2017年-世界发展银行全球_Climate_Change_and_Disaster_Management_136页_3mb

Summary of "Climate Change and Disaster Management" (Pacific Possible Background Paper No.6)

Core Content

This document explores the challenges and opportunities for climate change and disaster risk management in Pacific Island Countries (PICs). It emphasizes the need for resilient development strategies that take into account the region's vulnerability to climate change and natural hazards, such as cyclones, sea level rise, and flooding. The report is part of the Pacific Possible series, which focuses on transformative opportunities for the Pacific region over the next 25 years.

Main Points

1. Current and Projected Climate Risks

• Exposure to Natural Hazards: PICs are highly exposed to natural hazards, including cyclones, droughts, floods, and sea level rise.
• Climate Change Impacts: Rising temperatures, increased rainfall variability, and more intense tropical cyclones are expected. Sea level rise threatens the very existence of low-lying atoll nations like Kiribati, Tuvalu, and the Republic of the Marshall Islands.
• Poverty and Gender Vulnerability: The poorest populations, mainly in Kiribati, Vanuatu, and the Federated States of Micronesia (FSM), are especially vulnerable. Women are more affected due to their reliance on natural resources and exposure to gender-based violence post-disaster.

2. Managing Climate and Disaster Risks

• Adaptation Strategies: To manage risks, five key decision frameworks are recommended:
  1. No-regret strategies: Actions that yield benefits regardless of climate change, such as improving water distribution systems or building to higher standards.
  2. Reversible and flexible options: Such as insurance, early warning systems, or adaptable coastal defences.
  3. Safety margins: Incorporating higher standards into new investments.
  4. Institutional and policy reforms: Including multi-criteria assessments and long-term planning.
  5. Reducing decision time horizons: Designing infrastructure with shorter lifespans for cost efficiency.

3. Sector-Specific Adaptation

Coastal Protection

• Adaptation Costs: Coastal protection will be the most expensive adaptation measure by 2040.
• Cost Range: Costs vary significantly between countries. For example, in the Solomon Islands, costs could be as high as USD 97 million per year (3% of GDP), while in Palau, they could be as low as USD 3 million per year (1% of GDP).
• Key Costs: Over 75% of the costs are for construction and maintenance of sea walls.
• Recommendations: Flexibility in design, combining hard and soft options, and relocating populations away from vulnerable coastal areas.

Flood and Water Resource Management

• Rainfall Patterns: Increased rainfall intensity and variability are expected, with some countries like Fiji and FSM seeing significant increases.
• Adaptation Measures: Improved water storage, rainwater harvesting, and better drainage systems are critical.
• Costs: For most PICs, adaptation costs for infrastructure against changes in rainfall and temperature range from 2% to 20% of baseline expenditures.

Infrastructure Adaptation

• Infrastructure Vulnerability: All types of infrastructure (roads, hospitals, schools, housing) are at risk from climate change.
• Adaptation Costs: The cost of protecting infrastructure varies, with roads accounting for over 50% of the average costs in most PICs.
• Strategies: Prioritizing pre-emptive measures and improving maintenance standards. For some PICs, reactive measures such as rebuilding roads after damage may be more cost-effective.

Building Resilience to Cyclone Winds

• Building Standards: Ensuring new buildings can withstand 1 in 50 year cyclone wind speeds is crucial.
• Retrofitting Benefits: Retrofitting existing buildings can reduce expected losses by 35–50%.
• Cost Efficiency: Retrofitting is more cost-effective in countries with higher cyclone risks, such as Vanuatu, Fiji, and Samoa.

Agricultural Adaptation

• Climate Impacts: Increased temperatures and seasonal droughts are expected to reduce crop yields, especially for cassava, maize, and taro.
• Adaptation Needs: Both low-cost no-regret options (mulching, multiple cropping, improved farmer education) and long-term investments (climate-smart crop varieties, insurance mechanisms) are needed.
• Potential Economic Impact: By 2100, the impact on GDP could be strongly negative, equivalent to 5% of Pacific GDP, due to declining crop yields.

4. Special Case: Atoll Islands

• Vulnerability: Atoll nations like Kiribati, Marshall Islands, and Tuvalu are at risk of losing land and becoming uninhabitable due to sea level rise.
• Land Loss Projections: A 50cm rise in sea level could lead to the disappearance of 80% of land in the Republic of the Marshall Islands.
• Costs: Coastal adaptation costs in Kiribati could reach USD 17–54 million annually (4–11% of GDP), requiring international financial support.
• Challenges: Limited financial resources and land scarcity make adaptation difficult. Reclaiming land or raising atolls may be necessary, but these are complex and costly.

Key Information

• High Adaptation Costs: PICs face significantly higher adaptation costs compared to other regions, with some countries allocating up to 13% of GDP for coastal protection.
• Uncertainty in Climate Projections: Climate change impacts are highly uncertain, especially at local levels, making long-term planning difficult.
• Need for International Support: Given the financial constraints of PICs, international assistance will be essential for large-scale adaptation efforts.
• Institutional Capacity: Strengthening institutional frameworks for integrated coastal and disaster management is a critical component of adaptation strategies.
• Regional Variability: Adaptation strategies must be tailored to the specific needs and conditions of each PIC, as the impacts and costs vary significantly.

Conclusion

The report underscores the importance of proactive and flexible adaptation strategies to address the growing risks from climate change and natural disasters in PICs. It highlights the need for collaboration between PICs and the international community, as well as the necessity of improving institutional capacity and integrating climate resilience into development planning. The focus is on cost-effective, no-regret options and the development of long-term, sustainable solutions tailored to the unique challenges of each country.