The new Scientific American blog Science Sushi dispels some myths about large-scale organic agriculture. Here's one example:
Some people believe that by not using manufactured chemicals or genetically modified organisms, organic farming produces more nutritious food. However, science simply cannot find any evidence that organic foods are in any way healthier than non-organic ones – and scientists have been comparing the two for over 50 years.
Better for the environment does not necessarily mean better for you (or for the climate). Not that the environmental benefits are clear either:
Yes, organic farming practices use less synthetic pesticides which have been found to be ecologically damaging. But factory organic farms use their own barrage of chemicals that are still ecologically damaging, and refuse to endorse technologies that might reduce or eliminate the use of these all together.
It's worth a read.
Tuesday, July 26, 2011
Organic vs. conventional agriculture
Thursday, July 21, 2011
Climate impact of different foods
Earlier this week, the Environmental Working Group, a research and lobby group in DC, released a report on the “environment” and "health" impact of different foods. It found that lamb is the worst offender, followed by grain-fed beef, pork, cheese and farmed salmon.
The report was brought to my attention by a writer at the Huffington Post, who subsequently published this story which includes thoughts on the report a number of outside experts on the issue. I commented on the climate impacts of feed production and the logic of farming top-of-the-food chain fish like salmon, both issues that have been discussed frequently here at Maribo.
Here's a more complete list of my thoughts upon examining the short report:
1. “Environmental” impact or “health” impact can be very different than “climate” impact. For example, I’d expect lamb to be much lower on a list based purely on greenhouse gas emissions (i.e. per gram of food produced). I can't comment on "health" impacts as it is not my area of expertise.
2. What I call the “land use cascade” is potentially the largest contributor of greenhouse gas emissions from food production, but also the hardest to calculate. That’s why GHG emissions from dairy relative to beef cattle tend to be overestimated (more methane from dairy cattle, more land required to grow feed for beef than dairy products). It’s also why any study like this should have large positively skewed error bars.
3. All meat is not created equal in terms of greenhouse gases. Grain-fed beef is far less efficient than pork, which is again far less efficient than poultry.
4. If your food choices are motivated purely by concern about greenhouse gas emissions, eating less grain-fed beef is more important than eating locally.
5. Historically-speaking, we are just starting to develop industrial-scale farming of fish, as discussed in the recent Time cover story. Farming the ocean is, in a sense, thousands of years behind farming on land. Right now, many of the choices we are making are, as I put bluntly in the Huffington Post story, “stupid”. Cattle are logical choice for farm animals. They eat grass, so they are only one step away from the sun. Salmon are much higher up the food chain. That’s why many of us say farming salmon is like farming wolves or tigers – you need the whole ecosystem to support the one salmon.
Monday, July 11, 2011
Farming the sea
Especially troubling, many of the most popular farmed species are carnivores, meaning they need to be fed at least partly with other fish. By one count, about 2 lb. of wild fish ground up to make fish meal is needed on average to produce 1 lb. of farmed fish, which leaves the ocean at a net loss.
I've written about this before: A substantial proportion of the wild harvest is used to maintain marine aquaculture of carnivorous species like salmon. It is wildly inefficient, the marine equivalent of farming wolves rather than herbivorous cattle. This is why many experts conclude that the future for pescetarians is probably the blander, lower-on-the-food-chain species like tilapia and catfish.
In coverage of aquaculture, we tend to focus on the sexier and scarier subjects: pollution from farms, genes mixing with the wild population, PCBs in farmed salmon, etc. Certainily, no doubt, these are all serious concerns (except perhaps the PCBs). But the feed-to-fish ratio is the very core of the matter; if you get less fish protein out than you put in, aquaculture doesn't make a heck of a lot of sense.
Walsh gets to this central dilemma in the second half of the article:
When producers began raising fish intensively, they picked species that people like to eat: salmon and sea bass. But those species are high on the food chain, and raising them on a farm is a bit like trying to domesticate tigers. [ed - nice. I always say wolves] The aquaculture industry has gotten better at replacing fish meal with plant-based feed, but not fast enough. You're not feeding the world sustainably if you need to remove the base of the marine food chain to do it.
The solution that many propose is expanding the use of plant-based products in fish food. That brings it's own complications. For one, salmon certainly didn't evolve eating soymeal, cornmeal or wheat, so shifting to a majority plant-based diet will likely involve further genetic engineering, which has supporters and detractors.
And second, feeding plant products to fish would add another player in the struggle for the world's productive croplands.
