Summer 2008 Climate Alert
Climate Change & Food Security [ PDF ]
In this Newsletter:
Cutting Food Miles
Earlier this year, celebrity chef Gordon Ramsay made headlines by suggesting that the British government introduce legislation outlawing the use of anything but locally sourced, in-season produce in restaurants. “I don’t want to see asparagus [on the menu] in the middle of December. I don’t want to see strawberries from Kenya in the middle of March. I want to see it home grown,” he said.
Ramsay may be an extreme example, but the concept of
local food – that is, food grown within a small radius, often
about a hundred miles, of where it is consumed – is a growing
trend, popularized by bestselling books like Michael
Pollan’s The Omnivore’s Dilemma and Barbara Kingsolver’s Animal, Vegetable, Miracle.
Not only self-proclaimed
“green” retailers like Whole
Foods, but also discount
supermarkets like Wal-Mart,
are adding local selections to
their inventories and in 2007,
the New Oxford American
Dictionary chose “locavore”
as its word of the year.
From an environmental
standpoint, limiting the distance
that food travels from
the farm to the plate makes
intuitive sense. Enormous
quantities of fossil fuels are
used during transport from
the producer to the consumer,
whether food is trucked
cross-country or flown in
from overseas. Beyond the
direct impact on the climate
of carbon emissions from fuel
combustion, long-distance
transports require more packaging
materials and refrigeration
to preserve the freshness
of the food, consuming additional
energy and resources. According to a study by the
Worldwatch Institute, food typically travels over 1,500
miles from where it is grown before it reaches your table.
The idea, then, is that by seeking out produce with local provenance, now almost as easily available at the grocery store as at the farmers’ market, consumers could drastically reduce their carbon footprint. To make comparison easier, some have advocated calculating “food miles”—the total distance a food item travels from the farm to the grocery store — as a guideline for sustainability.
Of course, the reality is rarely that simple, and a number
of confounding factors make food miles a problematic measurement.
Likely the most damning is the fact that while
food miles provide an estimate of the carbon emissions
caused by long transports, this does not account for differences
in production inputs, which can vary widely depending
on each farm’s scale and practices. That might include
the additional energy needed to heat a greenhouse in an area
where the climate is unsuitable for growing certain fruits or
vegetables, or the chemical fertilizers and pesticides used in
conventional farming. According to one study by researchers
at Carnegie Mellon University, a one-kilogram loaf of
wheat bread produced with conventional farming methods
caused a similar level of carbon dioxide emissions as a loaf
of organic bread produced 420 miles farther away. Here,
the reduction in greenhouse
gas emissions made possible
by using organic rather than
conventional wheat offset, to
a certain extent, the impact of
a longer transport.
Moreover, the exhortation
to “eat local” without differentiating
between types
of food neglects the fact that
some are inherently more
sustainable than others.
According to a 2006 report by the United Nations Food
and Agriculture Organization
(FAO), the livestock sector
generates 18 percent of carbon
dioxide emissions worldwide
(surpassing the transport
sector) and 37 percent of
human-induced methane.
In other words, where total
greenhouse gas emissions are
concerned, vegetables flown
cross-country may in fact be
more sustainable than locally
produced beef.
Becoming more aware of the environmental hazards of long-distance transports is without a doubt a step in the right direction, but it is important not to lose sight of the other, sometimes more pressing aspects of food production that contribute to climate change. In an ideal world, we would all take our bicycles to the farmers’ market and purchase only local, organic, vegan produce; in practice, even Gordon Ramsay’s restaurants serve items like “tropical fruit desserts” and “ravioli of Italian winter squash.” However, any serious effort to combat climate change will require a more careful look at where our food really comes from, and the local food movement is a step in the right direction.
Other Articles in this Newsletter:
Climate Change & Food Security
A Message from the President: Fishes, Loaves and Foresight
The Challenges of Producing Food on a Warming Planet
Reducing Our Food's Impact on Climate Change
Focus: Moving Down the Food Chain
Case Study: Agriculture in Thailand
The Biofuel Debate: Food vs. Energy?