2022-03-01-联合国-2022年气候变化影响_适应和脆弱性_37页_10mb

Summary for Policymakers: Climate Change 2022 - Impacts, Adaptation and Vulnerability

Core Content

This Summary for Policymakers (SPM) presents key findings from the Working Group II (WGII) contribution to the Sixth Assessment Report (AR6) of the Intergovernmental Panel on Climate Change (IPCC). It emphasizes the interconnectedness of climate, ecosystems, and human societies and integrates knowledge across natural, ecological, social, and economic sciences. The report also highlights the importance of adaptation, resilience, and climate-resilient development in addressing climate risks and supporting sustainable development.

Main Views and Key Findings

Climate Change and Its Impacts

• Observed Impacts: Human-induced climate change has caused widespread adverse effects on ecosystems, people, and infrastructure, including increased frequency and intensity of extreme weather events.
• Irreversible Impacts: Some impacts, such as coral bleaching and species extinctions, are already irreversible, and others are approaching irreversibility.
• Global and Regional Effects: Impacts are observed globally and regionally, with significant effects on water and food security, health, and economic systems.
• Adverse Effects on Vulnerable Groups: Indigenous Peoples, small-scale food producers, and low-income households are disproportionately affected, especially in Africa, Asia, Central and South America, Small Islands, and the Arctic.

Risks and Vulnerability

• Climate Risks: Risks arise from the interaction of climate hazards, exposure, and vulnerability. The report identifies 127 key risks.
• Vulnerability: Vulnerability varies across communities, regions, and over time, and is influenced by socioeconomic factors.
• Complex and Compound Risks: These occur when multiple climate hazards interact or when they occur simultaneously, increasing overall risk.

Adaptation and Resilience

• Adaptation: Adaptation in human systems can be anticipatory, reactive, incremental, or transformational. It plays a key role in reducing exposure and vulnerability.
• Limits to Adaptation: Adaptation is constrained by both hard and soft limits, including economic, technological, and institutional barriers.
• Avoiding Maladaptation: The report stresses the need to avoid maladaptation, which can lead to increased risks and losses.
• Resilience: Resilience is not just about returning to a previous state but also includes the capacity for transformation.

Climate Resilient Development

• Definition: Climate resilient development is the process of implementing mitigation and adaptation together to support sustainable development.
• Enabling Conditions: This includes governance, finance, knowledge, capacity building, technology, and catalysing conditions.
• System Transitions: The report focuses on system transitions in energy, land, ocean, urban, rural, and industrial sectors to achieve resilience and sustainability.
• Climate Justice: The report incorporates principles of distributive, procedural, and recognition justice in the context of climate adaptation and mitigation.

Key Information

• Climate Change Trends: The global surface temperature has increased by 1.09°C (0.95 to 1.20°C) above pre-industrial levels (1850-1900) in 2011-2020.
• Global Warming Levels: The report uses global warming levels (e.g., 1.5°C) and reference periods (e.g., 2021-2040, 2041-2060, 2081-2100) to assess climate impacts and risks.
• Climate Models: Projections are based on climate model simulations from the CMIP5 and CMIP6 projects, as well as Representative Concentration Pathways (RCPs) and Shared Socio-economic Pathways (SSPs).
• Observed Impacts: These include heat-related mortality, coral bleaching, increased tree mortality due to drought, and impacts from tropical cyclones, sea level rise, and heavy precipitation.
• Economic Impacts: Climate change has had both adverse and positive economic effects, with significant losses in agriculture, fisheries, energy, and tourism, and some benefits in energy demand and tourism.
• Health Impacts: Physical and mental health are adversely affected, with increased risks of diseases and disruptions in health services.

Structure of the Report

• SPM.A: Introduction – Overview of the report, its context, and its key focus areas.
• SPM.B: Observed and Projected Impacts and Risks – Detailed analysis of observed and projected impacts, including climate hazards, ecosystem and human system responses, and regional and global effects.
• SPM.C: Adaptation Measures and Enabling Conditions – Discussion of current and future adaptation options, limits to adaptation, and enabling conditions for effective adaptation.
• SPM.D: Climate Resilient Development – Focus on achieving climate resilient development through system transitions, governance, finance, and technology.

Conclusion

The report underscores the urgent need for adaptation and transformation to reduce climate risks and support sustainable development. It calls for integrated, equitable, and inclusive approaches to climate resilience, emphasizing the role of diverse knowledge systems and the importance of climate justice in shaping future responses.