Forget food vs. feed. Or food vs. fuel. In the future, it will be a battle of the 4 Fs: food vs. feed vs. fuel vs. fish.
Wednesday, February 25, 2009
Fuelling the future
In the latest issue of Momentum, a new magazine out of the University of Minnesota, I argue that "our cars aren't alone in needing a new diet". Here's the opening:
It’s been a tough couple of years for the public relations staff in the biofuels industry.
The production of biofuels from crops like corn has been blamed for everything from driving up global food prices and deforestation in the Amazon to depleting oxygen in the Gulf of Mexico (not to mention raising the price of tequila).
Even the basic purpose of today’s commercial biofuels production has been called into question.
A study by researchers at the University of Minnesota, published last year in the journal Science, found that if previously undeveloped landscapes are cleared for biofuels production, then those biofuels emit more greenhouse gases than gasoline and diesel. Policymakers and the public are now asking if it’s efficient or ethical to use croplands to feed machines rather than people.
There’s one obvious place to look for an answer. In North America, we have been feeding the majority of our crops to machines for decades. These elaborate, protein-producing devices are best known by their common names: cows, pigs and chickens...
Click here for the full article. Or continue after the jump.Eating animals is hardly new. Our nomadic hunter-gatherer ancestors relied on meat for a large proportion of their protein intake. But the advent of agriculture and rise in population after the end of the last ice age led humans to settle in villages and shift to a more energy-efficient, grain-based diet. Over time, meat would be reserved for those who could afford the land and workforce required to raise animals.
Diets in the developed world changed again with the discovery of fossil fuels, especially oil. This cheap source of energy allowed us to produce nitrogen fertilizers, transform crop genetics, fuel agricultural machinery and transport agricultural products around the world. Buoyed by high crop yields and newfound agricultural wealth, we began feeding large quantities of grain and oilseeds to our farm animals.
Today, the average American eats as much as 275 pounds of meat each year, up from 197 pounds in the early 1960s.
Feeding the literally billions of cattle, poultry and pigs now requires a large proportion of the world’s—and mainly America’s—croplands. More than two-thirds of the American corn, soybean, sorghum, barley and oats harvest is used to produce animal feed. That’s more than two-thirds of the fuel used to operate machinery, more than two-thirds of the agricultural chemical use and subsequent water pollution, and more than two-thirds of greenhouse gas emissions from croplands.
In the coming decades, the demand for both animal feed and transportation fuels is expected to rise sharply as Asia and the developing world become wealthier. According to the Food and Agriculture Organization of the United Nations, per capita meat consumption in China has doubled since 1990, and it could double again.
Can our agricultural system meet this increasing demand while also reducing greenhouse gas emissions, tropical deforestation and water pollution? The solution may be switching to more efficient machines.
Like the cars we drive, the animals we eat have wide-ranging efficiencies. Beef cattle are the SUVs of animal agriculture. Renowned energy expert Vaclav Smil calculated that the U.S. agricultural system uses 32 kilograms of feed to produce 1 kilogram of edible beef. Poultry is the fuel-efficient compact of the animal world, with around one-eighth the feed ratio of beef.
The good news is that Americans have been slowly shifting their diets from beef toward more efficient forms of food production. Since the 1970s, per capita beef consumption has decreased 20 percent, while per capita poultry consumption increased by 40 percent. And more and more Americans are forsaking beef or all meat out of health concerns.
A more aggressive move toward poultry, dairy and vegetable-based diets could greatly decrease the land, energy and fertilizer needed to feed the population. In turn, this change would decrease direct greenhouse gas emissions from food cultivation and nutrient pollution to waterways. My own research indicates that reducing beef consumption in American diets would also reduce nitrogen pollution in the Mississippi River and shrink the dead zone in the Gulf of Mexico.
Changing diets would also free up productive croplands for cultivating second-generation biofuels based on unfertilized grains, oil crops or grasses. This newly available land would help eliminate concerns that diverting productive croplands to biofuels cultivation causes the clearing of native vegetation and the release of stored carbon elsewhere in the world.
In a carbon-constrained world, food efficiency may be just as important as fuel efficiency.
Sunday, November 30, 2008
Farming the oceans
An NY Times article a couple weeks back included this snapshot of global fisheries decline, based on data compiled by the experts here at the UBC Sea Around Us Project. The image tells the story of the article, a story not repeated often enough. Without a drastic change in management, we are nearing the end of the wild harvest in fish.
