Nitrogen Agriculture

The world’s factories now produce 144m tonnes of reactive nitrogen annually, far outstripping all the microbes of the Earth’s soils.

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June 6, 2017 – Online MCAT CARS Practice

Question: What is your summary of the author’s main ideas. Post your own answer in the comments before reading those made by others.

The most important thing about Mark Sutton is his contribution to the world’s efforts to clean up nitro­gen pollution, but that is not the most striking thing about him. With the earnest air of an English schoolboy of yesteryear, an ability to get into great detail about his enthusiasms very quickly and, on occasion, socks with his sandals, he is, give or take a scar and a few decades, the spitting image of Harry Potter.

Young Potter’s saga is about facing up to consequences: his life is entirely shaped by the unfinished business of great struggles fought at and before the time of his birth. So is Sutton’s saga. A professor at the Centre for Ecology and Hydrology just outside Edinburgh, he is devoting his career to reining in the adverse effects of one of the most profound transformations of the 20th century.

In the late 1800s leading chemists such as William Crookes, Henry-Louis le Châtelier, Wilhelm Ostwald and Fritz Haber realised that if Europeans were to continue to enjoy the benefits of higher output of both wheat and ammunition (the manufacture of which needs reactive nitrogen), new sources of nitrogen would have to be found. Nitrogen is not exactly hard to come by — it makes up 80% of the atmosphere — but that atmospheric form of the element is inert and living things can use it only when it is in reactive form. Lightning can make the necessary changes; but before humans took a hand in it the hard graft of providing nitrogen in a form that could be used to make vital protein and DNA was mostly undertaken by microbes.

But the needs of a growing technological civilisation outstripped what the bacteria could offer; it was time, as Crookes put it, for “men of science” to take a hand; if they did not the world faced “a catastrophe little short of starvation…and even the extinction of gun powder!” The problem of making reactive nitrogen from the air was solved a decade later by Fritz Haber, and both munitions and agriculture were changed for ever. After the second world war nitrogen fertilisers were fundamental to huge increases in rich-world farm productivity; at the core of the “green revolution”, they transformed agriculture in many poor countries. That a population twice as large as that of 1970 is now better fed with no more agricultural land used in the process is down to this great fertilisation.

The world’s factories now produce 144m tonnes of reactive nitrogen annually, far outstripping all the microbes of the Earth’s soils. This deliberate commandeering of the nitrogen cycle is arguably the most profound of the many impacts humanity has so far had on its home planet. To capture the ambition of the undertaking Sutton and his colleagues sometimes refer to it as a form of geoengineering – a deliberate technological intervention on the scale of the great cycles of nature. (It is an analogy I develop in my new book, “The Planet Remade”.)

The world-changing benefits of this geoengineering have come with enormous costs. In the wrong places – which range from the inside of people’s lungs to the ozone layer, by way of dead zones in coastal seas, polluted drinking water and damaged soils – reac­tive nitrogen can do a great deal of harm. According to “The European Nitrogen Assessment”, a hefty tome Sutton and his colleagues produced four years ago, pollution by nitrogen-based compounds then cost the European Union between €70 billion and €320 billion a year; the whole world’s bill might handily top a trillion. Were it not for climate change, this would probably be the environmental problem the world discussed the most.

Clive Hamilton, an Australian philosopher, sometimes invokes the “sorcerer’s apprentice” sequence from Walt Disney’s “Fantasia” to illustrate the dangers of using geoengineering to avert climate change. Told to clean up his master’s chamber of secrets, Mickey enchants a mop and pair of pails. As they set to work the mouse nods off, only to be woken from a reverie of omnipotence by the Stakhanovite mop’s flooding of the workshop. Things are completely out of control when the magus returns, goes Charlton Heston on the waters, and disciplines his errant disciple. The lesson for geoengineering is that there are powers with which the Mickeys of the world should not meddle.

If you accept the nitrogen revolution as a form of geoengineering, though, this story gets stood on its head. It is the great magicians who cast the spell (Crookes’s rather fine beard and whiskers, along with his keen interest in spiritualism, would have made him at home in the Hogwarts staffroom), and the consequences of their magic are even greater than they intended. But these effects, though galling and costly, are not irreversible.

It is possible to clean things up – and this is what the sorcerers’ latterday apprentices are trying to do. Rather than dreaming on the job, they are taking a realistic look at the problem and putting together a grimoire of practical solutions. Instead of Fantasia’s thoughtless catastrophe, we see a mindful, incremental amelior­ation of unanticipated harm. Given that human sorcery is sure to change the planet further, and that no such intervention, any more than any other great magic, can be free of consequences, the example of diligence provided by apprentices like Sutton offers a modicum of comfort.

Adapted from 1843magazine.


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This was an article on Population Health.

Have a great day.
Jack Westin
MCAT CARS Instructor.
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  1. Nitrogen&geo-eingneer=problems irreversible=sutton=harry potter=fixing problem


  2. An anology of the manipulation of reactive nitrogen in geoengineering to magic. There are serious consequences to the problem and that even if you have the power to do so, you shouldn’t manipulate something that would bring consequence.


