The Entropy of a Carrot
Feel your forehead. You’re warm to the touch. You glow. In the infrared, you literally, physically, glow… not entirely like, but also not entirely unlike, the star at the center of our solar system that fuels over 99% of the life on our wet, rocky home. For that life to exist, energy must flow. Nearly the entirety of all lifeforms on earth are, at their core, channels for the flow of solar energy. Sourced from the heavens, it’s funnelled into and out of cells, across ecosystems, and piped through their untold relations, until its light ultimately returns to space once more. That said, all those exchanges leaves that light less energetic than it was at its outset, as it dutifully obeys those most fundamental laws of conservation and chaos; the laws of thermodynamics. As the 18th century physicist Rudolf Clausius commented of those laws as he was developing them: “The energy of the universe is constant; the entropy of the universe tends to a maximum.”
Entropy is a statistical measure of disorder within any thermodynamic system. It simply means that as time progresses and change unfolds, there will usually be more ways for things (atoms, energy) to become messily arranged than neatly arranged. That entropy should forever increase serves as an inviolable rule of existence. Collections of matter and energy spread out, corrupt, and diffuse over time. But by simply looking around at the ordered, living bodies that fill our world, common sense seems to tell us there’s something else at play. Living systems, be they person or plant, hominid or carota, must compensate for their embodied order by tapping into readily available sources of low entropy and dissipating the energy used in growth, maintenance, and reproduction as high entropy waste products, both material and luminous. To James Lovelock, founder of the Gaia hypotheses, earth as seen from space does something odd. It absorbs and radiates such a “prodigious amount of heat that it cannot possibly be classified as lying within the habitable zone”. When observed from afar, the temperature of the Earth is hotter than that of Venus, despite being 30 percent further away from our parent star. “To stay in thermal equilibrium with the Sun, the Earth must radiate more thermal energy, and it does so at the long wavelengths of infrared.” Life on earth has evolved to modify the planet’s habitability, and thus ensure its own continued survival through the chemically mediated absorption and dissipation of heat from the Sun. We are all of us dissipative systems; stars, planets, and organisms alike.
With that definition out of the way, let’s now ponder the existence of a familiar organism from the standpoint of thermodynamics; the carrot. Queen Anne’s Lace (or Daucus carota) is the ancestral form of the now orange rooted umbellifer we know and love in everything from hummus to minestrone soup — the domesticated, orange carrot, Daucus carota subsp. sativus. Archeologists posit that the carrot has been intentionally cultivated by humans since at least 2000–3000 BCE, being slowly and ceaselessly transformed over those millennia into the factory farmed grocery store staple we know today. But before we get to the environmental burden of a modern carrot farm, know that even when our ancestors were foraging for wild carrots centuries ago, there was an entropic cost extolled by nature, having grown those plants of her own accord, but also a cost attributable to our search and consumption of those plant roots as food, winding up, ultimately, in their expulsion. (Proving that for better or worse, just about everything in life goes to shit in the end.) Life cannot exist without being coupled to the creation of entropy, but the important point here, is that not all manners of entropy production are equal, and it’s sometimes prudent to keep track.
To tally the entropy of a wild carrot that has taken root in soils of temperate, partially shaded biotopes, one “simply” needs to do some back of the envelope accounting. First, we must calculate the total negative entropy wrought by the carrot’s propensity for sunbathing. The calculations for total entropy production start off in the hole, as a negative value, as the sunlight absorbed over the course of the plant’s life counts as “free” energy. From there, we can begin adding to the ledger. We must then account for the net production of the plant’s photosynthetic products over the course of its life. Such products, (photosynthates) are themselves negentropic chemical structures; stores of energy that require energy to be produced. Such products are primarily sugars like sucrose and fructose, which, if they aren’t immediately used in the construction of more complex polysaccharides like cellulose, wind up being transported from the plant’s lace like leaves to its root, where they’re converted into starch, a polysaccharide far more resistant to solubility — which sees the fleshy biomass of a carrot serving as backup battery built as insurance on its own survival. But no biological process is perfectly efficient. The photoelectric transformation of light energy into the chemical potential energy stored in the carbon bonds of sugars is far less than ideal. On paper, its theoretical maximum sits at 26% efficient, in reality over the course of a growing season, its actually closer to 1%. Energy, in the process, is wasted as heat — as entropy. And so even in the transformation of “free” sunlight into living matter, we begin to see cracks creep in. From there, we must consider all it takes to keep our wild carrot alive, beyond sunlight. The positive entropy created by photosynthesis also constitutes waste gasses, not just oxygen but ultimately carbon dioxide too. It is a common misconception that plants of all sorts simply breathe in carbon dioxide and expel oxygen. Plants do do those things via photosynthesis, but they don’t simply harness the light of the sun, water from the soil, and carbon from the air for our benefit. As autotrophs (organisms capable of manufacturing their own food) they must at some point consume the carbohydrate foods they produce via respiration, same as us. They burn (as in, literally combust) their sugary fuels in the anabolism of the proteins assembled, polymers stitched together, and complex organic molecules (like carotene) transported round their bodies in service of their own survival. When the inputs are tallied up against the wasted outputs and the products of that equation deduced, we find entropy’s numbers to always be positive. But positive entropy implies disorder in contradiction with the ordered body of the carrot itself.
