by Michael Haag
To put it simply, both population and food production have expanded at similar rates, and the rate of increase in the food supply has actually been faster than that for population. In eighteenth-century England, for example, a farmer could expect to grow around a tonne of cereal per cultivated hectare; these days, Chinese rice farmers and US maize farmers alike reckon on yields of ten tonnes per hectare.
Insofar as Malthus can be said to have made any concrete predictions, therefore, he got them wrong.
That’s a very different issue, however, from saying that the human population can carry on rising indefinitely, without the planet ever reaching maximum capacity. The figure that’s cited by the Shade in chapter 22 of Inferno, that the global population is expected to exceed nine billion by 2050, is indeed the current estimate from the UN (not the WHO, to whom it’s attributed in the novel). That prediction includes a worst-case scenario in which the actual total reaches 10.6 billion.
As is argued in Chapter Eight of this book, the Earth will be able to feed nine billion or more within the next half-century. Our resources, and capacity for growth, are not infinite, however, and the population will indeed have to stabilise at some point. What the Shade fails to mention is that the UN report says that that will occur in 2075, when the population will peak at 9.22 billion, and that the numbers will decline thereafter. Exponential growth has in fact already all but ceased in the more prosperous countries of the world, and similar deceleration is confidently expected to occur in developing countries as the economic incentives to have large families diminishes.
Focusing exclusively on Malthus’s mathematics in any case serves to obscure the fact that the primary purpose of the Essay was ideological. Everything Malthus wrote was coloured by his moral beliefs, and his equations were designed to illustrate his views about equality. Such views continue to be widely held today, and to underpin attitudes and approaches to population issues that can appropriately be called ‘Malthusian’ or ‘neo-Malthusian’.
CHAPTER EIGHT
Apocalypse Now?
For two hundred years, Malthusian fears have receded and resurfaced according to the preoccupations of the time. The last upsurge came in the late 1960s and early 1970s, when world population was growing at its fastest. In their 1967 book Famine 1975!, William and Paul Paddock predicted massive food shortages in India within a decade, and advised the USA against giving more food aid because that would only allow more children to be born into starvation.
A year later, in The Population Bomb, the American biologist Paul R Ehrlich announced: ‘The battle to feed all of humanity is over. In the 1970s hundreds of millions of people will starve to death.’ Extreme Malthusians predicted a ‘Great Die-Off’, in which four billion people would perish by the end of the century, while the Club of Rome think tank, in its best-selling 1972 report Limits to Growth, used an early form of computer modelling to show that a rapidly growing population was about to run into the brick wall of finite natural resources.
This chapter is an adapted version of Paul McMahon’s discussion of the prospects for global food production, in his 2013 book, Feeding Frenzy: The New Politics of Food.
However, Malthusian warnings have always been countered by equally strong ripostes from scientists and economists who have more faith in the human capacity for technological progress and social organisation.
The problem for the Malthusians is that as time passed, their apocalyptic predictions have repeatedly been proved wrong. Thus India in 1975, far from experiencing famine, was despite its rising population self-sufficient in food. Similarly, the new millennium arrived without an ecosystem collapse. The world’s population is now seven times greater than when Malthus wrote his treatise. People live longer and are better fed than before.
Nonetheless, we are living through another revival of Malthusian fears. A stream of doom-laden titles have rolled off the presses: Dan Brown’s fictional Inferno can be added to a list that includes The End of Food, Famine in the West, and Climate Change Peril. Some of the earlier prophets of disaster insist their predictions are finally coming true. Paul R Ehrlich, now professor of population studies at Stanford, is more pessimistic than ever, telling the Guardian there’s only one chance in ten of avoiding a collapse of global civilisation. Lester Brown, a champion of population control in the 1970s, writes in World on the Edge (2011) that ‘if we continue with business as usual, civilisational collapse is no longer a matter of whether but when’. After being almost taboo for two decades, population control is re-emerging as a valid subject for debate.
Rice being grown on terraced hillsides in Vietnam. Can we feed a world population that is predicted to exceed nine billion in 2050?
Neo-Malthusian arguments centre on the idea that we are using up finite resources. Figures are thrown around about how we are running out of land, water, biodiversity, fertiliser or fossil fuel. Climate change is cited as the great new threat, multiplying all the others.
How seriously should we take these warnings? First, we need to assess the biophysical potential for food production. If the laws of biology and physics simply prevent us from growing enough food to satisfy everyone’s needs, we have an insuperable problem. For the moment, therefore, let’s put economic and political considerations to one side, and pretend the planet is a single system that can be optimally managed to deliver food and other services for humanity. In this fantasy world, how much food can be sustainably produced?
A DOMESDAY BOOK FOR THE TWENTY-FIRST CENTURY
The notion of our planet as being ‘crowded’ implies that all the good land is already being used. People imagine that not only must any spare land that exists be under forest, but that we are losing precious farmland to urbanisation, industrialisation and environmental degradation.
