Last week I finished up reading Diet for a Hot Planet, and
boy did I learn a LOT. It's a book I'd recommend to anyone interested in
climate change, because the production and distribution of our food is
responsible for 31% or more of global warming effects world-wide. But as
someone who's been a locavore for several years now, it was a book of special
interest.
I became a locavore originally to reduce the fuels used up
in transportation of my foods. It's been suggested to me in the past that this
is misguided at best. This book backs me up to a certain extent, but also shows
that distance travelled is really only part of the emissions equation. One
London study found that production accounted for about half of the emissions
related to the foods studied; transportation produced about one fifth.
Before I delve into some of Ms. Lappé's information, let me
point out that everything I'm about to write here applies to whole foods. I’m not talking about the
evils of packaging, or junk food or fast food. To consider the impact of these
issues, you'd need to add a whole other layer of bad, bad, bad.
As a matter of fact, I'm not even going to start with meat.
Let's talk about conventionally farmed vegetables and fruits. The best-known
difference between conventional and organic produce is the use of pesticides and fertilizers. What you
may not know is that, while both are made from
petroleum, they also use a large
quantity of energy – in the form of fossil fuels – in production. In the U.S.
it's made using natural gas; in China, coal.
I think most of us also know that soil is poorer with the
use of chemical fertilizers and pesticides. Healthy soil serves as a carbon
sink, absorbing carbon and storing it. In unhealthy soil, stored carbon is
released as carbon dioxide.
Additionally, chemical fertilizers break down and release
nitrous oxide, a greenhouse gas with the potential to produce 296 times the
global warming as the same amount of carbon dioxide. Nitrous oxide is the
third-most significant greenhouse gas (measured in carbon dioxide equivalence).
At 7.9% of all total emissions (again, by equivalence), it's not the biggest
piece of the pie by a long shot – but it's still an important part of the
puzzle.
Next, transportation.
This is where a locavore focuses their energy. As mentioned earlier, it's
likely that this is an important consideration in choosing "cool
foods," but it's not the biggest. As always when considering food miles,
you'll want to look at all the layers inherent in production – as the author
puts it, "the food's inputs – not just the distance from the field to the
plate." Fertilizer from far-flung parts of the world, feed for the animals
that produced your meat and dairy products. And if it's a processed food,
multiply that by each ingredient.
It's also worth noting that food is probably travelling
further than you knew. In some places you will see an "average
figure" of 1,500 miles that food travels – but that's related to one very
limited study of a selection of foods travelling within the United States to the Chicago Terminal Market only. Ms.
Lappé's best guess is that "the average food miles for typical food consumed in the United
States is most likely significantly higher." (Emphasis hers.) In fact, a
California study she cites elsewhere in the book found that emissions were 45
times greater for imports than for local, and up to five hundred times greater if travelling by air freight.
Finally, we can cover livestock.
Livestock production in its current form creates a staggering 18 percent of
greenhouse gas emissions globally. As a locavore I've eaten a lot of grass-fed beef
and local milk, but the truth is, ruminants produce loads of methane no matter
how they are raised. Methane is the second-most significant greenhouse gas, 23
times as powerful as carbon dioxide but mercifully less prevalent. It's the
same "natural gas" that energy companies are drilling into shale for,
which is why I once joked that we should raise cows to produce methane instead
of milk – by volume, they certainly make more of the gas! It's almost 10:1.
If you're eating conventional meat, though, you've got more
than ruminant burps to worry about. The same layering effect mentioned above
applies to your meat, and it's a real doozy. Globally, half of all corn and 90%
of all soy harvested is fed to animals. Two-thirds of all the agricultural land
in production is used for raising meat. Half of all energy use related to
agriculture goes to raising animal feed. It takes 16 pounds of soy and corn to
raise one pound of feed-lot beef. (Please note that soy and corn, unlike grass,
could be eaten by people directly, and much more efficiently.) Most of that
corn and soy is raised conventionally, with all the related fertilizer,
tilling, etc.
Another issue with conventional meat is the waste. Animals
in Confined Animal Feeding Operations (CAFOs) produce so much waste in so
little space that in many cases it is stored in what is euphemistically termed
"lagoons." Setting aside the risk of weather-related overflow (ew), manure
lagoons release methane and carbon dioxide directly into the atmosphere, and
not a lot of the stuff gets used as fertilizer or in any other productive
function.
Alarming as a lot of this information is, I experience it as
empowering. It’s information that I can use moving forward to make
more-knowledgeable choices when I set the table for dinner. I've learned so
much from reading this book, and truthfully, I expect that I may read it
multiple times.
You should definitely pick it up to at least leaf through.
Happy eating!
