Summary

• Climate models project more frequent extreme rainfall from rare Eastern Pacific tropical cyclones affecting Southern California.
• Landslide-exposed area is projected to increase across all Southern California counties between 2000 and 2050.
• Low-income households are already more exposed to landslide-prone areas, and that disparity is expected to widen.
• Wildfires can remove vegetation and weaken slopes before later heavy rain triggers debris flows and landslides.
• Palos Verdes is experiencing worsening movement, damaged homes and utility disruptions after repeated heavy storms.
• El Niño and unusually warm Eastern Pacific waters may increase the likelihood of rare tropical cyclone rainfall impacts, although event probabilities remain uncertain.
• Local responses include forecasting, zoning, home protection, stabilization spending, buyouts and possible managed retreat.