Australasian Science: Australia's authority on science since 1938

Beating the Global Food Crisis

By Julian Cribb

In the first of a two-part series Julian Cribb looks at what is driving global food insecurity – and how we can overcome it.

Since 2008 there have been three world food crises, with a fourth possible in 2013 according to the United Nations.

Last night 216,000 more people sat down to dinner than dined the day before. While its growth rate is slowing, the human population continues to expand. On present trends it could reach 10, and possibly 11, billion people by the 2060s.1 At the same time, the demand for protein of nations like China, India and Brazil is soaring. Within half a century these factors will double global food demand.

By the 2060s we will require around 600 quadrillion calories every single day to feed everyone. And we will have to keep on producing them for more than half a century – until the women of the world can safely bring the population down to a more sustainable figure: perhaps 4–5 billion. The central issue in the 21st century will be whether or not we can achieve and sustain such a mighty harvest.

Many people see this as a simple problem: just apply more technology, as we did in the Green Revolution, to redouble agricultural production. However, food systems worldwide now face critical limitations. There are time bombs ticking in each of the major resources needed to secure our food supply – in water, land, nutrients, energy, technology, skills, fish, finance and stable climates.

Too long ignored is the dangerous synergy between these critical scarcities. Each compounds the others, raising the risks of unexpected tipping points – and unheralded food crises.

Like the Indian fable of the blind men feeling the elephant, we seem unable to grasp the whole beast – or the shadow it casts upon our future.

For example, high-yielding supercrops are no solution if there is not enough oil, soil, water or fertiliser to grow them. Alone, they do not solve the issues of food security or of hunger.

Food is now a wicked problem, requiring complex solution at the global level and by the whole human species.


Today the average person uses 1240 tonnes of water per year. In a lifetime each of us will use enough fresh water to float the world’s largest aircraft carrier – more than 100 kt.

Worldwide, groundwater extraction is presently 4000 km3/year. So massive is the mining of water it actually contributes 13% to sea level rise!

The most dangerous ticking time bombs for water are in northern China (which feeds 400 million), the northern Indo-Gangetic region (which feeds 1.3 billion) and the midwestern United States, all of which are forecast to exhaust key groundwater resources in 15–20 years.2 At the same time major food-producing regions such as North Africa, the Middle East, sub-Saharan Africa and Central Asia face critical water scarcity.

Less predictably but more seriously for food security, climate change appears to be affecting the reliability of rainfall over the world’s great grain bowls. On top of this there have been destructive floods in Pakistan, China, Australia, the US, Thailand and parts of Europe.

There have been notable declines in snowpack on high mountain ranges, and in inflows to lakes, rivers and aquifers in dry lands.3 Vast water bodies like Lake Chad, which feeds 40 million, have all but vanished in the past 25 years.

The International Water Management Institute has warned that world food production faces critical water scarcity as early as the 2030s.4 This is especially the case in Asia, where seven countries are presently withdrawing water at unsustainable rates,5 and water scarcity is emerging as a major threat to economic growth.

Water is one of the largest food time bombs – and is primed to explode within one or two decades. A sign of this are the rising tensions worldwide between farmers and other users, notably the gas, oil and minerals sectors6 that are mining groundwater that may be needed for future food and drinking uses.7

By the 2050s the cities will be home to 7–8 billion, and their voracious demand for water will double to around 2400 km3/year.8 To feed this demand, unless they desalinate or recycle, cities could steal up to half the world’s supply of farm water. This will make the task for irrigation farmers of doubling food production almost impossible.


Land loss and soil degradation are a major physical threat to our future. It is estimated that human activity causes the loss of 75–100 billion tonnes of topsoil per year.9 An FAO satellite study found we have been losing <1% of our farm land every year since 1990.10 Put bluntly, each meal you eat costs the Earth 10 kg of topsoil.

Despite appearing plentiful, soil is finite. Its formation takes thousands, even millions of years. Authoritative commentators say that if present rates of loss continue, the world could largely exhaust its arable topsoils within 50–70 years.11

At the same time we may already have passed peak farm land. FAO statistics indicate the global farmed area has contracted in 8 of the past 10 years,12 possibly due to urban expansion. The FAO’s latest State of Land and Water report indicates that around half the Earth’s land area is badly degraded or useless, while only 10% is thought to be improving.13

It is difficult to predict when the soils time bomb will explode – in regions such as the Middle East and Central Asia it is close to detonation. In Asia it will become critical within two to three decades. Europe, North and South America and Russia represent reservoirs of good soil, but are still losing it at unsustainable rates.

