrigerator, and access to a full-sized common kitchen.

Microhousing -- a catch-all term for ultra-compact apartments that sometimes share common spaces -- offers a way to reconcile rising urban housing prices with a financially struggling generation’s preference for city living. It’s proliferating in cities where the tension between those contradictory trends is most acute: Seattle, San Francisco, New York, Vancouver. San Francisco updated its city code to allow developers to build smaller individual units (a minimum of 150 square feet), and New York is reviewing design proposals for a pilot microhousing project of apartments around 275 to 300 square feet. Seattle’s approach has been a bit messier.

In the Emerald City, where housing prices are a constant lament (thought nowhere near as bad -- yet -- as D.C. or San Francisco), developers have found ways to work around city codes, creating structures that house dozens of people on what were once single-family lots. So far, the city is turning a blind eye. The result is that, for all city-dwellers’ disgust with McMansions and three-car garages, this tiniest kind of housing is now prompting passionate debate over the best approach to urban infill.

More than a week into December, I remain relatively unscathed by corporate Christmas chaos (although I’ll admit I caved to the craving for a Starbucks Peppermint Mocha). 'Tis the season to make you realize what a commercially saturated society we live in -- it bombards you from every side: the unbearable soft-rock holiday music playing on loop in the doctor’s office, the sad, cluttered “seasonal” aisle at the drugstore, the bus driver wearing a Santa hat.

I’m not even one of those wet-blanket scrooges who hate everything Christmas, either. I baked gingerbread last weekend, I get a thrill from the smell of Douglas fir on a cold morning, and I’ve been known to get verklempt if I hear Judy Garland singing “Have Yourself a Merry Little Christmas” after a bit too much eggnog. Actually, my sentimental enthusiasm for Christmas is what makes me cringe at the corporate crap even more -- for sucking the soul out of what should be a quiet, cozy, reflective holiday. (I think the film that best represents my feelings toward Christmas is The Homecoming, the 1971 made-for-TV movie that launched the series The Waltons. My family watches it every year, and I’m not the only one who cries. Go ahead, judge us.)

Given my growing distaste for forced consumerism, Buy Nothing (Corporate) Christmas is a welcome challenge. I kicked it off with a weekend arts-and-crafts binge, hitting up two local art fairs. At Art Under $100, held in a community center in one of Seattle’s more neglected (and thus probably soon-to-be-hip) neighborhoods, they had a DJ, snacks, and local IPAs for $2 a pop, so you could get buzzed while you checked out all the handmade pottery, jewelry, art, clothing, and knick-knacks. I bought a set of coasters made out of old 45s from a kid trying to raise money to go to film camp, a tie-dyed skirt from a woman who sews roller derby outfits for her daughters, and a couple pairs of found-object earrings from a vendor who showed me the design of the bee tattoo she wants to get. It was Christmas shopping farmers-market style, a rare opportunity to chat directly with the folks who make what you’re buying.

If you're worried about the health of American consumerism, don't be. Not even a bum economy can blunt Black Friday: Americans spent a record $52.4 billion over the four-day Thanksgiving weekend last year. This year, 147 million of us are expected to hit stores over Friday, Saturday, and Sunday; some folks have been camping out in line since Monday so they can be first to get trampled snag the best deals. I think it’s safe to guess that Grist readers aren’t really into that scene -- you have better ways to spend the day after Thanksgiving, as you let us know last year.

The creative ideas you shared then ranged from taking awkward family photos to making homemade cards to donating platelets -- all personalized takes on Buy Nothing Day, the annual call to reject the consumer freak-out that is Black Friday and refrain from spending any money at all that day. This year, Adbusters, the folks behind BND, are upping the ante by promoting Buy Nothing Christmas, a challenge to not just skip a day of consumerism but opt out of the entire holiday shopping season.

A group of Canadian Mennonites, not Adbusters itself, dreamed up Buy Nothing Christmas, and they offer some good arguments for why Christians ought to reject the corporatization of their most important holiday. (Liberal, progressive Christians exist, guys -- you’re reading the words of one. Stop associating us with Rick Santorum. Thanks.) Anyway, needless to say, every American could benefit from a break from the purchasing frenzy. This year, I’m going to go the extra mile and give Buy Nothing Christmas a shot -- and you should join me.

OK, I plan on cheating slightly. Certain younger cousins may be disappointed if I draw their names in the annual extended-family Secret Santa exchange only to offer nothing but an anti-capitalist lecture on the big day. I know part of the idea of Buy Nothing Day/Season is rejecting the cultural pressure to prove your love and devotion through materialism, and if you want to commit to that interpretation of it, more power to you.