Which begs further philosophical questions… What is the carrot “itself”? Where does the carrot begin? In the fusion reactions of hydrogen into helium in our host star 6 light minutes away? Or in the ground beneath our feet? Likewise, where does it end? At maturity, once it’s gone to seed? Or only after its been eaten and transformed into another living body? Regardless of those questions, over the course of a carrot’s life, the carrot does not only exist, it persists.
What is important in this dissection is an understanding of locality. In the localized reference frame of a carrot, entropy decreases by way of the visible order intrinsic to its shape and form, as the carrot builds itself into itself all the way down the organelles and proteins and organic molecules within its cells. But when considering the contextual scope of such localized systems, the quest towards a truer picture implores us to look beyond them. Order can only be created in the supposed violation of the second law if the system is said to not be closed, but open. The entropy of a closed system increases unabatedly towards a maximum, but an open system, one that has the capacity to funnel energy into itself and waste products out, can maintain its own order at the expense of the order in its surrounding environment; by way of the transfer of energy and matter from outside to inside and back out again, carrots cease to be idealized locally isolated systems.
Carrots, like all things in heaven and earth, are open to interaction. Whereas isolated systems tend toward equilibrium (maximizing internal disorganization), open systems tend to maximize external disorganization by creating pockets of self-organization adeptly structured for energy dissipation than any randomly arranged alternative. There is truly only one closed system to consider; that of the universe itself. Upon the examination of the many semi-permeable boundaries that populate our world, we find everywhere pockets of asymmetrical energy distributions that tap into the flexibility of the second law’s maxims by way of variable forms of mediation across membranes, skins, and selves. I hope you never look at carrot peels in the trash the same way ever again.
In considering the metaphorical wild carrot beyond its service as synecdoche, we invariably trace our way to the state of the food system at large. To tally the entropy of a wild carrot seems simple in comparison to what it would take to discern the boundaries of all of agriculture in the hopes of being able to identify and corral its superfluous entropy production.
The modern industrial agricultural system is responsible for some 10–12% of all anthropogenic greenhouse gas emissions, when measured from the cradle to the gate (the moment of the commencement of an agricultural process, to its readying for human consumption) but is much greater when that assessment stretches from the cradle to the grave, incorporating transportation, distribution, human consumption, and disposal. Ultimately, it makes sense that the fuel source at the base of the pyramid of human existence — food — should be so broad and wide. Agriculture defines the portion of the human endeavour concerned with the incessant production and consumption of low entropy, energy dense matter our species requires to subsist; carrots and cows alike. But for the majority of human history, that requirement was not wrought from any explicit cultural undertaking. It was tapped from the wild and living world of our immediate environs. Today, we extract from the ground the banked low entropy bodies of fossilized plants and alga to subsidize the immense effort of feeding humanity under the pretence of efficiency, when in reality, we’re pilfering from a bank account full of equally hard-earned credits that was opened hundreds of millions of years ago. When we burn hydrocarbons, the end products of those reactions, water vapour, carbon dioxide, methane and more, all count as small, easily disorganized, light molecules, far higher in entropy than the clunky, heavy chains of carbon and hydrogen we mined out of the earth. In most developed nations just 150 years ago, 50% of their total work force was involved in agricultural production. Today that number is just above 1%. Human blood, sweat, toil, and tears — all sources of human entropy — have long been replaced with mechanical, petrochemical, and industrial sources of entropy stripped from the earth, and leached into the atmosphere.
To name a thing helps us see it. To number it helps us hold it. Though the accurate quantification of entropy seems in practice, impossible, it has not stopped brave academics in the (literal) fields of applied agricultural studies from trying. Even at its most quantized, the rigorous study of fractionated portions of the food system gives us a holdfast by which to perceive the paradoxical beast that is simultaneously of our collective, yet no one’s creation. The methodology of a life cycle assessment (LCA) attempts to craft a means of accounting for the accumulated impacts of bringing most anything into existence under capitalist systems of extractive labour and production. It’s not just interesting, as in “nice to know”, it’s a way of pushing back on the invisible ledger of our collective socio-economically borne entropy production. Entropy has deep links to information theory; “doing” and “knowing” are based in the same laws. Knowing anything for certain requires work. Work levered against the eternal accumulation of uncertainty. Much in the same way physico-chemical work is levered against the eternal accumulation of disorder. The disorder filled external environment of the wild carrot — the air around it, the soil adjacent — becomes something else entirely when you consider the roughly half a trillion farmed carrots grown every year (of our own accord). They become “externalities”. And externalities can be insidious.
