IMF-物理气候风险对全球经济的影响（英）-2023.9-125页_8mb

The IMF Working Paper WP/23/183 examines the global economic consequences of physical climate risks under two Shared Socioeconomic Pathways (SSP 1-2.6 and SSP 2-4.5).

Key findings:

1. Methodology: It employs a novel approach, using a global sample of 59,554 firms to estimate sectoral productivity impacts due to both chronic climate risks (temperature/precipitation changes) and extreme climate events (heatwaves, coldwaves, droughts, floods). These impacts are fed into a global, multisectoral, intertemporal general equilibrium model called G-Cubed.
2. Sectoral Impacts:
   • Agriculture is most vulnerable, with productivity reductions of 10-20% in many regions by 2100.
   • Mining experiences significant losses, exceeding 5% in certain regions.
   • Manufacturing and services are less affected due to greater flexibility in locating operations.
3. Macroeconomic Consequences:
   • Climate risks cause substantial economic losses.
   • Under SSP 1-2.6 (lower emissions), global GDP loses about 1.2% of annual averages by 2100, rising to over 3.2% under SSP 2-4.5 (intermediate emissions). Countries like Canada and Russia experience the highest losses in both scenarios.
   • These impacts ripple through the economy, significantly reducing consumption, investment, imports, exports, and affecting real interest rates, exchange rates, and trade balances.
4. Extreme Events: Flood damage causes persistent productivity declines, unevenly distributed globally, especially in Asia and Africa.
5. Robustness: The results align with previous studies on broadly the same order of magnitude, ranging widely due to differing methodologies.

Policy Implication: Policymakers are urged to recognize the high cost of inaction on climate change adaptation. Emphasis is placed on the need for strengthening adaptation strategies to mitigate widespread economic losses expected under future warming scenarios, while acknowledging the limitations of current approaches. The paper calls for better resilience to physical climate risks.