The world is in the middle of phase transition from wild harvest to farming, similar to what happened with land animals. The depletion of the natural resource itself is driven in part by the rapid transition to an energy-intensive farming industry. Consider the proportion of wild fisheries required to support fish and animal feed:
Nearly one-third of the world’s wild-caught fish are reduced to fish meal and fed to farmed fish and cattle and pigs. Aquaculture alone consumes an estimated 53 percent of the world’s fish meal and 87 percent of its fish oil. (To make matters worse, as much as a quarter of the total wild catch is thrown back — dead — as “bycatch.”)
A substantial proportion of the wild harvest is used to maintain marine aquaculture of carnivorous species like salmon. It is wildly inefficient, the marine equivalent of farming wolves rather than herbivorous cattle. This is why many experts conclude that the future for pescetarians is probably the blander, lower-on-the-food-chain species like tilapia and catfish. Continued consumption of popular favourites like tuna and salmon could only happen with drastic improvements in fisheries management.
Marine aquaculture shares many of the shortcomings of industrial animal agriculture. A high input of energy (fish meal, animal feed) is required per unit of food production. Also, a large proportion of the natural resource base (wild-caught fish, agricultural land) must be used to produce the inputs. Finally, research concludes that shifting towards less energy-intensive options (lower on the food chain or "closer to the sun", effectively the same statement) would help sustain the natural resource.
Sure, fish did not evolve to eat grain. Then again, neither did cattle.
Friday, November 28, 2008
Climate change's third rail
After a fisheries seminar this morning, someone asked what key issue the research and conservation community was missing. The immediate answer from a senior colleague was meat consumption.
Given how growing feed and raising livestock is responsible for a large proportion of the world's greenhouse gas emissions, it is quite amazing that we don't talk about it more. An article in the Vancouver Sun last month asked a few of us why. Here are some of the explanations:
Dale Marshall, a climate-change policy analyst with the David Suzuki Foundation: "Food is something that's very personal," Marshall said. "I think there may be a reluctance to start talking about people changing what they eat. When you start telling people to sell their car and jump on the bus, that's a little more out there. But when you start talking about diet and what they eat, that becomes even more personal. So that raises some difficulty in organizations not wanting to go there."
Gideon Forman, executive director of the Canadian Association of Physicians for the Environment: "It's a difficult sell. We're a culture that eats a lot of meat. Unlike in Europe, where it's often a side dish, for North Americans, unfortunately, it's the main attraction. So that's a problem. But I agree, eating less meat would be a big step."
Matt Horne, acting director of the B.C. energy solutions program for the Pembina Institute, said by asking people to reduce their meat consumption, you're asking them to make a real change in their lives. And even though the consequences of not making such changes are calamitous, people are still reluctant to make them. By contrast, buying a fuel-efficient car instead of an SUV is simply a different means to the same end, Horne said. You can still get from A to B.
Dennis Cunningham, a project officer with the International Institute for Sustainable Development, suggested it could be a funding issue. He explained that when environmental groups apply to governments or large corporations for money to produce an education program, the funding organization can dictate the priorities such a program should take. And no government wants to risk offending a powerful agriculture lobby by telling people to eat less meat - even if it's good for them.Sarah Cox of the Sierra Club of B.C. tried to conflate eating less meat with encouraging people to eat locally produced food, something the Sierra Club does do. But Donner said they're entirely different things, and that if one were to choose between eating less meat and eating locally produced food as a more effective way to reduce your carbon footprint, there is only one choice: eat less meat.
He believes the real reason green groups are so shy about discussing meat consumption is that there's an image associated with being a vegetarian or vegan they want no part of. "Environmental organizations often and unfairly have this image of vegan or vegetarian hippies," Donner said. "So if they were to come out and say 'We don't want you to eat meat,' it might reinforce that image and not win over the people they want to win over."
Is meat consumption the third rail of climate change mitigation?
Saturday, November 15, 2008
I'll have the corn, with a side of corn
It is no secret that corn is a major ingredient in animal feed, food oils, and a wide range of food products. A new paper shows that most fast food can in fact be chemically traced back to fertilized feed corn.
The idea behind the paper is relatively straightforward. The authors use the breakdown of carbon and nitrogen isotopes in a variety of fast food - burgers, chicken patties, french fries, etc. - to trace the ingredients and feed back to their source. The only thing missing from this fascinating study is an analysis of the drinks. Whether a cola or "iced tea", the drinks available at most fast food restaurants all have the same two main ingredients: water and high-fructose corn syrup.
