Supermarket shelves may soon be filled with labels that calculate the carbon footprint of everything from candy bars to hamburgers

You might feel guilty every time you eat a hamburger: you might count the calories you are consuming, wonder if the saturated fat will clot your arteries or worry about the sad cow that became your meal. Well, now, you have to add a new reason: the impact of that burger on global climate change.

The eco-impact of Americans’ yearly production and consumption of cheeseburgers is equal to the emissions of between 6.5 to 19.6 million SUVs, depending on the fuels used in transporting the ingredients.

That’s the shocking result of a life cycle assessment of cheeseburgers conducted by Jamais Cascio, a San Francisco-based futurist and ethicist who blogs about the intersection of technology, the environment and culture.

He arrived at that number by combining data published by scientists on the carbon dioxide emitted during the manufacturing of each ingredient in a cheeseburger with average figures for cheeseburger consumption in the U.S.

“It’s really easy to turn this into a ‘don’t eat cheeseburgers’ story,” warned Cascio. “Rather, these startling numbers should show us that everything we do has a greenhouse impact.”

Read More: Check out the details of Jamais Cascio’s cheeseburger study, in which he outlines how the carbon footprint of our consumption of cheeseburgers compares to that of SUVs.

In fact, while all the public’s attention has been focused on the impact of the oil and automobile sectors on global warming, governments and activists are starting to measure the carbon footprint of food.

And soon, a new incarnation of the multiple labels that already exist will show up on bananas, potato chips and tomatoes: the carbon footprint label.

This new label on the block attempts to quantify exactly how much greenhouse gas was generated in producing and transporting food.

The massive British grocery chain Tesco is one of the leaders of the carbon labeling movement. Tesco recently announced plans to label 30 specific products, while other companies ranging from Coca Cola to Cadbury to Kimberly Clark have volunteered to develop similar labels for products including soft drinks, candy bars and diapers.

Customers will be able to count their footprint just like they can count calories or grams of fat.

American retailers are mostly watching from the sidelines. Wal-Mart officials, who are committed to reducing the massive company’s carbon footprint by about 20 percent over the next five years, are reportedly studying the labels.

And even those companies that are not yet developing a label for their own products are closely following the trend. According to a survey recently released by the law firm Pillsbury Winthrop Shaw Pittman LLP, 60 percent of 600 companies said they worry about the potential compliance costs associated with carbon footprint legislation.

Britain’s lead seems to reflect more than just the usual greater sensitivity of Europeans to environmental issues. The Carbon Trust, a private company set up and funded by the British government designed to accelerate the transition to a low carbon economy, has stimulated much of the best work on carbon labels. It works in partnership with producers and retailers, allowing companies to benefit from each other’s experience.

In our interactive graphic, learn about how some eco-friendly companies like Stonyfield Farm and Tesco are trying to go green (and make you go green, too).

Setting a Standard

The carbon footprint label is a work in progress. To be accepted it must be as credible as labels that measure calories or carbohydrates or other product characteristics that guide shoppers’ choices. And that is a problem.

The Tesco labels, and those popping up elsewhere, are an effort to measure all the greenhouse gas emitted throughout a product’s life cycle. Essentially, analysts try to map the supply chain involved in getting a product to market including raw materials, manufacture, distribution and disposal. Once a supply chain map exists, each step has to be analyzed to determine how much greenhouse gas is produced.

This is potentially a massive effort, and choices have to be made about what to include and what to exclude. For example, in Britain, the current standard is to try to measure 90 percent of the inputs into any product, and to include only processes that directly affect production. That may prove to be too difficult a process to sustain.

One part of the problem is that any product’s footprint constantly changes. “The carbon footprint for a particular product, at a particular point in time, is different than it will be in twenty minutes, or a day, or a month later. So, if we look at the carbon footprint of imported strawberries in January versus in March, the number is going to be different,” said Phil Lempert, a California-based consumer trends tracker who calls himself the “Supermarket Guru.”

Due to this numerical variability, Lempert added, “I’m not sure that it adds any valuable information for a consumer. Until we can have a bullet-proof standard that consumers can really rely upon, most of these logos and labels are really pretty meaningless.”

Our interactive graphic walks you through the carbon footprint of each step in the process for a bag of Walkers potato chips, explaining the details that affect each step from raw potatoes to supermarket shelves.
For starters, how far back does the analysis for food have to go for it to be accurate? How accurate are carbon output measures of vastly different processes? Is it OK to use averages? Can measures be standardized across countries in order to compare, say, the carbon footprint of strawberries produced in New Zealand and those grown in New Jersey?

Because these life cycle assessments are so complicated, some experts think that the carbon footprint labels are not really meant to give shoppers actual, verifiable scientific data. “They are about information,” remarked Cascio.

He believes that calculating the carbon footprint does not need to be one hundred percent accurate because it would be “correct within an order of magnitude and is primarily for raising awareness.”

He hopes, for example, that his study of hamburgers will make Americans more aware of the connections between their love of burgers and the changes in
the weather.

Is Buying Local Best?

An easy answer to reducing your carbon footprint should be to buy local. After all, transport of food by plane, train and boat exacts a heavier toll on the atmosphere than buying from the local farmers’ market.

But measuring the carbon dioxide output is a little more complicated than counting up the distance those grapes just traveled from South Africa to Fargo, N.D. “The proportion of climate change gases used to transport food is trivial compared to what happens on the farm or in processing,” said Rita Schenck, from the non-profit Institute for Environmental Research and Education.

At the Greenmarket in New York’s Union Square, FLYP talked to grocery shoppers to find out how they try to incorporate a lower carbon footprint in their diet. Watch the video.
Production methods make a big difference—whether the grower used a lot of fertilizers or pesticides—as do the general growing conditions.

A 2005 study by the British government found that in some instances it was more energy efficient to import tomatoes from Italy than grow to them in U.K. Italian farmers have more sun, while British farmers typically resort to heated greenhouses to make their tomatoes grow.

Frank Brenmuhl, the chairman of Dairy Farmers of New Zealand, said that fundamental differences in production save energy. “Our cows walk to their food,” said Brenmuhl. “And in the U.K., and in many other systems where they are running on feed lot systems, the food is brought to the animals.”

Since farmers in New Zealand don’t need to grow or transport feed, their meat and dairy products are produced with substantially less energy.

Even transport costs can work against “buying local.” New Zealand is half a world away from the American grocery stories selling its kiwi fruits and lamb chops. But those products are shipped in large cargo ships, which in many cases are more energy efficient per item than trucks.

The local market model as energy saver can break down over shorter distances, since large trucks are more fuel efficient—at least per strawberry—than small trucks.

“Local farmers travel in small pickups and vans. I haven’t seen one pull up in a semi-trailer,” said Rich Pirog, from the Leopold Center for Sustainable Agriculture in Iowa.

Pirog has been researching the benefits of local and regional food systems for years. He said there are a lot of good reasons to buy local, such as supporting local farmers and economies, and getting fresher food. However, he also noted that all food systems have to be accountable for their impacts on the planet.

And that’s where carbon footprint labeling comes in.