Most places are likely to experience the impact as a decline in crop and pasture yields, in spite of technological advances. Eventually tipping points will be reached in the form of regional famines. The “global land grab” by Arab states, the US and China among others is an indicator of coming land scarcity. A new book, The Global Farms Race: Land Grabs, Agricultural Investment, and the Scramble for Food Security (Woodrow Wilson Centre) estimates that an area the size of Western Europe has been “grabbed” by wealthy powers since 2001.14

We now need to face a second inconvenient truth – that every extra tonne of food we produce raises the risk of what the FAO described as a “progressive breakdown in productive capacity”. The system we have used for growing food agriculturally for the past 5000 years may not, in fact, be the main system whereby humanity feeds itself in future: this is a thought we now need to consider.

By 2050 gigantic conurbations like Guangzhou-Shenzen-Hong Kong, may have as many as 120 million inhabitants.15 Cities like Manila and Jakarta will have populations of 40–50 million.The world’s cities will together occupy an area of good soil the size of China. They will consume one-third of the world’s water and 80% of its nutrients.

Yet the modern city produces next to none of its own food. It is fed by a river of trucks that flows every night to restock the shops and supermarkets. To feed a city of 20 million requires the physical delivery of more than 6000 tonnes of food every day.16 To deliver Australia’s food requires about 80,000 truck movements per week. What happens if – due to an oil crisis, a war or natural disaster – that transport river fails?

The answer is supplied by Australia’s Sunshine Coast: during the 2011 floods, supermarkets were stripped bare in less than 48 hours. The modern city and society cannot survive more than a day or two without oil and without food so each of the world’s mega­cities represents, in its own way, a ticking time bomb.


Agriculture and food production use about 30% of the world’s energy. Each day the average consumer “eats” 4.1 litres of diesel fuel embodied in their food (along with about 29 kg of soil and 2.2 tonnes of water).

Global peak oil was in 2006, according to the International Energy Agency17 – but the peak is less important that when the scarcities and high prices begin. Critical to this are the 61 million new cars that will hit the world’s roads this year.18 The global vehicle fleet is currently forecast to grow from 750 million today to around 1.2 billion by the 2020s – 8% per year.

Global oil production, however, has grown by only about 0.7% per year since 2000.19 Growth in world car production now exceeds growth in world oil production by an order of magnitude, increasing the likelihood that an oil-driven tipping point will impact global food security.


Ours is the first generation in the whole of human history to waste one-third of our food.The average affluent family throws an entire shopping trolley’s worth of food in the garbage every month.20

Much of the world’s food security depends on a supply of cheap fertilisers. Yet phosphorus, potash and natural gas (used to make nitrogen fertilisers) are all finite and will become scarce and costly by mid-century.21 Phosphorus is currently expected to peak somewhere between 2035 and 2060 – but of far greater concern is that 85% of the world’s high-grade supply is controlled by a single country, Morocco.22 World supplies of potash are dominated by two countries – Canada and Russia.

As there are no substitutes for these nutrients in agriculture, the risk of a major tipping point is at least as high as an oil shock. While it is not easy to predict the timing of the explosions of nutrient time bombs, they will take the form of very steep price rises and reduced availability of fertilisers, making them unaffordable to most farmers in both the developing and developed world – with catastrophic impact on yields and on food supplies.

A separate dimension is the rapid depletion in soil micro­nutrients, meaning that today’s foods are less healthy and nutritious than they were a century ago.23 This is linked to a rising global incidence in heart disease, cancers, premature deaths and soaring health care costs.


By 2060 world demand for animal protein is forecast to reach 570 million tonnes.24 That includes an extra 100 million tonnes of fish – which will not come from the oceans because the wild catch peaked in 2004.25 So, another ticking time bomb is the need to produce around 5 billion tonnes of feed to raise all these animals, poultry and fish on farms.

To do this with grain alone we would need to discover three more North Americas to grow enough grain. We must also factor in an increasingly unreliable climate and uncontrolled land degradation. So, whatever these future livestock eat – it won’t be grain as it will be too expensive and reserved mainly for human food.


One of the reasons for the recent global food crises is that governments, aid donors and scientific institutions have cut back funds for agricultural and food research over several decades. This partly explains why growth in crop yields is not keeping pace with growth in food demand.

Today, the world invests about $50 billion per year in food and farming research.26 That’s roughly what we were investing when there were only 3.5 billion people on Earth.

Today the world also spends $1600 billion per year on new weapons.27 So we spend 30 times more on better ways to kill one another than we do on better ways to feed one another.

The starvation of the world’s food science research effort is a ticking time bomb of a different sort. Since it takes decades for new technologies to be adopted by farmers worldwide, the shockwaves can extend a generation or more beyond the original decision to cut R&D.