The analysis works because of some well-documented patterns in the distribution of carbon and nitrogen isotopes. Corn has a predictably low concentration of carbon-13, because of a strong bias against this "heavier" isotope of carbon during photosynthesis. So much so that if you measure the relative proportion of the carbon-12, the more common isotope, and carbon-13 in the tissue of one of us corn-fed North Americans, you'll find much less carbon-13 than you would in the tissue of a more rice-fed Asian person [and definitely less than in the tissue of a hunter-gatherer from the last ice age]. The basic chemistry shows that North Americans are built from corn.
Nitrogen isotopes also come in handy. They can be used to determine whether chemical fertilizers were used in raising the crops that were fed to the animals or used to create the french fry oil. Fertilizer nitrogen tends to include less of the nitrogen-15 than naturally derived soil nitrogen, because the processes that make nitrogen available in the soil bias against the heavier isotope. So by combining the nitrogen and carbon isotope results, the authors are able to trace fast food items back to their origin:
From the entire sample set of beef and chicken, only 12 servings of beef had 13C < 21‰; for these animals only was a food source other than corn possible. We observed remarkably invariant values of 15N in both beef and chicken, reflecting uniform confinement and exposure to heavily fertilized feed for all animals. The 13C value of fries differed significantly among restaurants indicating that the chains used different protocols for deep-frying: Wendy’s clearly used only corn oil, whereas McDonald’s and Burger King favored other vegetable oils; this differed from ingredient reports
The conclusion is an indictment of North American fast food:
Fast food corporations, although they constitute more than half the restaurants in the U.S. and sell more than 1 hundred billion dollars of food each year (18), oppose regulation of ingredient reporting‡. Ingredients matter for many reasons: U.S. corn agriculture has been criticized as environmentally unsustainable
(19) and conspicuously subsidized (20). Of 160 food products we purchased at Wendy’s throughout the United States, not 1 item could be traced back to a noncorn source. Our work also identified corn feed as the overwhelming source of food for tissue growth, hence for beef and chicken meat, at fast food restaurants. We note that this study did not include an examination of beverages served, which are dominantly sweetened
with high fructose corn syrup (21). In 2002, the European Union adopted Regulation 178 (11) requiring suppliers to trace the origin of materials used for production. At this time in the United States, such tracing is voluntary and seldom-invoked. Our work highlights the absence of adequate consumer information necessary to facilitate an ongoing evaluation of the American diet.
Tuesday, May 13, 2008
King Corn and the food crisis
Last weekend, I was asked to answer a few questions after a local screening the film "King Corn", an offbeat documentary by a couple young college grads who decided to move to Iowa and try growing the crop that fuels us all. The audience questions centered around the usual public fears about food. Is all corn GMO? What animals can eat corn? What else are they fed? Where can I learn more? And, my favourite, is the "glucose-frutcose" listed on my bottle of Arizona Iced Tea made from corn?
I'm not an expert on all those subjects - and I admitted as much at the screening. I can say that the answer to that last one - yes - got me thinking more about the uses of our crops and the causes of the world food crisis.
Frankly, any ingredient that you do not recognize on the label of a processed food or beverage is probably made from corn. Xathan gum? A fermented sugar made from corn. Lecithin? Made from corn. Vanilla extract? Vanilla and corn syrup. Malt extract? Often made from corn, not barley. Dextrin? As Michael Pollan would say, corn, corn, corn.
Corn is so ubiquitous in our food today, that it is natural to assume that food is the reason we grow so much corn. But all those food additives and sugars made from corn, including the bane of nutritionists and foodies, high-fructose corn syrup (I highly recommend the scene in King Corn where the protagonists try to make some in their kitchen), still only make up a small fraction of the corn crop. The US don't produce corn to make high-fructose corn syrup, it produces high-fructose corn syrup because it has developed an agricultural system that profits on producing large volumes of corn anyway. The majority of that corn, until very recently, was bring to animals, largely beef cattle.
The graph to the left shows the end use of US corn over the past six years (all data that follows is from the Foreign Agriculture Service and the Economic Research Service of the USDA). The big pink block in the middle is domestic feed use (~60%, down to 47% last year). The top category is exports, most of which is also used as feed (19%). The dreaded high-fructose corn syrup has been around 7% (5% last year) of the corn crop, glucose / dextrose around 2-3%, beverage alcohol (yep, there's corn in that Bud Light) around 1-2%. Cereals and other foods? 2%.