But giving gifts can still be fun and meaningful if you know your present is unique and not something the recipient is going to see on a half-off rack at the mall the next day. Nothing kills the Christmas spirit like frantically navigating the downtown shopping district on Dec. 23, pawing through piles of V-neck sweaters and stacks of celebrity memoirs in search of something -- anything -- that would halfway satisfy that last person on your list. That kind of gift-giving makes me feel overwhelmed and empty at the same time, like when you’re starving for a hearty home-cooked meal and end up snarfing Trader Joe's Pretzel Slims (chocolate, please!) instead.

So instead of buying no Christmas gifts whatsoever, I’m going to abstain from patronizing corporations and chain stores this season. No fleece pajamas from Old Navy or DVDs from Best Buy. (I’m still deciding whether smaller, local, and/or sustainably minded chains will be fair game or not -- must I really boycott REI?) I wish I were one of those people who could avoid spending any money at all by giving everyone hand-knitted iPod cozies or painstakingly assembled scrapbooks for the holidays, but I don’t have a crafty bone in my body -- so I’ll have to settle for buying other people’s handiwork (what up, Etsy!), which isn’t really settling at all. Giving someone you love a truly unique present, and supporting a local and/or independent artist at the same time, kind of produces double levels of gift-giving warm fuzzies.

Do you plan on participating in Buy Nothing (or Buy Less) Christmas/Holiday Season? Tell us about it! We’ll follow up with some suggestions for alternatives to corporate gift-giving.

We need to talk about our national drinking problem. With more than half the country still devastated by drought, and all the experts saying we’d better get used to it, it seems like an appropriate time to discuss water conservation. Problem is, we're not too great at it: While much of the world lacks this most precious resource on a daily basis, we only need locate the nearest tap to quench our thirst -- and some of us still shell out cash to drink from a plastic bottle instead. How can we start to see water like the urgent issue it is?

In her book Taking on Water, Wendy Pabich explains the “diamond-water paradox”: “Although water is more useful than diamonds -- in fact, it is essential to life -- diamonds command a significantly higher price in the market.” She then quotes Adam Smith: “The things which have the greatest value in use frequently have little or no value in exchange; on the contrary, those which have the greatest value in exchange frequently have little or no value in use.”

Of course, water’s perceived low value has a lot to do with its perceived abundance -- and that abundance, as Pabich reminds us, is neither universal nor eternal. Water scarcity is not out of the question for the U.S.: The Ogallala aquifer, upon which nearly a third of irrigated U.S. farmland depends, is being depleted faster than increasingly scarce rainfall can refill it. The story’s similar for many of the world’s most important aquifers.

While chronicling her painstakingly thorough efforts to first measure, and then reduce, her household’s water consumption, Pabich targeted not just her direct use (turning on the tap, flushing the toilet, firing up any number of household appliances) but her overall water footprint -- how much water goes into the food she eats, the clothes she wears, and the daily products she uses. She pats herself on the back after calculating that she and her husband each use an average of 154 gallons of water per day, somewhere in between the average daily water use for all Americans (99 gallons) and other residents of Idaho, where they live (263 gallons) -- but then cringes remembering that “the average person in Mozambique subsists on slightly more than one gallon of water per day.”

As it turns out, when you take into account all the ways we directly and indirectly guzzle water, our secondhand consumption makes up much more of the total; Pabich found her food alone requires more water to produce than what she uses directly. Which means that your speed showers and rocks in the toilet bowl, while worthwhile efforts, can’t make up for the processes that produce your bread and blue jeans -- things that are harder for individuals to control.

Water conservation, like so many other sustainability issues, inevitably begs the question of whether individual actions can have any impact within a larger water-dependent system. Agriculture accounts for 70 to 80 percent of water use in the U.S., and thinking of that as a systemic problem, Pabich says, means “we can put that out of our heads and think that we don’t have much control over it. But when you look at the impact of our aggregate choices, we absolutely have something to do with it.” She points out that it takes 1,500 gallons of water to produce a pound of beef, “and in this country, we are consuming incredible amounts of red meat.”

While it’s a little frightening to see every element of your life as another leaky faucet, the good news is that cutting water use ends up conserving other resources as well.

Andrea Polli is what you might call a climate artist.

Where scientists mine data for evidence supporting or refuting their hypotheses, Polli looks at the same information and sees the potential for beauty. With degrees in both fine arts and computing, Polli works somewhere at the intersection of science, technology, art, and media. She translates raw data into sensory experience -- producing sonifications of Antarctic weather patterns and visualizations of stock-market activity; digital projections of particulate air pollution and interactive maps of sound in New York City -- like an audio version of Googlemaps’ Street view.

Polli has spent time everywhere from Antarctica to New Zealand to Taiwan, and is currently a professor in the University of New Mexico’s Art and Ecology program.

We caught up with Polli recently and talked about chaos theory, the sounds of climate change, and her artistic version of slow food.

Q. What led you to do the kind of work you’re doing now?

A. I had been working with computers all my life and creating little programs. But I never really thought of it as art until I went to grad school at the Art Institute of Chicago, and I had a mentor who caught me in the computer lab late at night and said, “What are you doing? Why haven’t we seen this stuff?”

