Sierra Nevada summary report. California’s Fourth Climate Change Assessment

The Sierra Nevada region is critical to the environment and economy of California. Its places and peoples provide
essential natural resources including fresh water, clean power, working lands, and famous wilderness. The region
encompasses tremendous geographical, climatological, and ecological diversity that spans majestic mountains to
deep desert basins. The climate consists of cool, wet winters and warm, dry summers with large differences due to
latitude (e.g., the southern Sierra is snowier than northern Sierra) and topography (e.g., the Westside is wetter than
the Eastside). Variability is another notable feature of the climate with the region experiencing some of the largest
year-to-year climatic fluctuations in the United States. Herein we summarize our assessment of climate-change
vulnerabilities and adaptation actions in the region.