The one area of growth (in blue) is fuel alcohol, or ethanol. Last year, 24% of all US corn production (29% of non-export corn) was used for ethanol. The percent breakdown of corn use changed the last few years as a result of the ethanol surge. But the other uses of corn, in terms of raw numbers did not. Exports and feed use were relatively flat (an assumption made in our paper on the subject). The US simply grew more corn to produce ethanol. As many have been arguing, that is why US production of corn-based ethanol has not played a role in the global food crisis. No harm, no foul, right?
Tempting, but there are two holes in that argument.
First, the extra corn for ethanol has to be planted on productive croplands, lands with the right soils, and most of that land is being used. In 2007, soybean planting - the other major feed crop grown in the midwest US - went down 16% in the US to make space for more corn. Soybean exports and use remained the same, but the ending stocks were down 72%. In other words, we've been cleaning out the cupboards.
Soy planting is back up to 2006 levels this year, as prices rose and farmer rotate those fields full of corn back to soy, as is common practice. If the US to keep up ethanol production, soy planting will probably drop again the following year, or corn exports will go down. In other words, if corn ethanol production is to continue or increase, the US is most likely going to have to i) export less corn, ii) export less soybean, or iii) produce less domestic feed.
Complicated business - and potentially very profitable business. If you are a speculative investor with a fast computer, there's a lot of money to be made betting on crop production. The world relies on a very small number of staple crops for food and feed: corn, soybeans, wheat, rice, and other regional crops like cassava. The planted area, production and price of one can affects the others. The ethanol surge in the US paved the way for more speculative investment in commodities, which has helped drive up prices.
Second, the US is the world's largest producer of corn and soybeans. The demand for both has been rising for years because of rising meat consumption in Asia.
. The US produced 43% of world’s corn in 2007/2008 (right). The US is also responsible for two-thirds of all the global corn exports. If you need to buy some corn, there are few other places to shop. Last year, the amount of corn used for ethanol in the US in 2007/2008 is greater than the domestic corn production of every other country in the world, save China. That's taking a lot of potential grain off the market. Now, yes, exports remained steady last year. But to meet the growing demand - feed consumption in China alone is rising a few percent a year - exports should be growing. The signs point to, at best, exports remaining constant, or at worst, exports decreasing.
There are a lot of causes of the current food price crisis - I recommend the FAO's website for information. Many have called it a perfect storm of oil prices, ethanol production, rising meat consumption, drought, price speculation, rising population. The corn-based ethanol surge in the US is not the sole cause, by any means, but it has played a role.
The global food system may have been a dam that was ready to break. The growing population and growing demand for animal feed had filled the reservoir up to capacity. The US ethanol policy helped crack some holes in the concrete.
Sunday, May 11, 2008
Shifting diets vs. eating local
I finally had the chance to read this terrific paper by Christopher Weber and Scott Matthews of Carnegie Mellon that compares greenhouse gas emissions from the production different types of food and the delivery of that food to your plate. As was reported by some news agencies and blogs, Weber and Matthews conclude that transportation represents only 11% - on average, it depends on the food – of the total life-cycle GHG emissions of U.S. food (there’s little reason to expect a dramatically different result in Canada).
The take home message is shifting your diet will do far more to reduce greenhouse gas emissions than buying local. From the paper:
The results of this analysis show that for the average American household, “buying local” could achieve, at maximum, around a 4-5% reduction in GHG emissions due to large sources of both CO2 and non-CO2 emissions in the production of food. Shifting less than 1 day per week’s (i.e., 1/7 of total calories) consumption of red meat and/or dairy to other protein sources or a vegetable-based diet could have the same climate impact as buying all household food from local providers.
The authors did some simple calculations to demonstrate this point:
To put these figures into perspective, driving a 25 mi/gal (9.4 L/100 km) automobile 12 000 miles/yr (19 000 km/yr) produces around 4.4 t CO2/ yr. Expressed in this manner, a totally “localized” diet reduces GHG emissions per household equivalent to 1000 miles/yr
(1600 km/yr) driven, while shifting just one day per week’s calories from red meat and dairy to chicken/fish/eggs or a vegetable-based diet reduces GHG emissions equivalent to 760 miles/yr (1230 km/yr) or 1160 miles/yr (1860 km/yr), respectively. Shifting totally away from red meat and dairy toward chicken/fish/eggs or a vegetable-based diet reduces GHG emissions equivalent to 5340 mi/yr (8590 km/yr) or 8100 mi/yr (13 000 km/yr), respectively.