A big article came out in Scientific American in ’85, and it had code in it. So me and my friends were typing in the code and programming these fractals. I started programming chaotic attractors to create algorithmic music: I was looking at these beautiful images of the butterfly attractor, and I thought, wow, this is just a mathematical formula and it makes this beautiful image -- I wonder if it would make beautiful music.

Q. How did you start focusing on climate science?

A. The butterfly attractor and other chaotic attractors are actually models of air moving through the atmosphere. Around 2000, I went on an art-science conference workshop, and met a meteorologist there. He said we could model something that happens historically almost exactly -- like a hurricane or a snowstorm. That led me to wonder what that might sound like. So we did the piece Atmospherics/Weather Works, which was a 16-channel sonification of a hurricane and a winter snow storm. The storm data created sound that was really dramatic, and I thought, well, would climate data create a kind of ambient sound?

[I was connected] with Cynthia Rosenzweig, who runs the climate research group at the NASA Goddard Institute [for Space Studies] up at Columbia. She’s being a scientist, very careful about what she says, and she starts telling me things that were really shocking. It made me really amazed at what was happening with climate change. So we did a project together called Heat and the Heartbeat of the City that used the climate models of their group. That’s really when I think I started to become actively involved in trying to address this issue of climate change however I could.

Emily McGinty was in high school when the ideas of Michael Pollan and other food-movement leaders began to spread, and she caught the bug. At Duke University, she says, “I was able to put a lot of these bigger questions about food in context,” connecting them to what she was learning in classes about economics and policy. She also had a chance to indulge her “honest interest in just getting my hands in the dirt” by managing a community garden on campus and working for the school’s new commercial farm.

Now a senior, McGinty has seen interest in food and farming issues slowly gather steam on campus over the last few years. At an elite university like Duke, where the most popular majors include biology, economics, and political science, “there aren’t clearly carved-out academic paths for students interested in studying anything food-related,” she says. “I’ve been lucky enough to watch that change bit by bit.”

The commercial farm started as a hypothetical class project. Now in its second growing season, and tended by work-study students, the farm grows bulk produce to be sold to campus dining halls, which are run by Bon Appetit Management Company (BAMCO). The food-service company has a reputation for leading the way on local food, humane meat, farmworker justice, and sustainable seafood. It's also focused on building and supporting campus food networks.

BAMCO’s latest project recognizes the need for student farms to connect not only with hyper-local markets, but with each other, so they can share resources and support. Campus Farmers, an online social network that allows them to do just that, officially launched on Oct. 24 (World Food Day), as a joint effort by BAMCO and Kitchen Gardeners International (KGI). Campus Farmers is a subset of KGI’s larger network.

Most laying hens in the U.S. are raised in cages with up to eight other birds, with barely enough space to turn around, much less walk. They eat antibiotic-laced feed made from genetically engineered grain and the ground-up feathers of other chickens. Raising chickens this way is so inhumane it has been banned in the European Union and it will be banned in California starting in 2015, but a full 95 percent of laying hens in the U.S. still live in cages. Like so many other parts of this country’s conventional food system, the practice keeps prices low and profits up by not accounting for its hidden costs to human health and the environment.

Austin’s Vital Farms is working to change that. Since 2007, the company has been selling its pasture-raised organic eggs -- sourced from a network of small family farms in Texas and nearby states -- at Whole Foods and other natural grocery stores around the country. The largest producer of this type of egg in the country, Vital Farms made $4.9 million in revenue last year. With this kind of clout, the company can offer support, guidance, and market access for egg producers looking to transition to raising birds on pasture -- slowly but surely building the ranks of humane chicken farms in the U.S.

Third-generation Arkansas egg farmer Michael Cox is one of those producers. His family had already converted its operation to a cage-free, organic one, but the birds were still confined indoors (USDA organic standards require that the birds have “access to the outdoors,” but that can mean nothing more than a small porch attached to the henhouse). “We had heard about [pasture-based farming] and were really interested in doing it, but didn’t know where to start or who to talk to,” Cox says.

Cox got in touch with Vital Farms when CEO Matt O’Hayer called to inquire about buying feed, and that first phone call led to a visit to Vital Farms’ 27-acre site in south Austin, where O’Hayer first perfected the pasture-based model he now passes on to farmers like Cox. Now, in addition to producing eggs sold under the Vital Farms name, Cox connects with other farmers in his area interested in switching over to a pasture-raised operation. He said he sometimes gets a dozen phone calls a week from curious farmers.

For conventional egg producers, the Vital Farms model -- and the higher prices its humanely raised eggs command -- has undeniable appeal: “You can find a farmer who used to raise 60,000 or 70,000 birds for Tyson, and we can give them 15 or 20 percent of the birds they've had, and they can actually make a better living,” Cox explains. “It’s a win-win for everybody; it’s better for farmers and birds.”