Land-Use Changes and CO2 Emissions Due to US Corn Ethanol Production Table Simulated global land-use changes due to US ethanol production: off the updated baseline Changes in US corn ethanol production Land-use changes (ha) Within USA Other regions World Within USA Other regions World 3.085 BG 2.145 BG 2.000 BG 2.000 BG 2.000 BG 2.000 BG 13.23 BG 106,870 77,989 73,308 73,754 74,717 75,731 482,368 360,397 246,464 233,222 233,992 238,378 242,685 1,555,137 467,268 324,452 306,529 307,746 313,094 318,416 2,037,506 22.9 24.0 23.9 24.0 23.9 23.8 23.7 77.1 76.0 76.1 76.0 76.1 76.2 76.3 100.0 100.0 100.0 100.0 100.0 100.0 100.0 Table (2001–2006) (2006–7 BG) (7–9 BG) (9–11 BG) (11–13 BG) (13–15 BG) (2001–15 BG) a Distribution of land-use changes (%) Hectares per 1000 gallons 0.15 0.15 0.15 0.15 0.16 0.16 0.15 Simulated global land-use changes due to US ethanol production: off the updated baseline Changes in US corn ethanol output 3.085 BG 2.145 BG 2.000 BG 2.000 BG 2.000 BG 2.000 BG 13.23 BG 547 (2001–2006) (2006–7 BG) (7–9 BG) (9–11 BG) (11–13 BG) (13–15 BG) (2001–15 BG) Land-use changes (ha) Distribution of land-use changes (%) a Forest Grassland Crop À 151,706 À 105,357 À 99,673 À 100,005 À 101,633 À 103,423 À 661,797 À 315,487 À 219,095 À 206,854 À 207,740 À 211,466 À 214,992 À 1,375,633 467,268 324,452 306,529 307,746 313,094 318,416 2,037,506 Forest 32.5 32.5 32.5 32.5 32.5 32.5 32.5 Grassland 67.5 67.5 67.5 67.5 67.5 67.5 67.5 Totala 100.0 100.0 100.0 100.0 100.0 100.0 100.0 The difference between the changes in cropland and the sum of forest and grassland is due to rounding Table represents distributions of land-use changes between forest and pasture for the second group of simulations In this group of simulations, on average about 33% of required land for ethanol production comes from forest land This figure is higher than the corresponding figure of the first group of simulations (25%) Group 3: Simulations with Crop Yield and Population Growth for the Time Period 2006–2015 Some advocates of the US corn ethanol program argue that crop yields will increase in the future such that this increase could eliminate the land-use implications of ethanol production This argument neglects the impacts of the future changes in the demand for crops Demands for crops could increase in the future due to several factors such as changes in population and income, dietary transition as poorer countries consume more meat, or technological progress In other words, one cannot examine yield (supply) increases alone One must also include assumptions about increases in crop demand as well In the third group of simulations, impacts of changes in crop yields and demand are examined as important items that could determine demand and supply for crops and food products In the third group of simulations, population growth is introduced into the model as a proxy for food demand increase It is assumed that population will continue to grow globally during the time period 2006–2015 at the annual growth rate of 2001–2006 It is also assumed that crop yield will increase uniformly at 1% annually after 2006 in all regions and across all types of crops Although 1% might seem small, it is actually a large number as it is applied in all regions and for all crops Finally, it is assumed that the regional demands for forest products will increase according to their annual rates of 2001–2006 The latter assumption is made to maintain the long-run pattern in the outputs of forest products These simulations also include all the changes incorporated in the baseline simulation of the second group of simulations To find the land-use impacts of the US ethanol program under these assumptions, simulations were done with and without US ethanol production off the 2006 updated database (obtained in the second group of simulations) for the time period 2006–2015 To understand the land-use implications of the US ethanol program under these assumptions, the landuse implications were first analyzed with no US ethanol production Table indicates land-use changes due to the yield and population growth for USA, EU, Brazil, and other regions This table indicates that after 2006, the cropland areas of USA, EU, Brazil, and other regions would fall due to the simultaneous shocks in yield and population growth This means that yield growth would dominate the demand growth for crops, and therefore the demand for cropland decreases everywhere In addition to that, the yield growth contributes to higher levels of food consumption everywhere The simulation results indicate that consumption of crops and food products grow faster than population everywhere across the world This indicates that the yield effect works through two channels: (1) reduction in crop land area needed