It is important to note that macro-scale GHG “accounting” studies always come with a number of caveats. The calculations or model requires a number of simplifying assumptions and often some more complicated factors are often excluded. The two central limitations to this particular study appear to be the simple treatment of direct GHG emissions from animal and crop production (i.e. N2O from manure, fertilizer and the animals themselves) and the exclusion of land use impacts and the “land use cascade” (i.e. carbon released from directly or indirectly transforming land for crop or animal production). Improving those components of their mode should increase the share of GHG emissions from food production and the relative GHG emissions from red meat production. In other words, that provides even more support for the conclusion that eating less beef is one of the best ways to reduce personal greenhouse gas emissions.
Tuesday, April 15, 2008
Food prices and the use of corn
The rise in food prices is finally garnering serious attention from the media and from world governments. The latest NY Times piece has this precious quote from Senator Charles Grassley of Iowa:
“You make ethanol out of corn,” he said. “I bet if I set a bushel of corn in front of any of those delegates, not one of them would eat it.”
Never mind the fact that a bushel is more than 25 kg of corn, Sen. Grassley (in claiming that the diversion of corn for ethanol is not affecting food prices) rather accidentally describes the exact problem. We don't eat the corn. In the U.S., the majority of the subsidized crops corn and soybeans (~75% in our most recent look at the economic data) are used for animal feed. And it is the rise in demand for meat, together with biofuel demand, high oil prices and droughts overseas, that is driving up food prices.
Wednesday, April 09, 2008
Growing ethanol on conservation lands
One of the assumptions in our recent paper on the impact of increasing corn ethanol production on the Gulf of Mexico Dead Zone is that farmers could start to plant crops on land enrolled in a federal conservation program.
The latest data shows that may be happening. The area of U.S. croplands enrolled in the federal Conservation Reserve Program decreased from by 2.12 million acres since July of last year (using February data), a drop of 6%. The NY Times reports that the drop was caused by high commodity prices, driven in part by the ethanol boom.
Farmers sign a ten-year contract when entering land in the CRP. As it stands, that land cannot be returned to cultivation until the contract expires. It is worth remembering that, despite the headlines and echoing blog posts, the area of CRP lands had been increasing for the past ten year, reaching an all-time high last year. This recent drop does not negate those changes. So the real question is what happens to the 9.5 million acres of land for which the contracts expire in the next three years.
Monday, March 10, 2008
Corn ethanol production will worsen the Dead Zone
A new paper by my colleague Chris Kucharik and I looks at the new US Energy Policy, will calls for growing more corn to produce ethanol, will affect the "Dead Zone" in the Gulf of Mexico. For a quick summary, see Reuters, the CBC or AFP (or my 15 Minuten ruhm on German ARD). Wired and Scientific American go into more detail.
The Mississippi dumps a massive amount of nitrogen, largely in the form of the soluble ion nitrate, into the Gulf each spring. It promotes the growth of a lot of algae, which eventually sinks to the bottom and decomposes. This consumes much of the oxygen in the bottom waters, making life tough for bottom-dwelling fish and creatures like shrimp. The Dead Zone has reached over 20,000 km2 in recent years.
The primary source of all that nitrogen is fertilizer applied to corn grown in the Midwest and Central US. Reducing the Dead Zone to less than 5000 km2 in size, as is suggested in US policy, will require up to a 55% decrease in nitrogen levels in the Mississippi.
The new US Energy Policy calls for 36 billion gallons of renewable fuels by the year 2022. Of that, 15 billion can be produced from corn starch. Our study found meeting those would cause a 10-34% increase in nitrogen loading to the Gulf of Mexico.
Meeting the hypoxia reduction goal was already a difficult challenge. If the US pursues this biofuels strategy, it will be impossible to shrink the Dead Zone without radically changing the US food production system. The one option would be to dramatically reduce the non-ethanol uses of corn. Since the majority of corn grain is used as animal feed, a trade-off between using corn to fuel animals and using corn to fuel cars could emerge.
Saturday, January 26, 2008
Greenhouse gases, meat consumption and the Amazon
The Sunday NY Times has a good story on the global environmental burden of meat production, an issue that's been covered here on and off over the past couple years. Meat production, particularly beef, is responsible for a large proportion of the world's greenhouse gas emissions due to the energy required to grow animal feed, the clearing of land for feed crops, N2O emissions from fertilizer application and both N2O and CH4 emissions from the animals themselves. The graph at right shows the consistent rise in per capita consumption in the Americas and Asia over the past 45 years. Meat production and consumption is expected to continue to rise due to rising demand in China and other parts of Asia.
