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Thomas Hertel – 2013 Purdue University Research and Scholarship Distinction Award
Global Change and the Challenges of Sustainably Feeding a Growing Planet
Thomas W. Hertel, Distinguished Professor of Agricultural Economics
Over the past decade, there has been a resurgence of interest in global agriculture, and feeding the world’s population while simultaneously improving environmental quality. Looking forward, analysis suggests that population and income will remain the two most important drivers of change in the global food system. However, their relative importance will be altered, with the income eclipsing the population for the first time in the world’s history. When coupled with potential increases in biofuel production, this suggests the need to double crop production by mid-century. So a critical challenge is whether this can be accomplished through sustainable intensification. Repeating the yield growth experience of the past fifty years will require significant investments in agricultural research. However, these challenges notwithstanding, and contrary to popular consensus, the lecture will present evidence suggesting that the most likely long run outcome will be a resumption of the downward trend in real crop prices that has characterized the past century.
Over the past decade, there has been a resurgence of interest in the world’s food system and its contributions to feeding the world’s population, while at the same time ensuring environmental sustainability. This lecture presents new evidence on the long run forces shaping this ‘grand challenge’, as well as projections for the century ahead.
A now familiar refrain is that the world must feed an additional two billion people by 2050. While daunting, the rate of growth in the world’s population is slowing. Meanwhile, per capita incomes are growing strongly in many parts of the developing world, leading to significant nutritional improvements for the 2.1 billion people living on less than $2/day. The ensuing demands for richer, more ample diets will increase pressure on global croplands. Our prospective analysis suggests that, while population and income will remain the two most important drivers of change in the global food system, their relative importance will be altered, with the income eclipsing population for the first time in the world’s history.
Biofuel production has recently presented a rapidly growing source of demand for agricultural output. This has brought with it a new source of uncertainty for agriculture – namely energy prices and associated policies. Under a high fossil fuel price scenario in which second generation biofuels are aggressively deployed to combat climate change, we find that their expansion could account for nearly half of the increase in global land use over the next few decades. On the other hand, if today’s flat oil and gas price trajectories persist, this will erode commercial and policy interest in biofuels, while also lowering the cost of intensification, both of which will contribute to lessening pressure on global croplands – potentially lowering the demand for global cropland by 400 million hectares by 2100.
Even in the absence of biofuel expansion, the world will likely need to double crop production by mid-century. This can occur either through intensification (increased yields) or area expansion. Remarkably, nearly all of the growth in output over the last half of the 20th century occurred through intensification. However, there are signs of slowing yield growth for key staple crops – a phenomenon which may be reinforced in future by rising temperatures in the wake of climate change. To compound matters, water, a key input into irrigated agricultural production, is becoming increasingly scarce in many key regions. This suggests heightened pressures to expand cropland. Unfortunately, conversion of new croplands flies in the face of climate policies aimed at preserving forest and soil carbon stocks, as well as attempts to preserve biodiversity.
All of this points to the critical role for sustainable intensification of agricultural production over the next four decades, which is a critical window for global agriculture. Given the long lag time between investments in agricultural research and improved yields, what the world does in the next decade will likely determine how successful we are in sustainably feeding the planet in 2050.
In light of the analysis presented in this lecture, and noting the great uncertainty in the long run drivers of global agriculture, the lecture concludes that, contrary to apparent popular consensus of a ‘new normal’ in world agricultural markets, the most likely long run outcome will be a resumption of the downward trend in real crop prices that has characterized the past century.
Thomas Hertel is Distinguished Professor of Agricultural Economics at Purdue University, where his research focuses on the impacts of global trade and environmental policies. Hertel is a Fellow, and Past-President, of the Agricultural and Applied Economics Association (AAEA). He is also Founder of the Global Trade Analysis Project (GTAP) which now encompassing 10,000 researchers in 150 countries. GTAP maintains global economic data base and quantitative frameworks for analysis of global trade and environmental issues.
Hertel’s most recent research has focused on the impacts of climate change and mitigation policies on global land use and poverty. Previously, he has conducted extensive research on the impacts of multilateral trade agreements, including the linkages between global trade policies and poverty in developing countries which won the AAEA award for Quality of Communication. Other AAEA awards include: Distinguished Policy Contribution and Outstanding Journal Article. Hertel has also chaired three dozen PhD committees during his tenure at Purdue.