Hard to swallow but food security threat is very real
It's intrinsically scary: 7 billion people, growing to 9 billion. Can we feed them all? Already, obviously, we don't. But climate change could make global food insecurity much, much worse
Paddy Manning | Sydney Morning Herald | December 3, 2011
This week, coinciding with the opening of the United Nations' climate talks in Durban, we've seen Oxfam warn that extreme weather threatens food security - from the drought in the Horn of Africa to heatwaves in Russia destroying crops, to heavy monsoonal rains pushing up rice prices in south-east Asia.
On Monday, the UN's Food and Agriculture Organisation (FAO) warned that widespread degradation and deepening scarcity of land and water resources have placed many important food production systems at risk. No region is immune.
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So what? Callously, we have grown somewhat used to watching poor people starve overseas. If the world goes to hell in a handbasket, Australia likes to think it will always be able to feed itself.
Probably, we can. Huge land mass. Tiny population. We're protected (we hope). We are a big food exporter. We feed 60 million people, including ourselves, and this month the packaging billionaire Anthony Pratt called for Australia to quadruple its food production.
Yet we are also the driest inhabited continent and, as Ross Garnaut, the Climate Change Review author , warned, highly vulnerable to global warming.
Garnaut's 2008 Review estimated unmitigated warming would reduce economic production from irrigation in the Murray-Darling Basin by almost half before 2050. The FAO considers the basin, responsible for 40 per cent of our agricultural output, ''at risk''. The release of the draft basin plan this week met an outcry about the impact on food production of cuts in water availability of 2750 billion litres - a 25 per cent reduction on 2009 extraction levels.
The Australian Bureau of Agricultural and Resource Economics forecast the cuts would reduce the gross value of irrigated agriculture production by 9 per cent this decade, roughly a 4 per cent cut in the basin's total agricultural production (or less, as irrigators revert to dryland farming).
The draft basin plan does not allow for climate impacts on water availability that environment campaigners say is setting it up to fail. The Commonwealth Scientific and Industrial Research Organisation does not comment on why climate has been disregarded, except to note that the Murray-Darling Basin Authority has decided to rely on historical inflow sequences, reflecting a policy to ''initially accept the climate change risk sharing among users that is represented in current water sharing plans''. The since-ditched guide to the basin plan modelled scenarios from a 9 per cent increase in water availability to 2030, to a 27 per cent decrease, and opted for a 3 per cent cut in water availability.
Scenarios produced for 2030 by CSIRO and Bureau of Meteorology show 1 to 2 degrees of warming and rainfall changes in the Murray-Darling Basin of plus 5 per cent and minus 20 per cent. Dr Mark Howden, the chief research scientist of CSIRO's Climate Adaptation Flagship, says, for every per cent less average rainfall, river flow is reduced by two to three times, as a rule of thumb. So the CSIRO Murray-Darling Sustainable Yields study found that Murray River flows could change from an increase of 7 per cent to a decrease of 41 per cent by 2030.
The impact is likely to vary considerably across the basin, from north to south, Howden says. By 2030, the impact of climate change on the southern part of the basin could be similar to the ''millennium drought'', over and over again.
What will be the impact on food production? That depends in part on whether market mechanisms exist to allow farmers to trade water and switch to higher-value uses - earning more dollars per litre of water used - and on policy responses, adaptations to farm management, knowledge transfer and so on. It is not a linear relationship between water availability and food production. ''We're not passive receivers in this,'' Howden says. ''We're not disempowered in the face of change. We can do a lot to reduce the risks and increase the opportunities.''
But first we have to get past denial and be realistic about the problem. Howden's published and peer-reviewed research predicts Australia could, by 2050, be a net importer of wheat, our biggest agricultural export, due to the combination of high population growth and climate change. Australia became a net importer of fruit and vegetables during the millennium drought. ''This could already be a signal in terms of our ability to feed ourselves under a changed climate,'' Howden says, ''insofar as that drought has in it a fingerprint of climate change, as shown by the Bureau of Meteorology.
''Food security is often framed in the global sense, and because most Australians have access to enough food, we don't think about it as being on our own doorstep. But there are some early signs that it's already happening here.''
This month, an international body, the Commission on Sustainable Agriculture and Climate Change, including the CSIRO chief executive, Dr Megan Clark, published a report, ''Achieving food security in the face of climate change'', which threads together challenges from climate, population growth and affluence, food price spikes and land degradation. The recommendations are impossibly broad but some key facts highlight the problem: with a population of 7 billion, 1.5 billion over 20 are overweight while 0.9 billion are undernourished. About a third of all food production, or 1.3 billion tonnes a year, is wasted due to poor storage or lack of refrigeration in the developing world, or going off in fridges in the developed world.
The deputy director of the CSIRO's Sustainable Agriculture Flagship, Dr Peter Carberry, worked on the commission's report and says closing the gaps in farm yields, between developing and developed nations, is a challenge. ''Many places in the world only produce 10 per cent to 20 per cent of what's possible,'' he says.
Carberry recently travelled to West Africa, visiting farms in landlocked and impoverished Mali and Burkina Faso, and in trials of genetically-modified cotton has seen increases in yields of 30 per cent, while cutting pesticide use by 60 per cent.
Elsewhere, though, farm productivity gains are starting to taper off. Over the last 50 years, the world has lifted food supply by 180 per cent, while population has increased 120 per cent. But those gains came from increased resource use - more land, more labour, more energy, more water, more fertiliser and pesticide.
The challenge this century is to get more out of those resources, while cutting greenhouse gas emissions from agriculture and reducing other environmental externalities.
Carberry is confident Australia's farmers can continue to feed the country, despite climate change, by innovating and adapting. He points to the dry Mallee areas of north-west Victoria. During the drought, he says, ''they had nine years of below-average rainfall. This year's rain has been in the second decile [as occurs in the bottom 20 per cent of years]. Farmers in that region for the last 50 years have assumed they grew crops on in-season rainfall.
''In the wet summer, they would normally just grow summer weeds. This year they've stored water in soil, rather than let the weeds grow. Now in a drought year they've got this fantastic result.''
The picture isn't clear yet. A puzzling map of the world in 2080, in the commission's report, shows agricultural production falling by 50 per cent in much of northern and western Australia and rising by up to 35 per cent in New Zealand.
However imminent, threats to our food supply are much more concrete than the death of the Great Barrier Reef or the loss of Arctic summer sea ice.
Our food task may even be more important than the energy task. It's the old story, says Howden: ''Economists would say demand for food is 'quite inelastic'. Whereas demand for fuel or energy is actually somewhat elastic. Risking food security is one thing you don't muck around with.''
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