North Coast Region- California Climate Adaptation Strategy

Background

The North Coast region encompasses Mendocino, Humboldt, Del Norte, Lake, Trinity, and Siskiyou Counties. It is characterized by its rugged coast, Humboldt Bay and lagoons, redwood forests, rivers, and iconic salmon and steelhead. Comprised of small to medium-sized communities with ~372,000 residents, the region is the top producer of timber in the state, and is also supported by the cannabis industry and tourism.

Extreme Heat

Average annual maximum temperatures are projected to increase by 5–9°F in the region by 2100. Interior areas of the North Coast will experience the greatest degree of warming. Winter season temperatures are expected to warm by a greater magnitude to those of other seasons, with a 5–7°F increase by mid-century and 8–11°F increase by end-of-century.

Drought and Flood

Variability in precipitation is projected to increase with a higher likelihood of extreme wet and extreme dry years. River stream flows are projected to decline in dry seasons and increase in wet seasons. Oscillation from dry to wet conditions and shortened wet seasons will cause total snowpack to decrease from historical averages.

Wildfire

Future wildfire projections suggest a longer fire season, an increase in wildfire frequency, and an expansion of the area susceptible to fire. Increases in average temperature and frequency, duration, and severity of heat waves will also add to the extension of the fire season, especially in sites with variable and decreasing snowpack.

Sea Level Rise

Sea level rise projections in the North Coast range widely due to geologic activity within the region. Projections along the southern portion of the region (Humboldt Bay) estimate between 2.4–3.9 feet of sea level rise by 2100, with slim potential for a rise as high as 7.3 feet. In contrast, due to tectonic uplift, the northern portion of this region (Crescent City) has lower projected rates of 0.8–2.3 feet by 2100, with slim potential for a rise as high as 5.6 feet.

More on this Region

Regional Report in California's Fourth Climate Change Assessment

Climate Resilience Resources & Case Studies in California’s Adaptation Clearinghouse

Region North Coast