Climate Change

The Holocene climate in which agriculture was born is changing – probably forever. As the UN World Climate Conference, the World Bank and PriceWaterhouseCoopers have all warned, 2°C of global warming is now unavoidable and 4–5°C is likely.28 The largest droughts, floods and storms of recent years are now strongly linked to man-made climate change.29

Beyond 2°C, on an increasingly violent planet, grain production is especially is at risk.30 And with 4°C the World Bank says there is “a significant risk of high-temperature thresholds being crossed that could substantially undermine food security globally”.31

Current scientific estimates suggest that each degree of global warming could cost us about 10% of world food output.32 This makes current official predictions about the size of the world’s food security target perilously unrealistic. Instead of doubling, we could well end up halving the global food supply.

The Challenge

I have reviewed eight of the ten major ticking time bombs in the global food security outlook. Summed up, the challenge they present is to double global food production with half the present fresh water, much less land, no fossil fuels (eventually), scarce and costly fertilisers, less technology, inadequate research investment and growing climate instability.

This challenge appears daunting yet it also harbours magnificent opportunity, especially for countries such as Australia with the skills to respond sufficiently and in time.

This is the challenge of our age.


  1. Current UN forecasts are for 9.2bn by 2050. Each of the last five 1-billion increments in human population has taken an average of 13 years. The UN assumes the next two will take 40 years. Also, they do not appear to allow for increased life expectancy. As population is also heavily influenced by poverty levels, assumptions about economic growth in poor countries are relevant, as are rates of urbanisation of rural people and education of women.
  2. Groundwater and Global Change, UNESCO 2012
  3. Climate Science 2009–2010: Major New Discoveries. A Strong, K Levin and D Tirpak, International Resources Institute, December 2011.
  4. Out of Water, C Chartres and S Varma, FT Press 2011
  5. Resource Efficiency: Economics and Outlook for Asia and the Pacific, UNEP 2011
  6. Demand for Energy Tests Water Supply and Economic Stability in China and the U.S., K Schneider, Circle of Blue, June 2011
  7. also
  8. Projection based on current urban demand of 1.4 cu kms (IWMI)
  9. Human Health, the Nutritional Quality of Harvested Food and Sustainable Farming Systems, JB Marler & JR Wallin, 2006, also The Global Food Crisis, B Sundquist, 2008
  10. Bai ZG, Dent DL, Olsson L and Schaepman ME 2008. Global assessment of land degradation and improvement 1: identification by remote sensing. Report 2008/01, FAO/ISRIC –
  11. Marler& Wallin and Sundquist B, op cit.
  12. Data from FAOSTAT, 2012
  13. FAO State of Land and Water report, Rome, Dec 2011
  14. See Kugelman M et al. The Global Farms Race: Land Grabs, Agricultural Investment, and the Scramble for Food Security, Woodrow Wilson Centre, 2012. Also Deiniger K et al., Rising Global Interest in Farmland. World Bank, 2011
  16. Urban Agriculture: a response to crisis. A Drescher. RUAF 2005.
  17. Birol F., International Energy Agency (IEA) in interview with ABC:
  18. International Organisation of Motor Vehicle Manufacturers (OICA).
  19. USEAI 2012
  20. Gustavsson J, et al., Global Food Losses and Food Waste, FAO, Rome 2011
  21. The story of phosphorus: Global food security and food for thought, D. Cordell, J Drangert, S White, Global Environmental Change, May 2009.
  22. Grantham J.
  23. Op cit. Marler & Wallin, 2006
  24. FAO High Level Export Forum, How to feed the World: Investment, Rome, October 2009.
  25. Merino, G., et al., Can marine fisheries and aquaculture meet fish demand from a growing human population in a changing climate? Global Environ. Change (2012), doi:10.1016/j.gloenvcha.2012.03.003
    Also State of the World Fisheries and Aquaculture (SOFIA) 2010 (FAO 2011).
  26. J. Alston, J.M.Beddow, P. Pardey, “Mendel versus Malthus: research, productivity and food prices in the long run,” University of Minnesota, 2009.
  27. Perlo-Freeman S., et al. Military Expenditure, Stockholm International Peace Research Institute (SIPRI) Yearbook, 2011
  28. and
  29. World Bank, November 2012, op cit, p18.
  30. Climate change already hurting agriculture. S Reardon. Science, 5 May 2011
  31. Turn down the heat: why a 4 degree world must be avoided. World Bank, November 2012.
  32. Warming World: impacts by degree. US National Research Council, 2011.

Julian Cribb is a science writer and author of The Coming Famine (UCP 2010). In the next issue of Australasian Science he will outline solutions to the challenge of feeding 10 billion people. This article is based on a paper presented to the Australian Academy of Science’s 2nd Earth System Outlook Conference.