Projecting the World Economy to 2050: Agriculture in the Economy-wide GTAP Model

Recent analyses of the possible adverse effects of climate change and policy responses on agriculture and mining have raised food and energy security concerns in both rich and poorer countries. Analysing possible effects of ways of dealing with those concerns requires first projecting the world economy forward to 2050 and beyond. This paper provides as background a set of projections to 2050, drawing on the global economy-wide model known as GTAP. The projection is calibrated to ensure the real prices of primary products remain broadly unchanged from their levels in the model's base year of 2004. Alternative scenarios could have been calibrated to show (a) rising real prices for both food and energy raw materials (consistent with forecasts of several international agencies), by assuming some slowdown in productivity growth in primary sectors, or (b) declining real prices for agricultural and mining products (consistent with the experience of most of the 20th century), by assuming somewhat faster productivity growth in primary sectors. The set of projections shown for 2030 and 2050 is thus an intermediate set. The key impacts on international prices, agricultural self-sufficiency, sectoral shares of national economies and national shares of the global economy are highlighted. The paper concludes with implications for R&D spending and research policy.