Paul Ehrlich once said: “If communism failed because of its inability to accurately represent true market value, then it could be said that capitalism will fail for its inability to accurately represent true ecological value.” Those failures of ecological representation are ultimately what LCA’s try to correct. But they are nebulous, unruly, notoriously difficult assessments to undertake. Why? For the same reason that no single carrot can be considered an isolated system. Hyperobjects are what ecologist Timothy Morton dubs “objects so massively distributed in time and space as to transcend spatiotemporal specificity.” And hyperobjects on the scale of the agricultural sector are constituted by systems within systems within systems. Compounding complexity all the way down. The beauty of the porous boundary, the skin of the carrot, becomes a pandora’s box when viewing an industrial carrot farm as the sum total of inputs into, and entropic outputs out from, a determinate boundary for the associated energy expenditures to sit within.
LCA’s must ask questions that don’t always have definite answers. What? How much? For how long? How many times? Where? How well? Compared to what? Question that can sometimes be precisely known, sometimes not. But the most crucial questions relevant to the success of these assessments hinge on clearly defined boundaries. At times, where the lines we choose to draw in the sand fall can feel suspiciously congruent to the lengths along the beach we’re willing to walk. For a carrot, the star responsible for firing its photosynthetic pathways sits firmly “over there” 150 million km away. We can safely discount the sun’s inclusion within the boundaries of such assessments — it is not a proximate factor we have any capacity to affect. But within the set of proximate factors we could have sway over, there are infinite issues of delimitation. The more questions you ask, the more you pull at the threads in question, the more you realize those threads are actually a web that wraps itself around the entire world several times over. Agriculture is not an isolated portion of the human endeavour; it is perhaps the best port of entry into the totality of it.
In LCA’s pertaining to carrots, one must be aware of all manners of entropy production, even if the buck stops before any given impact is included in the results. For example, in the organic farming of carrots, cover crops like clover or vetch, which are grown in alternating 5-year rotations, must have their own environmental impacts assessed, in consideration that their own lifecycles factor into the life of a harvest yet to come by providing green manure for the land’s fertilization. Conversely, for conventionally grown carrots, the industrial Haber-Bosch process requires an enormous amount of energy inputs to achieve the catalytic temperatures and pressures in excess of 500°C required to fix atmospheric nitrogen within furnaces into a solid, soluble, and bioavailable form. The sequestration of carbon into the soil must also be taken into account, because when it’s not, it becomes tough to see any presumed benefits between locally grown organic produce, and conventionally farmed carrots shipped by refrigerated cargo ships and relays of 18 wheelers to get from plot to plate. Perspective shifts in the assessments of greenhouse gas equivalent emissions also change the results of such studies wildly, depending on whether you measure their impact on 10 year, 100 year, or 500 time horizons. Methane, for example, produced in quantity in the fermentation chambers of ruminants that may provide a conventional farm with manure — a potential final destination for surplus grass feedstocks grown during crop rotation on an organic farm — is 80 times more potent than CO2, but breaks down in the atmosphere after only 9 years. Deep considerations the asymmetrical nature of nature yields conclusions that are anything but “flat”, spatially, temporally, relationally, try as we might to smear them onto spreadsheets, the flattest things imaginable. The point is that there are uncountable ways to view any given agricultural system, to chop up its processes in an attempt to get a handle on it. Like the distance round the shoreline of Australia, the finer your measuring stick, the longer your result; at a fine enough level of detail, in the fractal dimension, the coast of the island becomes infinitely long. But common sense tells us we can walk around it (in 2018, the aptly named Terra Roam became the first woman to make the roughly 17,000 km trek). Likewise, researchers do yield useful results from LCAs.
In a 2015 study of this very topic, Finnish researcher K.C. Raghu conducted and compared LCA’s of imported conventional grown carrots against both domestically produced conventionally grown, and organically grown carrots. The study is thorough, and clearly states its delimitations and its faults where research cannot see beyond the thick brush of a globally structured forest of trade. It admits as much: “Ideally, an LCA should start as the natural system ends and technological system begins. However, in agriculture, integration of a biological system as a part of the phase of production makes it complicated to isolate the technological sphere.” But still he yields insightful results: the domestic, organically grown carrots, on a per kilo basis, produced 97% less greenhouse gas emissions than local conventionally farmed carrots, and 99% less emissions than imported ones. Likewise, the energy demand for all three farming methods were 1.3, 1.9 and 3.7 megajoules per kilo of carrots respectively. We should never presume to know the results before the empirical evidence rolls in, but here, we see science bolstered by folk wisdom yet again. It’s best to eat organic food; or as your grandparents called it, food.
There are margins of error to these figures, of course. And as we’ve stated, there’s a certain degree of art to the arbitrary. This is where entropy as information is perhaps most succinctly understood. It would require an infinite amount of work to know with perfect certainty just what it takes to grow a carrot. But the point of these imperfect numbers is that at the very least, they’re consistently imperfect. They allow us to draw a ground floor upon which to stand on, look around, and visualize the broad details of those systems that prove untenable in their externalities. We are stuck here on earth with our choices in these matters. We can push the fuzzy boundaries of these studies to the brink, but ultimately the only real boundaries we have to contend with are two fold: the spherical horizon of our planet, and the infinite one of our imagination.
