2013年-世界发展银行全球_Climate_Change_and_Agriculture___A_Review_of_Impacts_and_Adaptations_106页_875kb

Climate Change and Agriculture: A Review of Impacts and Adaptations

Core Content

This paper reviews the impacts of climate change on agriculture and the adaptation strategies that can be employed to mitigate these effects. It is authored by Pradeep Kurukulasuriya and Shane Rosenthal, doctoral students at Yale University, and published by the World Bank in June 2003. The review is conducted jointly by the Environment Department and the Agriculture and Rural Development Department of the World Bank.

Main Viewpoints

• Climate Change and Agriculture Vulnerability: The agricultural sector is highly vulnerable to both climate change and variability. Changes in temperature and precipitation can alter land and water regimes, which in turn affect agricultural productivity. Tropical regions, especially those with poor countries, are expected to face particularly harmful impacts.

• Adaptation as a Key Strategy: Adaptation is recognized as a crucial mechanism for reducing the adverse effects of climate change. It is considered a pragmatic and necessary approach alongside mitigation efforts, especially in developing countries with limited resources and institutional capacity.

• Diverse Adaptation Options: There is no one-size-fits-all solution for adaptation. The paper outlines various adaptation strategies, both short-term and long-term, that can be implemented at the micro and macro levels. These include changes in crop type and location, improvements in water management, and the adoption of new technologies.

• Economic and Social Impacts: Climate change is expected to reduce agricultural yields in many developing countries, leading to increased poverty levels. In contrast, temperate regions may benefit from longer growing seasons and enhanced carbon fertilization effects.

• Need for Integrated Policies: The paper emphasizes the importance of integrating adaptation into broader policies on poverty reduction and sustainable development. It also highlights the necessity of interdisciplinary approaches to address climate change impacts effectively.

Key Information

• Impacts of Climate Change: Climate change is projected to affect agricultural productivity through changes in land and water regimes, extreme weather events, and resource shortages. These impacts are expected to be more pronounced in tropical regions.

• Adaptation Mechanisms: Adaptation can be categorized into short-term and long-term strategies. Short-term adaptations include farm responses, temporary migration, and insurance. Long-term adaptations involve changes in crop type and location, technological modernization, and institutional reforms.

• Economic Consequences: Without adaptation, global agricultural welfare could suffer losses of up to US$61.2 billion. With appropriate adaptations, these losses could be reduced to a range of US$37 billion to gains of US$70 billion. In developing countries, climate change could reduce agricultural production by 14-16 percent.

• Regional Variations: The impacts of climate change on agriculture are expected to vary significantly across regions. For example, in Africa, the agricultural sector contributes up to 34 percent to GDP, and nearly 60-70 percent of the population depends on it for employment.

• Role of CO₂ Fertilization: Increased carbon dioxide levels are expected to enhance photosynthesis and water use efficiency, potentially improving agricultural productivity. However, these benefits may be offset by increased pest and weed infestations.

• Importance of Policy Integration: The paper calls for the inclusion of adaptation measures in poverty reduction and sustainable development policies. It suggests that "no-regrets" adaptation options should be promoted through an interdisciplinary approach.

Typology of Adaptations

• Short-Term Adaptations:

  • Farm Responses: Adjusting planting times, crop varieties, and irrigation practices.
  • Temporary Migration: Moving agricultural activities to more favorable areas temporarily.
  • Insurance: Using insurance mechanisms to manage climate-related risks.

• Long-Term Adaptations:

  • Changing Crop Type and Location: Shifting to more resilient crops and relocating agricultural activities.
  • Technological Modernization: Adoption of new technologies to improve productivity and resilience.
  • Water Management: Enhancing irrigation systems and managing water resources more efficiently.
  • Permanent Migration of Labor: Moving out of agriculture permanently in response to long-term climate pressures.

• Adaptations Independent of Time Dimension:

  • Investment and Capital Accumulation
  • Reform of Pricing Schemes and Open Markets
  • Adoption of New Technologies
  • Promotion of Trade
  • Extension Services
  • Diversification of Income Sources
  • Dissemination of Climate Data
  • Institutional Planning and Implementation

Conclusion

The review concludes that adaptation is essential for reducing the vulnerability of the agricultural sector to climate change. Policymakers should focus on developing and implementing adaptive strategies that reflect current and future climate conditions. Dynamic adaptation is necessary, as no single solution will suffice for all time. Incentives that promote adaptation should be integrated into broader development policies to enhance the resilience of the agricultural sector and support sustainable development.