The Story of Nitrogen

I've been reading the Alchemy of Air by Thomas Hager.  It is one of the most interesting books I've read in a long time.  It chronicles the history of nitrogen fertilizer, and Hager does a got job describing the fact that the availability of nitrogen has been the key limiting factor to food and population growth throughout much of man's agricultural history.  He writes:

As a species we long ago passed the natural ability of the planet to support us with food.  Even using the best organic farming practices available, even cutting back our diets to minimal, vegetarian levels, only about four billion of us could live on what the earth and traditional farming supply.  yet we now number more than six billion, and growing, and around the world we are eating more calories on average than people did in Crookes's day [late 1800s].

He describes the problem as follows:

These three elements, carbon, oxygen, and hydrogen, constitute more than 90 percent of our bodies by weight . . . But, the most important element in many ways for humans is the fourth most common in our bodies - and the hardest to find in nature (at least in forms we can use): nitrogen.  It is stitched into every gene in your DNA and is built into every protein.  If you don't get enough nitrogen, you die. . . . the absolute necessity of nitrogen or life leads to a paradox: We are swimming in nitrogen, but we can never get enough.  

The problem is that all the nitrogen in the air is unavailable to humans and to most plants.  It must be "fixed" before it becomes chemically available to us.  

Hager documents the fact that cover crops and manures in the middle ages simply weren't enough to replenish nitrogen in the soil, so there were constant yield declines.  The only answer was to find new land. No wonder colonization was so attractive to European powers.  By accident, farmers found that various forms of nitrogen found in nature could enhance yields, but after depleting guano deposit in Peru and mining the Chilean desert, there still wasn't enough to go around.

It is hard to imagine a greater discovery for the prospects of mankind than the process created by Haber, Bosch, and other German scientists in the early 1900s to "fix" nitrogen from the air.  And yet, it is probably one of the the most under-rated scientific advancements of all times (perhaps because it cause a great deal of damage too by allowing Germany to prolong WWI by converting ammonia into gun powder).  

Indeed, I had a college student try to tell me in a Q&A after a lecture I gave at another University a few weeks ago that nitrogen was not a limiting ingredient for agriculture.  It might be possible for a small farm feeding a small number of people to be somewhat self sufficient in nitrogen (yet even they must get their nitrogen from somewhere). But, it is simply not possible to support urban populations like those in NYC, Boston, London, or Hong Kong by using only the nitrogen available in manure and fixed by currently available cover crops.  

If you're bored over the Christmas break, you could probably find worse things to do than read a little about the history of nitrogen.

FooDS December 2013

The December edition of the Food Demand Survey (FooDS) is now up.

A few observations from the survey:

• Willingness-to-pay (WTP) for chicken products was down in December.  In fact, WTP for chicken breast was at the lowest level since the survey started back in May.
• WTP for steak only declined 4.3%, but was also at the lowest level seen since FooDS started.
• The only meat product to witnessed increased WTP was hamburger.
• Stated concern for all 17 food issues we track fell in December relative to November.  
• This month, consumers heard less in the news about Salmonella and E coli and more about GMOs and farm animal welfare.
• In a ranking of seven food challenges, the largest increase in December was "loosing weight".

As in the past, we added several ad hoc questions.  Given my recent visit to BPI, I was curious to learn more about consumers' perceptions of lean fine textured beef (LFTB), a product that has been called "pink slime" by some media outlets (I should note that these questions were added of my own volition, not at the request of BPI).  We asked "Which of the following do you believe is true or false about lean finely textured ground beef (otherwise known as "pink slime")?"  Here is what we found:

Most consumers correctly indicated that LFTB lowers the price of lean ground beef.  however, they also got quite a few facts wrong, and the results underscore the misconceptions people have about the product, some of which have been fostered by media outlets.  For example, more than half the participants thought LFTB led to illnesses, was used in dog food, and is unsafe to eat.  Only 25.59% thought beef is the only ingredient (so much for the effectiveness of the "beef is beef" campaign), and more than three-quarters disagreed that LFTB improved the taste of beef.  

We also asked a subsequent question, where respondents ranked the desirability of different hypothetical ground beef options that varied by price, LFTB content, fat content, and taste.  Analysis of this data suggests taste is the most important factor but that people were WTP substantive premiums to avoid LFTB.  That said, people also stated a preference for leaner ground beef.  Overall, the results imply that some the consumers' dislike of LFTB can be offset by: 1) better taste, 2) lower price, or 3) some combination of lower fat content and lower price or better taste.   

How surveys can mislead

Beef Magazine recently ran a story about changing consumer attitudes.  The story discussed the results of a nationwide survey which asked the question: "How has your attitude about the following issues changed during the past few years?"  Here is a screenshot showing the results  

So, according to the survey, 29%+35%=64% of consumers are today more concerned about antibiotics than they were a few months ago.  In fact, the figure suggests that more than half of the respondents are more concerned today about antibiotics, hormones, GMOs, animal handling, and farmer values.   

I would submit that these findings are almost entirely a result of the way the question is asked.  Are you more concerned about issue X today?  Well, of course, any reasonable, caring person is today more concerned about X.  Indeed, why would you even be asking me about X unless I should be more concerned?

More generally, drawing inferences from such questions shows the danger of taking a "snapshot" as the truth.  To illustrate, let's compare how the above snapshot looks compared to the trends that come up in the Food Demand Survey (FooDS) I've been conducting for eight months.  

