Climate scientists agree that the world’s climate is changing and will affect the environment, economy, and communities in which we live. The Sierra has already experienced changes in temperatures and precipitation patterns indicative of climate change, as confirmed by snow survey (1) and other records. The Sierra Nevada supplies two thirds of California’s developed water supply and climate change will significantly alter current water system operations. Climate change also poses real threat to a variety of native species with restrictive habitats needs.

Preparing for the Future

Climate change modeling indicates we should expect to see additional climate change induced impacts to air temperatures, and the timing, magnitude and nature of precipitation events in the Yuba and Bear watersheds over the coming decades. In fact, some experts believe the Yuba, Bear and Feather basins will experience the most significant impacts first in the Sierra, given their relatively low elevations and mostly granitic geology. Some of the anticipated changes for the Sierra include (2):

• 25% to 40% reduction in Sierra Snowpack by 2050
• Higher snowline elevations (about 1,500 ft higher) by the end of the century
• 7-15 week shorter ski season by 2100
• Increased rain-on-snow events, causing greater extremes in river flows
• Earlier seasonal river runoff
• 10% to 20% decrease in streamflows into Sierra reservoirs
• 10°F increase in annual temperatures by 2100, with more heat waves, "spare the air" days, and wildfire dangers
• Migration upstream of cold water habitats that support trout, salmon, and other aquatic life
• Earlier drying of the landscape, and increased frequency of large Sierra wildfires

These forecasted climate changes will substantially impact river conditions and species life cycles. New climate forces will reshape terrestrial vegetation, wildlife habitats, native biodiversity, and the resiliency of our watersheds.

What We Are Doing Now

SYRCL is actively creating partnerships, gathering information and promoting projects to make our watershed more resilient to forecasted climate change. Our River Monitoring project has added sites and target parameters to fine-tune our detection of stressors to our environment. The new Mountain Meadows Health Assessment project ambitiously seeks to assess and monitor the health of our "natural storage reservoirs" and biodiversity hot-spots so that they may be intelligently restored and protected. Our Restoration through Relicensing campaign involves a scientific and multi-organization effort to restore the best possible river flows for protection and enhancement of native biota.

SYRCL and American Rivers have been working through a Switzer Foundation collaboration grant to implement the first ever climate change study plan in a FERC relicensing proceeding. The Yuba-Bear relicensing is uniquely situated to coordinate with ongoing Sierra climate change research at the university, state and regional level and could serve as a model for the relicensing of other projects. This analysis can:

• Provide information needed to help predict the effects of climate change in the Yuba and Bear basins.
• Help identify potential fixes for the effects of climate change.
• Identify a process and mechanisms for adapting or responding to predicted changes in the future.

Program Goals

• Restored cold water habitat
• Utilize natural system resources to improve and ensure ecosystem resiliency (such as mountain meadows, levee setbacks and restored floodplain habitat)
• More monitoring of watershed conditions to facilitate understanding, management, and prediction
• More water and energy conservation incentives and funding

Planning for change facilitates our ability to adapt and respond, and will allow for solutions that can protect our natural resources, native biodiversity, resource management goals, and local economies, and reduce the potential for future conflicts.

Climate and Biodiversity Links

• Sierra Nevada Alliance
• PowerUp Nevada City
• Sierra Nevada Conservancy
• Union of Concerned Scientists
• Sierra Nevada Ecosystem Project
• Yuba Watershed ArcWeb

¹ Gary Freeman of PG&E reported on April 7, 2008 that company snow survey records show a significant decline in April 1st snow pack between the two periods 1945-1975 and 1976-2006. See "PG&E’s Mountain Hydroelectric System and the Changing Climate," Energy Commission Staff Meeting on Climate Change and Energy in California, 4/7/08.

² SOURCE climate change statistics: Auburn Journal Notes re: Sierra Conservancy Symposium 12/5/07, Sierra Nevada Alliance Climate Toolkit