The demand for animal feed, coupled the demand for biofuels, is being felt most of all in the Amazon, the one large area of "unused" and potentially productive farmland left on the planet. The rate of Amazonian deforestation increased in the last few months, and may increase further in the rainy months to come, when most illegal cutting usually occurs.
Sunday, September 23, 2007
Greenhouse gases and meat production
There’s a lot of chatter today about the role of meat consumption in climate change. The UN entered the fray last year with a report estimating that livestock are responsible for 18% of the world’s greenhouse gas (GHG) emissions, more than the total for all forms of transportation. It is, at first glance, hard to accept. But the UN estimate is, if anything, rather conservative.
Read more at Celsias
Tuesday, July 31, 2007
A good tool for calculating your emissions
If you're looking for a carbon calculator, try this one put together by the Berkeley Institute for the Environment (thanks to Atmoz for the tip). Unlike most of the calculators out there, it does more than multiply the # of miles your drive and fly by some factors and spit out in answer. It considers several forms of transport, home heating and electricity, the food you eat and even how you spend the rest of your money, then compares your results to the American and world average.
My estimated personal emissions in the past year were nothing to be proud of, thanks almost entirely to twice flying halfway around the planet and back. Coming back always gets you. I take little solace in the fact that my emissions total was still less than the average American, even in the transport category. Instead, I take two lessons: a) studying the effect of climate change on the environment often contributes to the problem, no surprise there, and b) transportation is so stunningly inefficient in this country that someone can circle the planet twice and still produce less greenhouse gas emissions than the average American.
As for the calculator, my only beef is the, er, beef. Emissions from consuming red meat and consuming dairy are similar (per $ spent), so a lacto-ovo vegetarian may end up with similar or higher food-related emissions than a regular at Mel's Char Palace. From all the research we've done, dairy is much more efficient, in terms of the grams of feed required to create a gram of food, for the simple reason that milking doesn't kill a cow. This point that seems to be missed a lot; the source of greenhouse gas emissions from meat is not the animal itself, but all the energy that went into growing the crops that are then fed to the animal.
Friday, April 20, 2007
The truth on greenhouse gases and meat consumption
Last week, Washington Post George Will wrote a sadly uniformed column attacking the public campaigns to reduce greenhouse gas emissions. It drew the usual array of responses and partisan blustering (left, right, ridiculous).
At heart was Time Magazine’s “Global Warming Survival Guide” which featured advice like 51 Tips on Saving the Environment, never mind that global warming is not merely an environmental problem, and that many of the tips have nothing to do with the environment, rather with improving human health.
Tip #22 -- Skip the Steak – claims that livestock is responsible for around 18% of the world’s greenhouse gas emissions. That’s not a mistake. The number comes from a prominent UN report released last year.
What Time, what George Will and what the vast majority of commentators on this subject get wrong is why livestock is responsible for such a large proportion of the world’s GHG emissions.
Columnists and pundits love to joke about cow farts and manure – producing methane and nitrous oxide, respectively – like they’re in bad Adam Sandler movie. That is an important source of GHG. But, in reality, the majority of the emissions attributable to livestock are not coming out the back end, but coming from all the energy used to grow the grain that is fed to livestock.
The United States alone grows almost half of the world’s corn and soybeans. And more than two-thirds of that production is used to manufacture animal feed. It requires an enormous volume of oil, to produce fertilizer and run farm machinery, and an enormous area of land. In turn, it is responsible in part for a number of ecological problems, like the “Dead Zone” in the Gulf of Mexico.
Will seems to mistakenly stumble upon this point, in the midst of some sarcasm, but :
Ben & Jerry's ice cream might be even more sinister [than a steak]: A gallon of it requires electricity-guzzling refrigeration and four gallons of milk produced by cows that simultaneously produce eight gallons of manure and flatulence with eight gallons of methane. The cows do this while consuming lots of grain and hay, which are cultivated by using tractor fuel, chemical fertilizers, herbicides and insecticides, and transported by fuel-consuming trains and trucks.
The concept is right, the comparison is flat wrong. Producing a gram of dairy protein requires only a fraction of the energy of producing a gram of meat protein, especially beef (for the simple reason you don’t kill the cow every time you milk it).Of the feed produced in the United States, only 12% is devoted to dairy cattle (see here). The rest goes to beef cattle, poultry and pork production. That’s why you often hear claims that we should all eat less meat, but not less dairy.
