2017年-世界发展银行全球_Economic_Growth_Convergence_and_World_Food_Demand_and_Supply_47页_1mb

Summary: Economic Growth, Convergence, and World Food Demand and Supply

Core Content

This paper explores the future trajectory of global food demand and supply up to 2050, emphasizing the role of income growth and convergence in shaping these trends. It challenges the conventional focus on population growth as the main driver of food demand, arguing that per capita demand growth, particularly due to income convergence, will play a more significant role in determining future food demand.

Main Points

• Population Growth vs. Income Growth: While population growth is expected to increase from 7.4 billion in 2017 to over 9 billion by 2050, the impact of income growth on food demand is becoming more important. As incomes rise, the proportion of income spent on food declines, but the growth in food demand is likely to be greater if developing countries experience faster income growth than high-income countries.

• Income Convergence: Income convergence refers to the trend where low- and middle-income countries grow faster than high-income countries. This convergence is expected to significantly increase global food demand, with projections showing that food demand could rise by 102% by 2050 under convergence scenarios, compared to 78% without it.

• Dietary Changes and Resource Requirements: As incomes rise, diets in developing countries are shifting from starchy staples to more diversified diets, including animal-based products. This dietary upgrading increases the resource requirements for food production, particularly in terms of land use and agricultural output, which has implications for food prices and supply.

• Cereal Equivalents (CE) as a Measure: The paper uses cereal equivalents (CE) to quantify food demand, which accounts for the resource costs of producing different types of food. This approach reflects the increasing importance of animal-based products in diets and their higher agricultural resource demands.

• Modeling Approach: The authors extend a simple econometric model developed by Fukase and Martin (2016) to the global level. The model incorporates income elasticity of food demand and uses projections from the Shared Socioeconomic Pathways (SSP) database, particularly the middle-ground scenario (SSP2), to estimate future food demand and supply.

• Impact on Food Prices: Income convergence is expected to increase food demand more than it increases food supply, leading to upward pressure on global food prices. This effect is partially offset by the baseline trend of falling food prices due to technological progress and efficiency gains.

• Regional Analysis: The paper highlights regional differences in food consumption patterns and income growth. For example, China's rapid economic growth has driven significant increases in CE consumption, while regions like South Asia and Sub-Saharan Africa are expected to see substantial population growth and increased food demand.

• Income Elasticity Patterns: The income elasticity of food demand follows an inverted-U shape. At low income levels, the elasticity is relatively low, but it increases as countries move toward middle-income levels, peaking at around 0.42 when PPP GDP is about $10,000. After that, the elasticity declines as income continues to rise.

• Comparison with Other Projections: The paper's projection of a 102% increase in global CE food consumption by 2050 is higher than estimates from the FAO (70%) and Pardey et al. (69%), but aligns with Tilman et al.'s (2011) projection of a 100-110% increase in food demand, considering both caloric and protein content.

Key Findings

• Income Convergence: Income convergence has become a key factor in food demand growth, with developing countries growing faster than high-income countries. This trend has important implications for global food demand and supply dynamics.

• Dietary Upgrading: As incomes rise, especially in developing countries, diets are becoming more diversified, with increased consumption of animal-based products. This shift increases the demand for agricultural resources, which may affect food prices and supply.

• Modeling Insights: The use of a resource-based measure (CE) and the incorporation of income elasticity into the model provide a more accurate representation of food demand patterns. The model shows that per capita income growth is becoming a more important driver of food demand than population growth.

• Future Projections: Under the middle-ground scenario (SSP2), global food demand is projected to grow by 102% by 2050, driven by both population growth and per capita consumption growth. However, per capita consumption growth is expected to be the dominant factor, contributing about 60% of the total increase.

• Policy Implications: The findings suggest that income convergence and dietary upgrading are critical for understanding future food demand. These trends have implications for food security, trade, and global food price stability, especially for low-income populations.

Conclusion

The paper concludes that income convergence and per capita demand growth, rather than population growth alone, are likely to be the dominant forces driving global food demand up to 2050. The shift toward more resource-intensive diets in developing countries will increase the pressure on food supply and may lead to higher global food prices, which could affect food access for the poor. Understanding these dynamics is essential for developing effective policies to ensure food security and support sustainable development.