NLC-下一次美国移民：城市应该了解哪些气候变化和人口流动（英）-2022.4-47页_41mb

Summary of "What Cities Should Know About Climate Change and Populations on the Move"

Core Content

This report from the National League of Cities (NLC) and Buy-In Community Planning, Inc. explores the growing phenomenon of climate migration in the United States and its implications for cities. It emphasizes the need for local governments to understand and prepare for the impacts of climate change on population movements, both internal and external, and the resulting demographic and economic shifts.

Main Points

• Climate migration is a complex and multifaceted issue, involving both slow onset and sudden onset events.
• Slow onset events (e.g., droughts, sea level rise, extreme heat) may lead to gradual displacement, while sudden onset events (e.g., wildfires, hurricanes, floods) can result in immediate, sometimes permanent, relocation.
• Disproportionate impacts are common among vulnerable populations, including low-income households, renters, Black communities, immigrant populations, and indigenous communities. These groups often reside in high-risk areas due to historical disinvestment and discriminatory policies.
• Climate change is increasingly influencing demographic trends, with many Americans moving to areas that are less risky or more resilient, even as others remain in high-risk zones due to economic, social, or cultural constraints.
• Federal, state, and local policies play a key role in shaping migration patterns, including building codes, insurance rates, land use planning, and housing availability.
• Data and demographic models are being used to project future migration trends, but local officials and residents remain the primary experts on the cultural, historical, and political aspects of their communities.
• Cities and states are beginning to incorporate climate migration into their planning, such as LA SAFE in Louisiana and Blue Acres in New Jersey, which offer models for relocation and disaster response.
• Climate resilience is not only about reducing risk but also about ensuring equitable outcomes and sustainable growth for all residents, regardless of their net population gain or loss.

Key Information

• Climate migration is a growing concern, with over 1.7 million Americans displaced by disasters in 2020.
• Sea level rise threatens 40% of the U.S. population, particularly in coastal areas, and could significantly reshape the U.S. population landscape.
• Extreme heat is the leading cause of weather-related deaths, and by 2050, 4-6 times more people could be exposed to it.
• Flood risk is projected to affect nearly 2.5 million properties by the end of the 21st century, with an estimated $1.07 trillion in value.
• Displacement is not just physical; it has social, economic, and political ramifications, including gentrification, housing shortages, and increased inequality.
• Climate-based decisions are influencing housing and relocation choices, though perceptions and responses vary by region, age, education, and political affiliation.
• Federal and state-level preemption laws may limit the ability of local governments to implement climate resilience measures, especially in states that are most vulnerable to climate impacts.

Framework for Understanding Climate Migration

The report introduces a simple framework to categorize cities based on their role in climate migration:

1. Vulnerable cities: Those most at risk from climate impacts.
2. Recipient cities: Cities that may receive displaced residents.
3. Climate destinations: Cities that are becoming more attractive due to climate resilience or other factors.

This framework is intended to inspire local conversations and inform policy decisions, but it is not prescriptive. It is up to local leaders to determine which characteristics apply to their community.

Recommendations

• All cities should begin integrating climate migration into their planning and policy-making processes.
• Vulnerable cities should focus on resilience-building and risk reduction.
• Recipient cities should prepare for increased demand for housing and services.
• Climate destinations should leverage their strengths to attract and support incoming populations.
• States and federal agencies should develop better policy solutions and improve funding mechanisms to address the inequities in climate migration.

Conclusion

The report underscores that climate migration is already shaping the U.S. and that cities must be proactive in planning for both the risks and opportunities it presents. It highlights the importance of data, community engagement, and equitable policy in addressing this growing challenge.

Appendix and References

• The report includes an appendix with additional details and a list of endnotes citing the sources of all data and information.
• It references geospatial data tools such as FEMA's National Risk Index and the 4th National Climate Assessment to help cities understand their local risks.
• Case studies from cities like Charleston, SC, Orlando, FL, Chico, CA, Ann Arbor, MI, Flagstaff, AZ, and Cincinnati, OH provide real-world examples of how different cities are responding to climate migration.

This report serves as a guide for local leaders to understand and prepare for the impacts of climate change on population movements and to build more resilient, equitable, and sustainable communities.