The organisation best placed to know whether that’s true, Dan Brown would surely be delighted to discover, can be found in an eighteenth-century palace outside Vienna. The International Institute for Applied Systems Analysis (IIASA) devotes itself to tackling issues like energy and climate change, food and water, poverty and equality. Inside its Habsburg-built headquarters, grand staircases lit by crystal chandeliers lead to rooms with stuccoed ceilings, while outside a former royal deerpark offers a soothing backdrop. However, the mathematicians, scientists, economists and engineers within are more interested in the results coming out of their computers.
Over the past fifteen years, a team led by German mathematician Günther Fischer has pulled together data on soils, terrain and climate – the three factors that determine the suitability of a piece of land for agriculture – to create a map of Global Agro-Ecological Zones. For each of its 2.2 million grid-cells, they have calculated which crops can be grown, and what yields expected, predicting how much food can be produced under different farming systems. It’s a twenty-first-century version of the Domesday Book, the survey of England commissioned by William the Conqueror in 1086.
The former Habsburg palace that houses the headquarters of the IIASA.
The IIASA model shows that about a quarter of the world’s land mass (excluding Antarctica) is not productive: 22 per cent is occupied by desert, mountain, inland lakes or rivers, while 3 per cent is used for human settlement. A further 28 per cent is under forest, and 35 per cent covered by grassland or open woodland. Most of our food comes, therefore, from the remaining 11 per cent.
Fischer and his team conclude that 3.1 billion hectares of additional, uncultivated land is agro-ecologically suitable for rainfed crop production. That is, if properly cleared and prepared, this land has the right climate, soils and terrain to deliver acceptable yields, without having to rely on irrigation. If we exclude forest, and protected areas like national parks, the figure drops to 1.3 billion hectares of grassland and open woodland suitable for agricultural expansion – equal to 80 per cent of all the crop fields today.
These figures disguise big disparities. Populous regions like southern Asia, the Middle East and western Europe are already maxed out. Nort
h America, by contrast, could expand its cultivated area by more than half, and so too could the Russian Federation and eastern Europe. But the two regions with by far the biggest potential are South America and Africa. Home to almost 60 per cent of the suitable land, they could triple the amount of land under crops.
While IIASA’s modern-day Domesday Book does not support a doomsday conclusion, it only tells us what is biophysically possible. In the real world, actually bringing this land into production would pose enormous social, economic and environmental challenges. And there would be trade-offs. The clearing of grasslands and open woodlands would affect the carbon balance, destroy biodiversity and deprive pastoralists of the grazing lands on which they depend.
For that reason, it would be preferable to get more food out of existing farmland. There’s a huge difference in productivity between the world’s most and least developed farming systems. An Iowa corn farmer, or a Vietnamese rice grower, can produce ten times more grain per hectare than a poor farmer in East Africa. Bringing the least productive farmers up to even half the level of the most could double or triple the total amount of food – and help tackle rural poverty in the world’s poorest regions.
Can the so-called ‘yield gap’ be closed? If nature has dealt certain countries a losing hand in terms of soil, terrain and climate, there may be only so much we can do. Thus while northwest Europe is blessed with fertile, humus-rich soils, long periods of summer daylight and the warming influence of the Gulf Stream, parts of Africa are cursed with nutrient-poor soils, variable rainfall, periodic heatwaves and virulent pests and diseases. It’s important not to overplay such differences, however. Most populated regions lie between these extremes, and many of those with low-yielding agriculture possess adequate soils and a good climate.
Comparing actual food production with biophysical potential has allowed Fischer’s team to demonstrate that no country achieves the maximum attainable yields. Western Europe and eastern Asia get close to 90 per cent; North America only attains 70 per cent; and South America, eastern Europe and Russia produce just under half. But the region that stands out is sub-Saharan Africa, where yields are less than a quarter of what’s possible. Large areas of Africa contain fertile soils, abundant rainfall and terrain suitable for agriculture, with maximum attainable yields just as high as in North America or Europe. In theory, African farmers could triple their output without putting any new land under the plough.
The yield gap has more to do with the human environment – poor infrastructure, lack of skills, limited access to finance and technology, unclear land rights, unbalanced trade arrangements and so on – than the natural environment. To quote Akin Adesina of the Alliance for a Green Revolution in Africa, the problems facing African farmers today are ‘a result of missed opportunities and decisions made by governments and international institutions rather than a result of stubborn facts’.
So far, we have considered the planet’s potential for food production under current conditions. What if the climate changes? Supercomputers the world over are struggling to estimate the potential impact of climate change on agriculture. No one knows what quantity of greenhouse gases will be in the atmosphere; how this will in turn affect surface temperatures, precipitation and plant performance; and the effects of droughts and floods. However, the broad conclusions for the next forty or so years are not as bleak as might be expected. Yes, agricultural production in the mid-latitudes and tropics is likely to be negatively affected, but the high latitudes – places like northern Europe, Canada and parts of Russia – will experience increased productivity. The 2007 assessment of the Intergovernmental Panel on Climate Change actually concluded that global productivity would slightly increase.