  3. – Sutton’s contribution
    – Sutton’s background
    – why Nitrogen fixation was needed
    – How Nitrogen changed the world
    -the current production of N
    – what are the costs
    – Comparison of Nitrogen production to Fantasia
    – costs, but not irreversible
    – what we need, authors final points


  4. Nitrogen and geo-engineering are problem but can be fixed


  5. MIP –> geoengineering = helped productivity, unintended consequences, Sutton = HP is helping to solve the problem of nitrogen pollution


  6. Although geoengineering of nitrogen has profoundly impacted humanity in a myriad of positive ways, it is impossible to ignore the deleterious consequences associated with the production of reactive nitrogen compounds.


  7. Nitrogen is an important source for agriculture and ammunition, and until the the late 1800s, scientists were able to create reactive nitrogen at a pace faster than microbes.
    The passage mentions the costs of creating reactive nitrogen, such as pollution and a large global bill.
    Ultimately, the author uses a philosopher to explain what its like if government does not regulate the creation of reactive nitrogen.


  8. Main idea is nitrogen pollution is an issue which can be solved. History of nitrogen agriculture is traced and current processes are referred to as geoengineering. Recurring analogy of magic (Harry Potter and Mickey Mouse) to emphasize people being in control of this phenomenon.


  9. reactive nitrogen dangerous + $, geoengineering = reversible


  10. Nitrogen reformation (GE)= costful to economy and environment. (7 paragraphs in)


  11. Industrial rather than biological nitrogen fixation has dramatically changed the face of agriculture, but it is not without costs to human and ecosystem health. Author seems hopeful though that others, brilliant as those able to fix nitrogen, will be able to reverse the changes made by reactive nitrogen and counter the problems it causes.


  12. The scientists behind the process of geoengineering are likened to novice discoveries (Fantasia) of scientists from previous decades. While The article lauds the benefits of geoengineering and its “magical” benefits provided to mankind, it concludes that the impacts of this process must be reigned in by more cognizant scientists (Harry Potter) who advocate for the cleanup of nitrogen pollution.


  13. Nitrogen pollution caused mainly by geoengineering; geoengineering makes lots of nitrogen but has drawbacks; negative effects can be reversed; ongoing efforts to resolve issue


  14. Theme: Sutton has committed his energy and career to reversing the adverse effects of geoengineering (nitrogen pollution). He is used as a contrast to the earlier chemists who started the nitrogen revolution as they found ways to harness nitrogen from nature and convert it to the reactive form (men of science, Fritz Haber). These people have inadvertently and unwittingly created problems for our environment. (central)

    While nitrogen fertilizers were ironically used to increase farm productivity in the so called ‘green revolution’ and transformed the agriculture of poor countries, it has led to negative impacts on the environment (most profound of the many impacts humanity has so far)

    Deliberate technological intervention of nature has cost us lung cancer, ozone layer depletion, destruction of coastal life and habitats, pollution of safe drinking water and damage to your soil.
    Testable: Geoengineering is only second to climate change (Were it not for climate change)

    Testable: Sutton is to Potter as Haber and his compatriots were akin to the Hogwarts professors. Understand that author is describing Sutton as an altruistic sorcerer who is trying his best to correct the mistakes made by his predecessors (his life is entirely shaped by the unfinished business….before the time of his birth. So is Sutton’s saga; Crookes’s rather fine beard and whiskers….made him at home in the Hogwarts staff room….consequences of their magic are even greater….are not irreversible)

    Sutton is like Mickey in Disney’s adaptation of the sorcerer’s apprentice in Fantasia except that he is not going to nod off like Mickey and get enchanted mops to help him clear the mess (rather than dreaming on the job…..realistic look at the problem…instead of Fantasia’s thoughtless catastrophe…..mindful incremental amelioration of unanticipated harm). Sutton is going to be the conscientious do-gooder (putting together a grimoire of practical solutions….diligence provided by apprentices like Sutton).

    Also know that the author acknowledges that due to the enormity of the problems caused by geoengineering, there is little Sutton can do but it is still a form of respite (offers a modicum of comfort).

    Tone: imageries of magic conjured in this article, whimsical and playful (lessens the brevity of the content/ message author wishes to convey) to be used as a form of humor to balance the scale of destruction/pollution caused by geoengineering. Positive and optimistic (these effects, though galling and costly, are not irreversible….it is possible to clean things up)despite the consequences of our earlier folly. He feels that we have to be proactive and not let things be or worsen (lesson for geoengineering is that there are powers with which the Mickeys of the world should not meddle…..this story gets stood on its head).


  15. MIP: Sutton fights overproduced N (geoengineering); N pollution = reversible.


  16. MIP: new source of N2 (geoengineering) = expensive/harmful + can be reversed; tone = neutral


  17. author points out, ‘geoengineering’ of nitrogen by Haber is phenomenal. however, too much is anything is bad. now we are facing with problems with active nitrogen being too much abundant. it will not be easy but scientists like Clive is trying to reverse the problem.


  18. Geoengineering = harmful, the problem must be solve.


  19. Mark Sutton = geoengineer known for nitrogen; nitrogen = transformation of agriculture + costly + dangerous; consequences can be reversed + solutions for clean up; author = positive


  20. MP: finding ways to get usable N may be good, but perhaps its not best to meddle


  21. MIP
    (1) Geo-engineering = increase reactive nitrogen = impact world
    (2) Reactive nitrogen/ geo-eng. = harmful, costly, and irreversible

    Positive towards Sutton (who is trying to solve problem). Negative towards geo-eng and reactive nitrogen.


  22. Ignore previous!

    (1) Geo-engineering = increase reactive nitrogen = impact world
    (2) Reactive nitrogen/ geo-eng. = harmful, costly, and irreversible



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