Vulnerability of recreation, infrastructure, and ecosystem services to climate change in southern California.

Abstract

The Southern California Adaptation Partnership identified climate change issues relevant for resource management on national forest and national park units in southern California. This partnership assessed the vulnerability of infrastructure, outdoor recreation, and ecosystem services to climate change and developed adaptation options that minimize negative effects of climate change and facilitate transition to a warmer climate.

High levels of use and aging roads and facilities on federal lands are increasing the vulnerability of infrastructure to the effects of climate change. Altered timing and amount of precipitation will likely create challenges when storing and allocating water for municipal water supplies, flood prevention, and recreation. Roads, bridges, and culverts are susceptible to increased runoff during storm events, causing failures. Increased magnitude of peak streamflows is expected to damage roads near perennial streams, especially following wildfires. Associated infrastructure, such as bridges, culverts, campgrounds, and facilities near streams and floodplains, will likely be particularly vulnerable. At vulnerable or flood-prone sites, resilience near stream crossings and in floodplains can be enhanced by designing infrastructure to withstand more frequent and severe flooding and upsizing or upgrading existing infrastructure to withstand future flooding. Some roads and other infrastructure can be decommissioned or moved to mitigate risks.

Nearly all recreation is affected by weather conditions, influencing decisions about if, when, and where to recreate. Warm-weather recreation will likely benefit from a longer period without cold weather and snow, especially during the spring and autumn shoulder seasons. Winter recreation (skiing, snowmobiling) will likely be negatively affected by a warmer climate because of less and more transient snow. The effects of higher temperatures on hunting, fishing, water-based recreation, and gathering forest products may be variable and less certain.

Adaptation strategies for recreation include adjusting staffing and management to accommodate changes in seasonal access and recreation locations, and increasing resilience of recreation sites to changing conditions or higher demand.

Several ecosystem services are considered in the assessment: water resources; livestock grazing; carbon sequestration; air quality and pollution abatement; soil regulation; biodiversity and genetic diversity; and cultural, traditional, spiritual, and heritage values. Reduced water supply is one of the biggest potential effects of climate change, given demand by the large population of southern California. Conservation of urban and agricultural consumption of water is the best adaptation strategy for maintaining water supply.

Citation

Halofsky, Jessica. E.; Peterson, David. L.; Buluç, Lara Y., eds. 2026. Vulnerability of recreation, infrastructure, and ecosystem services to climate change in southern California. Gen. Tech. Rep. PSW-GTR-281. Albany, CA: U.S. Department of Agriculture, Forest Service, Pacific Southwest Research Station. 288 p. https://doi.org/10.2737/psw-gtr-281.