In that survey, I ask over 1,000 consumers each month a question, "How concerned are you that the following pose a health hazard in the food that you eat in the next two weeks?"  where the five-point response scale ranges from "very unconcerned" to "very concerned".  

I pulled out responses to the four issues that most closely match the survey above and plotted the change over time (I created an index where the responses in each month are relative to the response back in May which was set equal to 100).  If people are generally more concerned about these issues today compared to six months ago, it isn't obvious to me from the graph below.

So, a word of caution: you can't take every survey result at face value.  These sorts of comparisons show exactly why our Food Demand Survey is valuable: it replaces a snapshot with a trend. 

Nice Profile of Keith Coble

A couple months ago a  blogger at Delta Farm Press ran a piece about my friend and co-author Keith Coble.

It was no surprise, therefore, when earlier this year Senator Thad Cochran, R-Miss., asked Keith to come to Washington as chief economist for the minority staff of the Senate Committee on Agriculture, Nutrition, and Forestry, which Cochran serves as ranking minority member.  Keith continues a line of MSU ag economists, including the university’s president Mark Keenum, who have participated in the process. 

“This government shutdown has been déjà vu all over again,” said Keith, back at MSU to speak at the annual meeting of the Mississippi Agricultural Economics Association. “I was in Washington for five years before I came to MSU, including the 1995 government shutdown, when I was deemed ‘non-essential’ and told to go home and do no work. During this shutdown, I got a phone call telling me I’m essential — an upgrade from the last time — but to stay home until discussions started again.”

Keith astutely points out of the key challenges with developing  a new farm bill:

And this time around, “There have been a lot more groups, and a lot different groups at the table that weren’t players 10 years ago or 20 years ago — environmental interests, food interests, etc. They’re all players now, and they do matter; it’s a very different dynamic.

The Hidden Cost of Cheap Food

The "food movement" has a long and varied history, but it seems to me that much of the force behind the modern calls for action came from writings during the early to mid-2000s (think Supersize Me or Fast Food Nation or Omnivore's Dilemma or Food Politics, which ultimately lead to more recent things like Food Inc and Salt Sugar Fat and Pandora's Lunchbox).   

The interesting thing about this time period is that food commodity prices were historically very low.  As a result, a common mantra developed that goes something like the following.  Food is too cheap.  This cheap food masks costs to health and the environment.  These masked costs represent externalities, and economics tells us that externalities justify government action like food taxes, subsidies, etc.  This line of thinking reached such a level that the CDC and the Institute of Medicine of the National Academies has held a couple meetings on the issue (I participated in one of those; more on that in a moment).   

There are two problems with this like of reasoning.  First, in the US, we witnessed extraordinarily run-ups in commodity prices in 2008 and again in 2011.  Worldwide, food prices are higher today in real terms than has been the case for almost 40 years (e.g., see this UN FAO graph).  One might argue that certain types of foods are "too cheap" but to broadly make such a claim is no longer consistent with the facts.  Second, I think outside circles of trained economists, there is often a deep misunderstanding of the nature of externalities, and even within economic circles a lack of critical thinking about the ability of taxes/subsidies to solve externality problems.  

This second point was the focus of an invited talk that I gave to the Northeastern Agricultural and Resource Economics Association this summer in Ithaca, NY.  That address has been published in the association's journal, the Agricultural and Resource Economics Review.  The paper is now available online.  

Here is the abstract:

Social critics have taken aim at modern production agriculture using a common theme: many food, health, and environmental problems are explained by corporate farms, agribusinesses, and fast-food restaurants failing to account for the full costs of their actions. How accurate is this diagnosis? How feasible is the assumption that these externalities are most effectively mitigated via Pigovian taxes and subsidies? Drawing on my experiences at a National Institute of Medicine meeting on the subject, I seek to clarify the definition and nature of externalities and discuss situations in which public policy is most and least effective in efficiently making "hidden” costs of food visible.

A few snippets:

One of the striking observations that emerged from the conference was
the wide disconnect between the views held by participating economists
and noneconomists about the nature and role of externalities. Among many of the noneconomists, it seemed that any “bad” outcome that resulted from food production and consumption—heart attacks, obesity, the low pay of slaughterhouse workers, soil run-off, animal welfare problems, climate change— was evidence of an externality that required regulation, typically in the form of some sort of tax. I also learned in the process that some of my views about externalities were perhaps a bit unorthodox relative to those of other economists.

and

Clearly, the case for regulating externalities is more complicated than first
meets the eye. Indeed, as the preceding examples illustrate, one is apt to
see externalities everywhere. The sheer abundance of examples that fit the definition of “externality” coupled with our unwillingness to tax them all
away is suggestive. As Coase put it, “The ubiquitous nature of ‘externalities’ suggests to me that there is a prima facie case against intervention”

and I start the conclusions with the following:

This essay arose from my failed attempts to explain externalities to
noneconomists and my desire to challenge fellow economists to think more seriously about the real-world implications of policy advice derived from simple textbook models. In popular writing about food and agriculture, there seems to be a lack of appreciation for the types of externalities that reduce welfare and of the difficulty associated with crafting corrective actions that actually increase the size of the pie. Moreover, the concept of externality is often used to advance a particular cause or point of view. There is a lot of talk about the “hidden costs” of our modern food production system. What about the “hidden benefits?” Failing even to mention, let alone seriously address, that question suggests that one is not willing to think seriously about externalities as anything more than academic-sounding justifications designed to garner enough power and support to enact a faction’s preferred policy.

I learned a lot writing the essay, I hope readers might learn something too.