That said, the planet is only expected to warm by about one degree before 2050. Things will really heat up after that, which will cause a lot more problems for agriculture. Indeed, the latest research indicates the world is warming more quickly than expected. Thus, while climate change should not prevent us from producing enough food between now and 2050, it’s definitely something to be worried about. Feeding a world of nine billion in 2100 might be a much more difficult matter, if we continue on our current path.
TO FINITY AND BEYOND
While ‘modern’ agricultural methods can improve the potential of soils, terrain and climate, there are question marks over their sustainability. The two principal charges levelled against agriculture are that it uses non-renewable resources such as oil, natural gas, and water, and that it destroys our environment by polluting water, shrinking biodiversity, clearing forests and pumping out greenhouse gases.
Concerns about fossil fuels usually run along these lines: in industrialised nations it takes the equivalent of seven calories of energy to deliver one calorie of food; most of this energy is derived from fossil fuels, which will eventually run out; therefore, our current food systems are in danger of collapse. Thus Dale Allen Pfeiffer, in Eating Fossil Fuels, argues that in order to return to relying solely on the energy provided by the sun, the world’s population will have to fall to a sustainable capacity of about two billion. In ultra-Malthusian fashion, Pfeiffer predicts a great human ‘die-off’.
No one expects crude oil to run out within the next fifty years, but it is indeed likely to become scarcer and more expensive. Four-fifths of the energy consumed in food systems in North America or Europe is used to transport, store, process, retail and cook food. There’s enormous scope for energy efficiency all along this chain. While diets in wealthy countries might have to become less resplendent, more local, people wouldn’t starve; indeed, they would probably be healthier.
The single greatest energy input in modern farming is nitrogen fertiliser; almost half the people on Earth are fed thanks to manufactured nitrogen fertiliser. While there’s no shortage of nitrogen in the air, it needs to be ‘fixed’ via the Haber-Bosch process, which mostly uses natural gas. Many ‘doomsters’ see this as the weak link in the global food system. That view was particularly prevalent in the US in the early 2000s, when experts predicted that domestic gas reserves would be gone within decades. Since then, however, the widespread use of hydraulic fracturing (or ‘fracking’) has turned scarcity to abundance. Although environmental concerns remain about this technology, US natural gas production is up fourteen-fold since 2000. What’s more, even if natural gas reserves were to be exhausted, the Haber-Bosch process is not the only way to produce nitrogen fertiliser, just the cheapest. We could turn to other technologies, and power them with renewable energy.
The other critical fertiliser, phosphate, is derived from mining, and thus a more finite resource. Estimates of remaining reserves depend on balancing the cost of extraction against the market price, and vary from the US Geological Survey figure of one hundred years’ worth, to a more recent study that suggests more like four hundred years. In addition, most phosphate is eventually flushed into the sea, and there may be opportunities to increase its capture and recycling.
The most important ‘input’ for agriculture, however, is water. Over the past decade, the notion of ‘Peak Water’ has become a popular apocalyptic theme. Water is depicted as another finite resource through which we are remorselessly working our way, with agriculture, because it accounts for more than two-thirds of freshwater use, seen as the chief culprit. The same statistics appear again and again: that it takes 1,300 litres to make a loaf of bread; 3,400 litres to grow a kilo of rice; 3,900 litres to rear a kilo of chicken; and anywhere between 15,000 and 100,000 litres to produce a kilo of beef.
But this is a simplification. Most of the water ‘used’ in agriculture is taken up by the roots of plants, transpired via their leaves as water vapour, and falls somewhere else as rain. The same goes for animals grazing on pastures; most of the water in the grass they eat returns in the form of urine and dung.
Although regions such as northern China, India’s Indo-Gangetic plain, and much of the western US are in water deficit, there’s no global scarcity of freshwater. Europe only withd
raws six per cent of its renewable resources, and Asia only twenty per cent. The problem is not a lack of water, but that water is inaccessible because the right infrastructure is not in place. What’s more, farmers use water inefficiently. Almost nine-tenths goes on flood irrigation, which maximises the losses; eleven per cent goes through sprinklers; and only one per cent through drip irrigation, the most efficient by far.
Agriculture is also a major cause of climate change. Farming activities are responsible for around thirteen per cent of greenhouse gas emissions. The production and application of nitrogen fertilisers can lead to the release of nitrous oxide, a greenhouse gas three hundred times more potent than carbon dioxide, while livestock production can produce large amounts of methane. Indirectly, agriculture can also be blamed for a large proportion of deforestation. Altogether the production of food could account for close to one-third of man-made annual emissions, more than all the world’s factories, cars and planes. To limit global warming, we will have to reduce these emissions.
Legitimate questions surround the sustainability of modern agriculture. We need to find food systems that damage the environment less, while using non-renewable resources more efficiently. The good news is that alternatives exist. Many agricultural systems produce fewer greenhouse gases, or even act as carbon sinks, build soil fertility and preserve watersheds. They also tend to consume less energy. At the same time, they produce large amounts of food at an affordable price and deliver good profits to the farmer. These systems do not require new technology or major scientific breakthroughs, and are being successfully implemented all around the world right now. The challenge will be to scale them up.
FUNGIBLE DEMAND