In essence, this problem is not about meat consumption. It is about devoting a significant proportion of our energy and our land to produce meat. One of the biggest obstacles to reducing greenhouse gas emissions in the future will be diet. We may or may not be exporting democracy to the world, but we certainly are exporting our meat-rich diets. As meat consumption rises in China and other parts of the developing world, the challenge of reducing oil consumption and reducing greenhouse gas emissions will grow. More on that later.
Friday, March 30, 2007
What the record corn crop actually means
U.S. farmers are expected to plant 37 million hectares of corn this spring, the largest area of corn since “the Allies invaded Normandy”. It is a 15% increase from last year, all thanks to the demand for ethanol. At the same time, the planted area of soybeans is expected to be 11% lower than last year.
That’s 90.5 million acres of corn, in American English (sick of getting sent data in pounds, cubic feet per second and acres, I'm a on one-person quest to convert to USDA and the USGS to metric).
The media has been all over this today. The coverage I've seen is largely missing the point.
Corn and soybeans are the two prominent crops in the central U.S. For the past 10-15 years, the “Corn Belt” has really been the “Corn and Soybean Belt”. In 2006, the planted area of corn was 31.9 million ha; of soybeans, 30.6 million hectares. The crops are often grown in rotation – corn on a field one year, soy the next – since the nitrogen-fixing soy helps reduce fertilizer needs on corn (and residual nitrogen from corn helps the soy the next year). Both crops are largely used to generate animal feed, a sizeable chunk of which is exported to Europe and Asia.
We’re not about to discover more fertile farmland in the US. The additional corn to produce ethanol is largely coming two ways:
1. Replacing other crops. Since soybeans and corn are usually grown together, the surge in corn means less soy being grown. That means fewer soy available as feed, both here and overseas.
2. Reducing other uses of corn. The major uses of corn are animal feed, exports (mostly feed), food and now fuel. The domestic animal feed isn’t changing substantially lest we change our diets; the domestic food is a small fraction; the surplus here is coming from exports.
Those headlines about the impending choice between food and fuel? That’s not happening here, at least not yet. Ethanol is being generated in the US via planting more corn (at the expense of soy) and exporting less corn. The result is not less food in the store. It is less grain being sold for feed overseas.
That has market implications and environmental implications overseas(more on the environmental side later). As has been widely reported – the “tortilla effect” in Mexico – the price of corn has been high because the supply is being diverted (from exports for feed) to ethanol. It is important to remember that plenty of other factors affect food and crop prices. People seem to be getting carried away blaming ethanol for everything, like the price of wheat, which is rarely used for feed or to generate ethanol.
As for the US, with a 15% increase in planting of heavily fertilized corn, at the expensive of largely unfertilized soybeans, there may also be a record amount of nitrogen in central US soils this summer. A wet spring means a large hypoxic zone is likely to appear in the northern Gulf of Mexico next summer.
Thursday, March 01, 2007
Organic Inc.
Last week, the grocery store chain Whole Foods has bought out its primary rival Wild Oats. The response, expressed with a palpable taste of “I told you so”, seems to be that the buyout represents the final proof of Whole Food’s transformation from idyllic, local organic food store to corporate behemoth high on money, power, and high fructose corn syrup is now officially complete.
The talk of this transformation as some archetypal, to use a word from 11th grade English class, fall from grace, the way people response when a hometown sports hero signs a free agent contract with another team, is amusing. Wild Oats was not your local health food store. The food is as expensive, and is shipped as insanely (Chilean orange anyone?), as that at Whole Foods. As the article Is Whole Foods Straying From Its Roots? in yesterday’s NY Times points out – if you can get past the self-righteous undertone – Whole Foods is in essence trying to stop the larger, traditional grocery stores from taking some of its market. There’s always a bigger fish in the sea.
It brings us to a question that has divided environmental movement for years. Which is better? Getting the big fish to change or having lots of little fish take over? In other words, do you work with Walmart to become more environmental friendly? Or do you boycott their stores?
There’s no easy answer, not in today's world. I will say this. I’m sad to hear the Wild Oats on Nassau St. in Princeton will be closing. That’s not to say I like shopping there. I simply like the idea that people in town can walk and bike to the grocery store, whatever that store is. The only Whole Foods in the area is on Rte 1 and has no pedestrian or bicycle access. Now that is a crime.
